[2025] SADC 35

Prosecution: R Counsel: MS R ANDERSEN - Solicitor: DIRECTOR OF PUBLIC PROSECUTIONS (SA) Defendant: SHILANE MAY QUIST Counsel: MR J WILSON - Solicitor: SHAW LEGAL & ADVISORY Hearing Date/s: 12/09/2023 to 13/09/2023, 15/09/2023, 18/09/2023 to 20/09/2023, 24/10/2023 to 26/10/2023, 20/12/2023 File No/s: DCCRM-15-1198 B DISTRICT COURT OF SOUTH AUSTRALIA (Criminal) DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment. The onus remains on any person using material in the judgment to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court in which it was generated. R v QUIST Criminal Trial by Judge Alone [2025] SADC 35 Reasons for the Verdict of his Honour Judge Allen 4 April 2025 CRIMINAL LAW - PARTICULAR OFFENCES - PROPERTY OFFENCES - ARSON AND LIKE OFFENCES CRIMINAL LAW - EVIDENCE - MATTERS RELATING TO PROOF - STANDARD OF PROOF - CIRCUMSTANTIAL EVIDENCE - GENERALLY The accused elected for trial by judge alone on one count of arson, contrary to s 85 of the Criminal Law Consolidation Act 1935 (SA). It is alleged that on 23 December 2013, at Parafield Gardens, the accused knowing that she had no lawful authority to do so, intentionally or with reckless indifference, damaged by fire a shopping centre, the property of LJ Hooker Commercial Adelaide Pty Ltd. Verdict: Not Guilty Criminal Law Consolidation Act 1935 (SA) s 85(1), referred to. Shepherd v The Queen (1990) 170 CLR 573; R v Hillier (2007) 228 CLR 618; Edwards v The Queen (1993) 178 CLR 193; R v Baden-Clay (2016) 258 CLR 308, considered. -- 1 of 73 -- -- 2 of 73 -- R v QUIST [2025] SADC 35 [Criminal] Introduction 1 On an amended Information dated 6 July 2015 (amended 2 March 2021), Ms Quist is charged with the following offence: Statement of Offence Arson. (Section 85(1) of the Criminal Law Consolidation Act, 1935). Particulars of Offence Shilane Quist on the 23rd day of December 2013 at Parafield Gardens, knowing that she had no lawful authority to do so, intentionally or with reckless indifference damaged by fire a shopping centre, the property of LJ Hooker Commercial Adelaide Pty Ltd. 2 The accused elected for trial by Judge alone. These are my reasons for finding her not guilty of the offence. Overview 3 The accused is charged with one count of arson. On 23 December 2013, some time prior to 5:15pm, a fire was deliberately lit inside a disabled toilet near one of the entrances to the Parafield Plaza Shopping Centre on Salisbury Highway. 4 The accused’s mother operated the Australia Post shop in the shopping centre. 5 The fire was contained to the disabled toilet due to the quick action of three employees from the Foodland supermarket within the shopping centre, who sprang into action and extinguished the fire prior to the Metropolitan Fire Service (MFS) and police attendance. 6 The accused was badly burned in the fire and was taken from the scene by an ambulance to the Royal Adelaide Hospital (RAH). She spent a number of weeks in hospital recovering from significant injuries. 7 The accused sustained burns to just under 24% of her body, particularly to her arms, hands, feet, face and neck. General directions 8 It is not necessary for a court having conducted a trial by judge alone to set out the standard and obvious directions of which a judge is bound to be aware. However, I remind myself of the following matters. 9 The accused is presumed innocent unless and until the accused guilt has been proved beyond a reasonable doubt. This requirement extends to proof beyond a -- 3 of 73 -- [2025] SADC 35 2 reasonable doubt of every element of an offence. It is not sufficient for the prosecution to show a suspicion of guilt or to demonstrate that the accused is probably guilty. In making findings of fact, I must rely upon the evidence given by the witnesses and contained in the exhibits. Expert witnesses 10 In this case, expert witnesses Sergeant Jason Wynne, Dr Duncan Taylor and Mr Simon Cox were called to give expert opinion evidence. Those opinions must be within their particular areas of expertise and the opinions must be based on their knowledge, training or experience. I am entitled to accept or reject any opinion evidence however before doing so I must consider the person’s qualifications, whether their opinion is based on a fact I accept, whether the opinion is in dispute and whether it fits with any other evidence that I have heard and accepted on that topic. Election not to give evidence 11 Although the accused’s evidence was tendered from the previous trial, the accused elected not to give evidence at this trial. The accused was not bound to give evidence. The accused has the right to decline to give evidence. Because that is her legal right, I must not draw any inference adverse to her or the case the accused puts forward from the exercise of that right. There may be many reasons the accused did not give evidence, and I must not speculate on those reasons. I bear in mind that it is at all times, for the prosecution to prove its case beyond reasonable doubt. Circumstantial evidence 12 In this case the prosecution relies upon circumstantial evidence. A guilty verdict cannot be returned unless the proven facts are such as to be inconsistent with any reasonable hypothesis other than guilt. Guilt must be the only rational inference the proven facts enable me to draw. The ultimate question must be decided having regard to all of the evidence, not in a piecemeal fashion. Elements of the offence 13 The elements the prosecution must prove beyond a reasonable doubt are: 1. The accused damaged property; 2. The property is a building or motor vehicle; 3. The accused caused the damage using fire or explosives; 4. The accused intended to damage property or was recklessly indifferent as to whether his or her conduct would damage property. -- 4 of 73 -- [2025] SADC 35 3 14 It is not in dispute that the fire was deliberately lit by a person. What is in dispute is whether it is proved beyond reasonable doubt that it was the accused who lit the fire. View 15 I have had the benefit of attending the shopping centre and observing the layout and the proximity of the relevant places: the post office, the toilets, and the back car park entrance. I take the view into account when assessing the evidence that was lead before this Court. Background – matters not in dispute 16 There are a number of matters not in dispute which I find proven unless otherwise indicated. These matters were set out in a statement of Agreed Facts, tendered as Exhibit P24 and set out in full as follows: STATEMENT OF AGREED FACTS Fingerprints 1. The following items were submitted at the South Australian Police Fingerprint Bureau for fingerprint examination: a. 14/A58392-14 (2L Coke Zero bottle) b. 14/A58392-17 (2L Pepsi bottle) c. 14/A58392-20 (2L Coke bottle) d. 14/A58392-23 (2L Coke bottle) e. 14/ A58392-26 (2L Pure water bottle) f. 14/A58392-29 (1.25L V8 juice bottle) 2. No fingerprints suitable for comparison were located. Chemical Analysis 3. The following samples were delivered to Forensic Sciences of South Australia for analysis of ignitable liquid residues: a. 14/A58392-6 (remnants of plastic bottle) b. 14/A58392-7 (absorbent cloth) c. 14/A58392-16 (fluid sample from 2L Coke Zero bottle) d. 14/A58392-19 (fluid sample from 2L Pepsi bottle) e. 14/A58392-22 (fluid sample from Coke Bottle) f. 14/A58392-25 (fluid sample from Coke Bottle) -- 5 of 73 -- [2025] SADC 35 4 g. 14/A58392-28 (fluid sample from 2L Pure water bottle) h. 14/A58392-19 (fluid sample from 1.25L V8 juice bottle) i. 14/A58392-49 (jeans) j. 14/A58392-19 (cardigan) k. 14/A58392-19 (singlet) 4. Exhibits 14/A58392-40 (jeans), 14/A58392-43 (cardigan) and 14/A58392-44 (singlet) were each packaged within individual brown paper bags with each contained within metal tins. The air space was sampled from each of the metal tins while the packaged clothing remained within the tin and then examined for the presence of ignitable liquid residues. 5. Each of the liquid samples were pale pink in colour which is the colour of unleaded petrol in Australia. 6. The presence of components of petrol were identified in or on the following exhibits: a. 14/A58392-6 (remnants of plastic bottle) b. 14/A58392-7 (absorbent cloth) c. 14/A58392-16 (fluid sample from 2L Coke Zero bottle) d. 14/A58392-19 (fluid sample from 2L Pepsi bottle) e. 14/A58392-22 (fluid sample from 2L Coke bottle) f. 14/A58392-25 (fluid sample from 2L Coke bottle) g. 14/A58392-28 (fluid sample from 2L Pure water bottle) h. 14/A58392-31 (fluid sample from 1.25L V8 juice bottle) i. 14/A58392-40 (jeans) 7. The presence of certain components of petrol on the cardigan and singlet could not be excluded. 8. It is not possible to determine from chemical analysis whether the components of petrol located on any item of clothing was a result of the transfer of petrol in its liquid form or vapour form. 9. Petrol evaporates overtime and can evaporate at different rates from different textiles or fabrics. 10. Petrol is denser then, and therefore weighs, less than water. One litre (L) of water weighs one kilogram (kg), whereas one litre (L) of petrol weighs between 715 to 780 grams (g). Fire Alarm 11. Records from the South Australian Metropolitan Fire Service: -- 6 of 73 -- [2025] SADC 35 5 a. Record the automated alarm at Parafield Plaza Shopping Centre was activated at 5:21pm; and b. That the first fire crew arrived at 5:31pm. Height and Weight 12. Medical notes from the Royal Adelaide Hospital record Shilane Quist as having a height of 163 cm and a weight of 63 kg on 23 December 2013. Injuries 13. Professor John Greenwood does not have the expertise to determine how the burns suffered by Shilane Quist were caused. CCTV Enquires 14. If he was recalled to give evidence, it is agreed that Detective Brevet Sergeant John Schuurmans’ further evidence would be as follows: a. CCTV from the Australia Post Shop from 23 December 2013 was supplied to him on 6 March 2014 by Bruce Quist, the accused’s brother. b. To his knowledge, there was only one camera located within the Post Office, although he did not check this at the time the footage was provided or after the fire itself. The CCTV footage 17 There was a CCTV camera operating from inside the Australia Post shop.1 Its field of vision incorporated most of the inside of the shop and relatively confined areas of the shopping centre floor beyond the glass door and windows of the shop. It does not capture the toilet area. The CCTV footage shows the accused walking away from the shop and out of vision. The footage then records, about six minutes later, an orange flash outside of the shop. The accused is then recorded coming into view, in a distressed state, proceeding to the front door of the shop. The accused suffered serious burns, caused by being close to the fire in the disabled toilet. The accused was the only person injured. Previous civilian evidence 18 I have regard to agreed previous civilian witness evidence in the previous trial that was tendered in this trial.2 This is a summary only. I have considered the entirety of the evidence. Harpreet Kuar3 19 The witness was a cleaner at the Parafield Plaza at the time of the incident. Ms Kuar was tasked with cleaning the toilets. Ms Kuar did not notice anything out 1 Exhibit P18. 2 Exhibits P7 & P8. 3 Exhibit P8. -- 7 of 73 -- [2025] SADC 35 6 of the ordinary whilst they were cleaning the toilets the night before the incident. The witness stated that there was nothing out of the ordinary on the floor of the disabled toilets the day prior. 20 On the day of the fire, Ms Kuar and her husband opened the precinct at 7:00am and began cleaning the car park. They left the shopping centre between 8:00am and 8:30am. Whilst cleaning the toilets the morning of the incident, the witness did not notice anything out of the ordinary at the complex in the area of the toilets. Alyssa Sobey 21 Ms Sobey was employed at the Australia Post shop at Parafield Plaza shopping Centre in December 2013. At the relevant time the witness was employed on a full-time basis and worked Monday to Saturday. Ms Sobey stated that the nail salon, which was next to the Australian Post shop at the time, was vacant and the Animal Welfare League generally shut at approximately 5:00pm. The witness noted the layout of the back room of Australia Post, which was not visible through the CCTV footage. Ms Sobey finished work at 5:10pm at the time of the alleged offending. The witness left the store and was with the accused and her mother at the front of the Post Office. This was consistent with the footage on file 3 of the CCTV footage. When Ms Sobey departed and headed towards Foodland, nothing was observed out of the ordinary. Julie Magill 22 Ms Magill attended the shopping centre at approximately 5:10pm. The witness entered through the rear entrance near the Animal Welfare League. Ms Magill did not observe anything unusual. Ms Magill remained in Foodland for approximately 8-10 minutes, then observed commotion and heard screaming. The witness viewed smoke upon leaving Foodland and what Ms Magill described as a gassy substance coming out of the disabled toilets. Briony Bunting 23 Ms Bunting attended Foodland at approximately 4:00pm or 5:00pm through the main entrance. The witness did not observe anything unusual. Ms Bunting observed the commotion that occurred as a result of the fire. Ms Bunting described hearing a female voice screaming ‘Someone help my daughter’ and observed a great deal of thick black smoke. The witness described the accused as smouldering with flames on her clothes and hair. Ms Bunting attended the post office and poured a bucket of water over the accused. Joesph Sikora 24 Mr Sikora was a Drakes Foodland employee who assisted in putting out the fire. The witness was at the back of Foodland before being alerted to the fire. Mr Sikora smashed the glass to obtain the key to open the box to a fire extinguisher. Mr Sikora cut himself when the glass was smashed. The witnesses’ blood was found at the scene but was never tested. Mr Sikora noted the power -- 8 of 73 -- [2025] SADC 35 7 point for the hand dryer was on fire and noticed a packet of matches inside the doorframe. The witness estimated that it took approximately five minutes to extinguish the fire. Benjamin Huckstep 25 Mr Huckstep was the second Drakes Foodland employee who assisted in putting out the fire. The witness noticed that the industrial toilet roll was on fire as well as the other toilet roll. Mr Huckstep observed the fire scaling the right-hand side of the room. Benjamin Stephens 26 Mr Stephens was the third Drakes Foodland Employee who assisted in putting out the fire. The witness arrived after the other two Drakes Foodland employees noticed that there was a fire. Dr John Greenwood 27 Dr Greenwood was the Director of the Burns Unit and Consultant at the relevant time. Dr Greenwood provided an account of the injuries suffered by the accused. Glen Shepherd 28 Mr Shepherd was a Detective Sergeant at the relevant time and was tasked to attend the Parafield Shopping Centre. Mr Shepherd gave evidence as to the crime scene and the various offices and MFS employees that attended. Andrew Murphy 29 Brevet Sergeant Murphy had been a crime scene investigator since 2003. Brevet Sergeant Murphy had attended thousands of crime scenes and conducted hundreds of DNA swabs and received training in respect to DNA contamination. Brevet Sergeant Murphy attended Parafield Plaza with Sergeant Wynne. 30 Brevet Sergeant Murphy did not take any notes; however, he confirmed that if an item was handled; that is, in terms of collecting the item or taking a sample from the item, then it would have accordingly been marked with the Brevet Sergeant’s initials. Brevet Sergeant Murphy could not recall what if any assistance he provided to Sergeant Wynne during the investigation. Andrew Chandler 31 Mr Chandler was the first MFS member to attend the scene. The witness stated that the automatic firearm alarm came through to the station at approximately 5:23pm. Mr Chandler indicated that the response was immediate. The witness arrived at the shopping precinct at 5:31pm. -- 9 of 73 -- [2025] SADC 35 8 Commander Jeffrey Ruxton 32 Commander Ruxton is a member of the MFS. Commander Ruxton had been a part of MFS for 37 years at the time of giving evidence. At the time, the witness was ranked Commander Central, South Area. At the relevant time of the incident, Commander Ruxton was Commander Manager in charge of the fire investigation section. Commander Ruxton’s duties and roles included to manage the section of the fire investigations and also be a part of the investigation team. 33 The witness attended the Parafield Plaza Shopping Centre on 23 December 2013 at approximately 7:00pm. Commander Ruxton attended alone and met with Sergeant Wynne at the scene. Commander Ruxton’s role and function at the scene was to assist SAPOL, specifically Sergeant Wynne. Commander Ruxton confirmed that one of the roles he performed was to take photographs as seen in Exhibit P2. 34 On entering the disabled toilet, the witness could smell some sort of petrochemical-type smell. Commander Ruxton observed that the ceiling fan cover had been displaced and was on the floor. The witness was involved in the removal of bottles from the ceiling cavity. The exhaust fan was removed to enable access to the roof space, which was where the bottles were discovered. Bottle removal 35 According to the witness, the bottles were removed with a small step ladder and were removed one-by-one and they were handed to one of the police crime scene investigators. Commander Ruxton believed the bottles were handed to either Brevet Sergeant Murphy or Sergeant Wynne. The witness confirmed that they were the only persons present at the scene. Commander Ruxton advised that precautions were taken to prevent contamination of items in the form of wearing gloves. Commander Ruxton only wore one pair of gloves and did not change these gloves during the investigation. The witness stated that it was easier to take the photographs with the gloves on. The witness wore the same pair of gloves during the removal of bottles from the roof space and handled the bottom section of the bottles. Commander Ruxton was not aware of touching the lids of the bottles. The witness observed Brevet Sergeant Murphy and Sergeant Wynne completing DNA sampling of the lids. Both officers were wearing gloves. Commander Ruxton thought it was unusual that Brevet Sergeant Murphy was using multiple sets of gloves for each of the containers. The witness was not involved in the swabbing or sampling of the bottles. 36 Commander Ruxton stated that the void in the roof space was quite large, there was quite a lot of air space. There was one thermal detector located within the disabled toilet that triggered the automatic alarm. Cross-examination 37 In cross-examination the witness was not able confirm where the ladder came from but believed it was brought to the toilet by an external individual. -- 10 of 73 -- [2025] SADC 35 9 Commander Ruxton gave evidence that it was expected that Mr Chandler (who was first on the scene for MFS) would have verified that the fire was extinguished and would have been aware of interfering with evidence at the same time. If the fire was extinguished, then they were trained not to enter the area. 38 Commander Ruxton could not recall if he touched the top of the bottle lids. The witness was still on the ladder when the bottles were passed down to the investigator. Commander Ruxton was not directed by Sergeant Wynne as to how to handle the bottles. The witness confirmed that the bottles were handed down in a safe manner so they would not spill. 39 The witness was in possession of the camera throughout the entire investigation and did not pass it to Sergeant Wynne. 40 Commander Ruxton initially entered the shopping precinct without gloves, but did not touch any surfaces. The witness put gloves on attending the carpark to collect the camera kit. Evidence at trial 41 There were four witnesses that gave evidence at this trial. They were Sergeant Jason Wynne, Dr Duncan Taylor, Detective John Schuurmans and Mr Simon Cox. The following is a summary of the evidence given by each witness. This is a summary only. I have considered the entirety of the evidence. Sergeant Jason Wynne Background & qualifications in relation to crime scene examination 42 At the time of the incident, Sergeant Wynne was a Brevet Sergeant and attached to the Forensic Response Section.4 Sergeant Wynne is a qualified crime scene investigator. The witness completed two courses. One was called the crime visitation course and the second was the scene investigator course.5 In both courses the witness learnt about crime scene processes including controlling the scene and collecting and recording evidence.6 Sergeant Wynne gave evidence that any fire that involved injury or death was referred to the Forensic Response Section.7 43 The witness has a certificate IV in crime scene investigation and has completed a diploma and an advanced diploma in crime scene investigation.8 Part of this training involved ensuring that crime scenes are preserved and not interfered with.9 Sergeant Wynne has been an officer for 20 years and has previously appeared in this Court to give evidence.10 4 T85.10.24. 5 T85.35.38. 6 T86.1.12. 7 T87.11.13. 8 T87.29.33. 9 T91.7.9. 10 T90.25.28. -- 11 of 73 -- [2025] SADC 35 10 Crime scene practices 44 Sergeant Wynne gave evidence that there are a number of ways to reduce the contamination of a crime scene.11 Crime scene control is the first step. This involved limiting the amount of people that are allowed in and out of a crime scene. Depending on the crime scene itself, it may be appropriate to establish an outer cordon and inner cordon that restricts the flow of people.12 There are also measures in place to reduce contamination, including using protective equipment such as gloves and a mask.13 It is also important to ensure that officers are aware of the items that they are sampling, that they are not handling another item prior and possibly transferring and contaminating items and surfaces. Changing gloves when required is appropriate. If an investigator becomes aware of having touched a certain surface, it is general practice to change gloves.14 45 Gloves are used to avoid the transfer of DNA.15 When taking a swab, it is appropriate practice to not place hands directly on either the swab itself or the item that is the subject of the swab. Thus, gloves are a physical barrier to prevent such contamination.16 If an item is touched, it may transfer DNA inadvertently onto the gloves. The gloves operate as a barrier to prevent DNA contaminating a sample.17 Incident 46 Sergeant Wynne attended the Parafield Plaza Shopping Centre at approximately 6:55pm on the day of the incident.18 The witness was aware that there had been a fire within the premises sometime prior to attendance.19 Sergeant Wynne was aware that the fire was said to have occurred sometime after 5:15pm.20 47 If there is a fire scene that is to be attended by Forensic Response, then there is a memorandum of agreement with MFS that two fire investigators will attend, one from SAPOL and one from the MFS. A joint investigation will commence.21 48 Sergeant Wynne was taken through the photographic exhibits.22 The witness took photographs throughout the investigation. Following the photographs being taken, Sergeant Wynne commenced a physical examination, which included sampling.23 The bottles that were located in the roof space were seized and swabs were taken from the lids. The two blood drops that were also identified in the photobook were swabbed and sampled as well as a number of areas inside the toilet 11 T91.14.28. 12 T91.16.20. 13 T91.21.23. 14 T91.23.28. 15 T91.32.37. 16 T91.32.37. 17 T92.2.6. 18 T92.25.27. 19 T92.28.30. 20 T92.31.33. 21 T93.2.8. 22 T95; Exhibit P2. 23 T102.24.26. -- 12 of 73 -- [2025] SADC 35 11 block where the smell of petrol was present.24 The smell of petrol in the various areas of the room included the drain area, under the exhaust fan and the melted bottle.25 The melted plastic bottle had a fluid inside.26 49 There were two methods of sampling that were employed. One was by swab and the other was by an absorbent cloth.27 There was also a further six plastic bottles located in the roof space above the fan.28 At some point Commander Ruxton removed the bottles from the roof cavity.29 They used a ladder to reach the bottles. Sergeant Wynne instructed Commander Ruxton to remove the bottles in order to complete the sampling process. Sergeant Wynne instructed Commander Ruxton to only handle an area that was not the lid of the bottle.30 The lid was a focus area for sampling to ascertain who tightened the cap on the bottles.31 Commander Ruxton used gloves when removing the bottles.32 The bottles were removed one by one from the roof.33 Once a bottle was removed, it was taken by Commander Ruxton to another area within the shopping precinct and placed on the ground. Then Commander Ruxton would return and obtain the next bottle. Sergeant Wynne documented some details of the bottles. Once they were all retrieved, the investigators proceeded to the swabbing stage of the investigation.34 This area was depicted in photograph 34 of Exhibit P2.35 Contamination 50 As part of Sergeant Wynne’s role in processing the crime scene, a number of exhibits were seized. An ongoing exhibits log was maintained.36 51 At approximately 8:50pm to 9:00pm, the bottles that were collected from the roof cavity were swabbed.37 The swab that was used for DNA testing was a foam Popule swab, that was self-wetting and was prefilled with liquid inside of the tube. If the tube was broken, it then moistens the foam tip. A sample can then be taken from the area that is being targeted and placed into a container for storage and further analysis.38 A swab was taken from each bottle that was collected.39 It was solely the lid area where the swab was taken from.40 24 T102.24.31. 25 T102.35.38. 26 T103. 27 T104.1.4. 28 Exhibit P2. 29 T104.8.11. 30 T104.14.19. 31 T104.21.24. 32 T104.31.33. 33 T104.34.36. 34 T105.1.5. 35 Exhibit P2. 36 T106; Exhibit P6. 37 T107.3.7. 38 T107.13.18. 39 T107.19.21. 40 T107.22.23. -- 13 of 73 -- [2025] SADC 35 12 52 Precautions took place to prevent contamination, including ensuring the officers were wearing both gloves and a mask. It was Brevet Sergeant Murphy that took the swabs, whilst Sergeant Wynne observed the process.41 Sergeant Wynne observed Brevet Sergeant Murphy wearing gloves and a mask. Each swab was contained within a sterile packet, it was opened, and the swab completed. It was then packaged into its tube prior to the next swab being taken.42 Each swab had its own separate packaging. Sergeant Wynne observed Brevet Sergeant Murphy conduct each swab. The bottles were also intended to be examined for fingerprints at a later stage but the purpose of the swab at the scene was merely to assess the lids for DNA.43 53 Prior to the process of swabbing, Sergeant Wynne gave a direction to Brevet Sergeant Murphy for the lids not to come into contact with any other item or surface when they were being removed from the roof cavity.44 Each item was given its own exhibit number. Gloves were also changed between each swab. The witness observed Brevet Sergeant Murphy adopt this practice each time.45 Sergeant Wynne gave evidence that it is general practice to wear two pairs of gloves, an inner and an outer pair. After the exhibits were taken, the outer glove was removed, and a new outer glove was replaced.46 54 Various items that were lodged in the exhibit log are detailed in Exhibit P6. The items that were lodged are as follows: • PP1 was an ‘absorbent cloth’ that was used to sample for petrol at the site; • PP2 was a cotton swab, like an earbud that was used around the drain area; • PPS3 was another ‘absorbent cloth’ which was used in the same location, being the drain; • PP4 was the box of matches as depicted in Exhibit P2; • PP5 was an unburnt match which was on the floor near the exhaust fan cover; • PP6 was the remnants of PET bottle and was located on the floor on the east side of the toilet (this is the bottle where he smelt the scent of petrol); 41 T107.28.38. 42 T108.5.9. 43 T108.23.38. 44 T109.25.27. 45 T110.3.11. 46 T110.12.17. -- 14 of 73 -- [2025] SADC 35 13 • PP7 is another ‘absorbent cloth’ that was used around where the melted bottle was located; • PP12 and PP14 were DNA swabs taken from inside the door handle; • PP14 was the first of the bottles from the roof cavity that was retrieved and swabbed; o PP14.1 is the DNA swab of the bottle; o PP14.2 is the fluid sample that was taken from the liquid contained with the bottle. • PP20 and PP21 was the blood swabs that were not subject to forensic analysis; • PP25 was the skin located on the glass window which again was not subject to forensic analysis; • PP28 were blue jeans of the accused which were preserved; and • PP29 to PP32 were further clothing items of the accused. Process of moving exhibit items 55 Once the exhibits are packaged, they go into what is referred to as the ‘case management phase’ of the investigation. Each item is lodged onto the Police Property Management System.47 Once all the exhibits were lodged in the exhibit log, they are transported to the Forensic Response Section office and placed into the secure exhibit room.48 All exhibits that are collected are sealed and they are signed and dated so that the seal can remain, until it is subject to analysis and broken.49 Further precautions and details 56 When Sergeant Wynne first arrived at the shopping centre, the area had been cordoned off by fire service tape.50 The only officers that were present within the cordoned off area were Sergeant Wynne, Commander Ruxton and Brevet Sergeant Murphy when required to assist.51 There were also other individuals present but they remained outside of the cordoned area.52 An area was established called a ‘working area’ where the officers could change and hold equipment as required.53 47 T118.25.38. 48 T118.9.13. 49 T119.7.13. 50 T119.35.38. 51 T120.4.7. 52 T120.8.11. 53 T121.7.12. -- 15 of 73 -- [2025] SADC 35 14 This area was around areas 12 and 13 as outlined in the floorplan, a short distance from the disabled toilet.54 Qualifications in relation to fire investigations 57 As part of Sergeant Wynne’s initial crime scene investigation training there was a fire cause investigation component.55 There was a theory and practical component, which touched on structural fires, vehicle fires and bushfires.56 The fire investigation component involved attending actual or real fire scenes.57 In 2009 the witness completed a bushfire investigation course.58 This course was run by the Country Fire Service. It included both theory and practical assessments. The theory was on the spread of wildfire and pattern indicators and the practical component involved simulated wildfire bushfires, which Sergeant Wynne would examine and determine the cause or the ignition area.59 In 2011, Sergeant Wynne completed a fire investigation theory assessment. This involved specifics in respect of fire science, fire travel and spread, how to engage with other working parties such as a fire service; personal protective equipment, what equipment to wear at fire scenes, examining a structural fire, what fire patterns to assess and how to make an assessment of a cause and determination of the origin of a fire.60 The practical part of the qualification was completed in 2013. This involved attendance as an observer and assistant at fire scenes. As Sergeant Wynne progressed through the practical component, further roles and responsibilities were conferred and the witness would take the lead from the fire investigator from the MFS.61 The witness also studied both fire patterns and source of ignitions.62 Sergeant Wynne noted that for a fire to burn or be sustained, there should be three factors: heat, oxygen, and a fuel source.63 58 Sergeant Wynne maintained up-to-date knowledge about fire investigations, including cause and origin.64 As of December 2013 the witness had attended approximately 30 fire scenes.65 At the time of giving evidence, the witness had attended approximately 80 fires, which included all types of fires.66 Sergeant Wynne had been the primary investigator for about fifty percent of these fire investigations.67 When the witness was a supervisor, it was common for other 54 Exhibit P1. 55 T131.5.12. 56 T131.17.19. 57 T132.28.30. 58 T133.30.32. 59 T133.34.38. 60 T134.34.38; T135.1.4. 61 T135.22.31. 62 T136.31.36. 63 T137.4.6. 64 T145.5.8. 65 T146.1.3. 66 T146.4.14. 67 T149.11.21. -- 16 of 73 -- [2025] SADC 35 15 investigators to seek advice from the witness in relation to certain aspects of the fire investigation.68 Flash Fire 59 A flash fire will occur when there is an ignitable liquid present that will produce a vapour, that vapour will diffuse in the air. If there is an ignition source introduced, such as a match, then there will be a rapid flame that will spread through that diffused air and vapour mixture.69 Backdraft effect 60 Sergeant Wynne gave evidence that a ‘backdraft’ effect is an explosion event. Specifically, in a compartment or a room which is airtight, in that fire growth will be at the point where there is depleting oxygen in the compartment. As the oxygen is depleting, it will start burning down the fire but there will be highly energised particles still in the compartment. Thus, using the example of a window or a door when opened, there will be a sudden influx of oxygen, creating a backdraft event and an explosive effect.70 Fire cause 61 There are many variables that may affect how quickly and how far a fire can spread.71 When attending a fire investigation, the purpose is to determine what has occurred, if the cause of the fire can be identified and to identify an ignition source.72 In the initial assessment and the examination recording phases, the general practice is to assess if there are any patterns that might indicate an area where the fire might have started.73 The witness noted that damage can be so significant that it is not possible to determine a cause or origin of fire.74 Cause of fire 62 When Sergeant Wynne arrived at the scene, information was provided that there had been a fire in the disabled toilet and that a female had been injured and had been taken from the scene.75 Information was conveyed that employees from Foodland extinguished the fire with fire extinguishers.76 After receiving the initial brief information a forensic plan was implemented. The witness was shown photographs of the backpack (an examination of the backpack located occurred sometime after the initial examination).77 The backpack was damaged which was likely by heat or flame.78 There was blue powder across the floor which was a 68 T149.34.38. 69 T151.9.13. 70 T153.25.35. 71 T157. 72 T158.4.6. 73 T159.25.30. 74 T160.7.9. 75 T161.9.11. 76 T161.18. 77 T165.8.12. 78 T166.30.32. -- 17 of 73 -- [2025] SADC 35 16 substance excreted from the fire extinguisher.79 The toilet door sustained heat damage and there was soot present as well as blistering.80 There were black markings above the doorframe as a consequence of the door being opened.81 The markings on the top of the doorframe were likely caused by heat rather than flame itself.82 63 Photograph 20 of Exhibit P2 depicted a matchbox. The witness was unable to recall if there were any unburnt matches within the matchbox.83 The matchbox was not fully affected by fire.84 Photograph 21 depicted the toilet roll and toilet paper where there was fire damage.85 There was also another match found to the upper left of the drain.86 Photographs 23 and 24 depicted a melted bottle or a plastic bottle in the corner next to the toilet.87 Photographs 30 and 31 depicted a melted red bottle lid in the sink.88 64 The toilet itself had soot staining similar to the door. There was a splash-type stain on the tiled wall.89 This demonstrated that there was something burning near the toilet that was producing smoke and creating sooting. The markings on the wall could indicate that ‘something’s been splashed around’.90 65 Photographs 25 ad 26 depicted a bin against the wall. The bin sustained radiant heat damage, which melted the front of the bin. The toilet rolls sustained damage.91 The fire did not start within the bin.92 When assessing the cistern itself, the witness observed that there appeared to be a V pattern on that cistern caused by the flame below.93 The V pattern indicated that there had been a flame in the area, which had burnt away the paint from that cistern.94 The V shaped pattern started in the bottom right-hand corner and extended to approximately the centre of the top of the cistern.95 66 Photographs 32 and 33 depicted the exhaust fan on the ceiling. The blades on the fan appeared to have been melted.96 The material was likely made from plastic.97 The exhaust fan would have been a ventilation point for the fire and the smoke.98 79 T167.19.22. 80 T167.35.38. 81 T168. 13.17. 82 T169. 83 T170.37.38;171.1. 84 T171.1.7. 85 T171.8.19. 86 Exhibit P2. 87 T173.25.29. 88 T174. 89 T175.9.12. 90 T175.14.22. 91 T175.29.34; Exhibit P11. 92 T177.1.3. 93 T181.22.24. 94 T181.30.33. 95 T182.12.16. 96 T183. 97 T184.1.5. 98 T184.27.31. -- 18 of 73 -- [2025] SADC 35 17 The two bottles in the ceiling that were lying down sustained heat damage.99 Following the removal of the exhaust fan cover, Sergeant Wynne did not make any further observations of the particular area.100 The pattern underneath the exhaust fan cover itself was clean as it was protected by the cover.101The plastic from the exhaust fan could have melted from the bottle, which would then explain a clean mark on the ground next to the toilet.102 Workspace 67 The cordoned off area that was used for the designated workspace is depicted in photograph 11 of Exhibit P2.103 The location of the bottles is seen in Exhibit P4. Sergeant Wynne selected this specific work area as it had been cordoned off and was limiting access. There was also no other evidence that needed to be focused on in the immediate area.104 The swabbing occurred in the same location as where the bottles were initially stored and then transferred into a bag at the equipment area.105 The collection kit and other equipment including gloves and masks were also located in this area.106 68 One of the final processes was to clear the toilet floor to see if there were any other patterns or any other evidence that may be obscured by the debris to clean the toilet.107 Ignition source 69 Sergeant Wynne believed the ignition source for this fire was the matches.108 Specifically, the matches that are in the doorway and the unburnt match that was located near the drain.109 The match is an ignition source that introduced the flame straightaway and there were accelerants present in the bathroom.110 Sergeant Wynne excluded the hand dryer as being a possible ignition source given there was no actual damage sustained.111 The witness excluded the fan as a potential ignition source.112 Sergeant Wynne ruled out the possibility of the light switch in the toilet as being the source of the ignition.113 The items in the roof space were not part of the actual cause determination. The cause was based on the evidence found on the melted bottle, the smell of the plastic, the swabs that were taken for further 99 T184.9.18. 100 T189.4.6. 101 T189.17.20. 102 T190.9.13. 103 T185. 104 T187.18.23. 105 T187.28.30. 106 T187.34.38. 107 T188.10.15. 108 T190.37.38. 109 T191.1.4. 110 T191.6.10. 111 T191.16.19. 112 T191.27.29. 113 T177.22.25. -- 19 of 73 -- [2025] SADC 35 18 analysis and the matches themselves.114 When assessing whether it was a deliberately lit fire, Sergeant Wynne took into account the liquid in the bottles, which were a reddish colour similar to petrol and had the smell of petrol.115 Characteristics of a flash fire 70 A flash fire does not always have an explosive effect or damage produced as a result of the effect. It is a flame that spreads rapidly through the diffused fuel, such as vapours or gas, that is mixed with air, which does not necessarily cause an explosion.116 There are many variables and mixtures that affect a flash fire and how rapidly it develops.117 The witness described a flash fire as a very fast moving flame, which would then disappear quite quickly. Once the flash fire is lit, it will ignite anything that is still able to burn and will continue to burn any items after the initial flash.118 Explosion damage 71 In respect to blast damage, there are two types of explosions, namely detonation and deflagration. In relation to an explosion, heat, shock, noise and pressure is created. Depending on the type of explosion, will depend on the amount of damage that may be sustained. If it is a detonation where there is a crater or a blast, as it is instantaneous and quite a violent reaction, the items that are close by could be severely damaged, ripped apart and shattered. In a deflagration explosion, as the type of explosion is a burning effect, there will still be pressure, heat, and noise but the damage will not be as shattering as a detonation explosion. It will be an over-pressure and is capable of moving items. It will still produce a flame and smoke, but it will have as violent reaction as a detonation. 72 The type of space within which an explosion occurs is a relevant factor. Confinement is a factor on whether items will detonate or just burn. The witness gave an example in relation to a sparkler. If you were to take a number of sparklers off and just put those materials on the ground and set this alight, it will just burn. However, if you were to place those materials into a pipe, confine it within the pipe and then ignite it, as it is confined within that pipe, it will explode and detonate rather than deflagrate.119 Backdraft effect 73 There is an explosive force when a backdraft fire effect occurs.120 This is a deflagration explosion and would be on the lower scale of the explosion scale.121 A backdraft effect occurs when the oxygen level in an airtight room is depleted.122 114 T193.8.12. 115 T193.15.17. 116 T195.1.4. 117 T195. 118 T196. 119 T199.1.7. 120 T199.31.32. 121 T199.35.36. 122 T200.1.4. -- 20 of 73 -- [2025] SADC 35 19 The size of the fire required to deplete enough oxygen depends on a number of variables such as how much heat is being released, the fuel load that is available within the room and then the time of how long the fire has been burning to generate the energised material in the room and then finally the introduction of the oxygen.123 The witness noted that time is also a significant factor in a backdraft fire. The fire has to develop to a point where it is producing enough energetic material in the room to suffocate the room of oxygen.124 The greater the ventilation, the longer the time is required for the fire to advance to the state of smouldering or decay.125 Given the fact that Sergeant Wynne did not observe any real explosive damage in the room as well as there being vapours in the room in the form of petrol, ultimately Sergeant Wynne concluded that it was less likely to be a backdraft effect.126 Accelerant 74 Sergeant Wynne gave evidence regarding the properties of petrol in terms of its flammability. The witness noted that petrol is quite flammable, its flash point is low.127 Sergeant Wynne described it as quite a volatile substance.128 CCTV footage 75 The witness gave evidence that the flash of light that was seen in the CCTV footage could be consistent with a flash fire event.129 The door would have to be opened at some point for the flash of light to be visible on the CCTV footage.130 Hypothesis of fire 76 Sergeant Wynne concluded by stating that, having regard to all relevant factors, the most probable hypothesis of the cause of the fire was that it was a deliberate fire by the ignition of some ignitable fuel, being petrol.131 Cross-examination Petrol smell 77 The witness confirmed that the bottles had a strong smell of petrol. The petrol smell was present inside the toilet block itself and was still present whilst the swabbing process was completed.132 123 T201.6.10. 124 T201.24.26. 125 T201.27.29. 126 T206; T207. 127 T202.16.20. 128 T202.21.23. 129 T202.34.38. 130 T203.6.9. 131 T208. 132 T210.31.33. -- 21 of 73 -- [2025] SADC 35 20 Contamination 78 The swabbing of the bottle tops occurred whilst the bottle tops were still intact on top of the bottles.133 Thus, the bottles were not opened at the scene. The witness did not take a note of any of the bottles leaking petrol when they were stood up or laid down on the floor of the shopping centre.134 79 Sergeant Wynne described the contents of the crime scene manual that sets out procedures that should be adhered to by those working at a crime scene.135 Sergeant Wynne was aware of the ever present risk of contamination given extensive past experience.136 The witness was aware of the high obligation of documenting accurately the work conducted at a crime scene.137 Sergeant Wynne double gloved when handling potential exhibits.138 However, no notes of how many gloves were worn or changed during the investigation was recorded.139 Sergeant Wynne’s general practice was to create a rubbish bag to place used gloves in. There was a rubbish bag in the area of the equipment.140 The witness could not recall how many gloves were worn.141 Once a division of labour was established, a record was completed from the start time to the end time. If there was something that was of concern, then it would be documented accordingly.142 80 Sergeant Wynne confirmed that Commander Ruxton and Brevet Sergeant Murphy were working together as part of the investigation at the scene.143 Brevet Sergeant Murphy only performed the swabbing. The actual fire examination and the other sampling was conducted by Commander Ruxton.144 Sergeant Wynne noted that they were not ‘in lockstep’ with each other throughout the entirety of the investigation at the scene. Sergeant Wynne accepted that a potential source of contamination can arise from the way an exhibit was handled within the crime scene.145 Sergeant Wynne’s notes reflected that the sampling occurred, but the notes did reflect by whom or at what time. The movement of the exhibits collected was reflected in Sergeant Wynne’s exhibit list.146 The witness did not take a note of the order in which any of the six bottles were removed from the ceiling space.147 There was no note as to who swabbed the bottle lids.148 Upon reviewing transcript of previous trials conducted in this matter, Sergeant Wynne accepted that he was in fact involved in sampling of the bottle 133 T211.1.3. 134 T211.16.19. 135 T212.1.4. 136 T212.5.9. 137 T212.10.14. 138 T212.26.28. 139 T212.29.38. 140 T213. 141 T213.32.33. 142 T213.33.36. 143 T214.1.3. 144 T214.9.11. 145 T214.29.32. 146 T215.9.12. 147 T215.27.30. 148 T215.35.38. -- 22 of 73 -- [2025] SADC 35 21 lids.149 In hindsight, the witness accepted that notes as to who removed the bottles would have been appropriate in the circumstances.150 81 Sergeant Wynne understood that the accused would have moved through the shopping centre from the location of the fire in the direction of the post office.151 Notwithstanding this, Sergeant Wynne confirmed that the workstation area was still suitable. Sergeant Wynne did not see potential issues with the floor space being an area to work from for sampling. The witness stated that as long as the lid did not come into contact with the floor, the risk of contamination was minimised.152 Sergeant Wynne did not hold any reservations in relation to the location of the work station near the melted skin that was found as that particular skin was stuck to a window and there was no disturbance to the skin.153 Not every droplet of blood was documented on the floor within the shopping centre besides the two that were located in the corridor close to the work station.154 If the investigation was conducted again, the witness would have adopted the same work station and practices in relation to the swabbing procedure.155 Exhibit D13 – photograph of sampling area 82 The blue case depicted in Exhibit D13 was a collection case.156 The paper bags that are seen in Exhibit D13 are the bags that contained the bottles that were removed from the roof space.157 Each bottle was placed in a separate bag. The bottles were placed straight into the bag. The paper bags were stored in the large black case seen in Exhibit D13.158 The phials that contained the swabs, were sitting on the floor in a plastic container. The container was on the tiled floor.159 The purpose of the container was to protect the swab, so once the swab was taken, it was placed in the container and sealed to protect the swab. Therefore, there were no concerns regarding the container being in contact with the floor.160 The witness did not record any notes in relation to where the lids for each of the phials that contained the swabs were placed once they were removed.161 83 Sergeant Wynne did not have any information as to the direction that any members of the ambulance service might have travelled in within the shopping 149 T218. 150 T219.27.30. 151 T220.6.10. 152 T221.23.28. 153 T222.27.28. 154 T223.1.8. 155 T227.7.9. 156 T227. 157 T228.5.7. 158 T228.21.26. 159 T229.32.34. 160 T230.8.10. 161 T231.3.6. -- 23 of 73 -- [2025] SADC 35 22 centre either when they arrived or when they left.162 The witness did not know if any medical treatment was provided to the accused at the scene.163 Clothing 84 Whilst Sergeant Wynne was at the scene, other police officers arrived and provided clothing that was said to have been worn by the accused. It was Detective Webber that delivered the clothing in a number of separate brown paper bags.164 The following items were delivered: one brown paper bag containing blue jeans, one brown paper bag containing a black bra, one brown paper bag containing black undies, one brown paper bag containing a pink cardigan, one brown paper bag containing a red singlet.165 These items were received in the car park of the shopping centre.166 Sergeant Wynne did not record notes of where the clothing was received.167 The clothing was then put into a fire tin. The purpose of the fire tin was to enable tests to be completed at a later time in respect of whether there were any vapours on the clothing.168 Sergeant Wynne does not have any notes of when this occurred.169 The items were placed straight into the tin and then sealed. The witness touched the outside of the brown paper bag when doing this. The witness confirmed that this did not take place in the toilet to reduce the risk of contamination.170 Sergeant Wynne wore two pairs of gloves during the process of placing the brown paper bags in the tin.171 Commander Ruxton 85 Sergeant Wynne was not ‘in lockstep’ with Commander Ruxton during the investigation. They would consult each other on matters but they were not physically with each other for the whole investigation at the scene.172 The photographs were taken by both Sergeant Wynne and Commander Ruxton and the same camera was used.173 The camera was being handed back and forth between each other.174 No notes were recorded of who took which photo.175 Sergeant Wynne accepted that the camera was a vector for potential DNA contamination.176 162 T232.19.22. 163 T232.24.25. 164 T242.1.9. 165 T242.19.30. 166 T242.32.34. 167 T243.1.4. 168 T243.8.11. 169 T243.16.17. 170 T244. 171 T245.13.20. 172 T256. 173 T256.33.38. 174 T257.3.6. 175 T257.12.15. 176 T258.26.30. -- 24 of 73 -- [2025] SADC 35 23 Pen 86 Sergeant Wynne utilised one multi coloured pen that was used throughout the investigation.177 The witness accepted that the pen was a potential vector for contamination of DNA.178 Swabbing 87 The swab containers were labelled each time. It was Sergeant Wynne’s general practice to initial the outside label of the swab container.179 The person that seals the bag will be the person who initials it.180 Sergeant Wynne believed it would have been the person doing the swab and who handled the vial that initialled the swab container.181 However, Sergeant Wynne had no notes of this. The lid of the vials was screwed onto the container. Then the lid would be unscrewed to take the sample.182 Sergeant Wynne was involved in this process and assisted Brevet Sergeant Murphy.183 Sergeant Wynne gave evidence that as the reporting officer, ‘I don't want to be the person that opens that swab’. However, the witness may have opened the container to the swabs.184 88 The witness believed that Brevet Sergeant Murphy would complete the swab and sealed it into the container and labelled it.185 In terms of Sergeant Wynne’s memory of the swabbing process, the witness was reliant on what was standard practise.186 Sergeant Wynne confirmed that the match box was not swabbed for DNA.187 Part of the officer’s training was to identify objects or surfaces that might be a possible source of evidence such as DNA and then to take samples from that particular area188 Protective equipment 89 Sergeant Wynne was wearing a face mask, gloves and fire boots.189 The witness did not believe Brevet Sergeant Murphy was wearing over boots at the time.190 Movement of the accused 90 Sergeant Wynne accepted the possibility that there was movement by the accused within the shopping centre after the accused was burnt, albeit, it was not 177 T258. 178 T258.31.34. 179 T261.14.19. 180 T261; T262. 181 T262.21.25. 182 T263.18.26. 183 T264.4.6. 184 T264.19.25. 185 T265.29.35. 186 T266.4.6. 187 T267.7.11. 188 T270.7.11. 189 T266.24.38;267.4. 190 T267.5.6. -- 25 of 73 -- [2025] SADC 35 24 clear on exactly where that was.191 There were particles of dirt or dust that might have come from the fire itself that was across the floor and surfaces within the shopping centre.192 Qualifications 91 Sergeant Wynne does not have any tertiary qualifications in chemistry or science apart from the advanced diploma through the Canberra Institute of Technology.193 The witness completed this qualification in 2015 or 2016, which was two to three years after the alleged offending.194 It was at the end of 2013 that Sergeant Wynne became authorised for the first time to conduct solo fire investigations.195 The witness had conducted one fire investigation prior to this incident which was a house fire where the house was completely destroyed.196 92 The only other matter where the witness had given evidence in court in relation to fire cause investigations was in 2018.197 In relation to the trial in 2018, there was no obvious indication of any accelerant being used. Instead, the cause was more likely due to a fuel load from inside the house.198 Ultimately, Sergeant Wynne only gave evidence in respect of the area of where the fire was rather then how it started.199 93 This is the first case in which the witness had been asked as an expert to proffer an opinion about the mechanism by which a fire might have started.200 Hypothesis in relation to fire 94 The appropriate scientific method, in terms of a fire investigation, is to define a problem, in this case, it is the fire itself, develop a hypothesis, gather information to test that hypothesis and then adjust, confirm or negate that hypothesis.201 When completing a hypothesis, there are a number of different theories that can be tested, one of the hypothesis was that an accelerant was used to start the fire. Another hypothesis could be where did the fire start and how did it start. The observation of the matches contributed to the hypothesis that the fire was started by match.202 Sergeant Wynne gave evidence that a hypothesis could be formed based on observations at the scene coupled with further analysis. This was an ongoing or working hypothesis based on observations.203 As part of the hypothesis developed, the match was either part of the initial ignition or that the 191 T267.23.26. 192 T267.28.30. 193 T372.1.8. 194 T372.13.17. 195 T372.20.23. 196 T372.29.38. 197 T374. 198 T374. 199 T374.27.33. 200 T374.34.38; T375.1. 201 T376.9.15. 202 T377.1.9. 203 T378.11.12. -- 26 of 73 -- [2025] SADC 35 25 match may have been dropped after ignition.204 The witness did not consider the fact that the matchbox was possibly there for another reason other than being the ignition source of the fire.205 Matchbox damage 95 The damage to the matchbox was deceiving in the photographs due to the fire extinguisher powder. The damage was contained to the fan, the toilet rolls dispenser and the bin. Once the room was cleared, the floor was relatively clear of any damage.206 The unburnt match that was found near the exhaust fan cover was in relatively good condition.207 Backdraft effect 96 In terms of the pre-requisites for a backdraft to occur, Sergeant Wynne accepted that the first pre-requisite is a compartment or a room.208 The second pre- requisite for a backdraft is an airtight room where a fire is still burning. There is no ventilation requirement for the fire to start. The backdraft effect requires an airtight room where oxygen is being depleted from the fire.209 It was suggested that a room or a compartment does not have to be airtight in order for there to be a backdraft event. The witness stated that there is a requirement that there be an airtight or near airtight compartment for the backdraft event to occur. Sergeant Wynne explained that upon reviewing the relevant studies and materials on the subject, there will always be natural ventilation. This ventilation could be caused from a door crack or a window crack.210 When Sergeant Wynne gave evidence in respect of ‘air tight’, this does not refer to no air whatsoever.211 The witnesses’ understanding was that any fire, if it consumes the oxygen in a near airtight environment, once there is an influx of oxygen it may create an explosive event.212 The witness accepted that putting aside whether it was a ventilation controlled fire or not, in the lead-up to a backdraft event, the fire will create a hot gas layer.213 This occurs as the fire is searching for its highest point in the room and it will start moving towards the ceiling, thus creating the hot gas layer.214 Ventilation controlled fire 97 Sergeant Wynne did not give evidence as to ventilation controlled fires at the previous trial. However, the witness was able to give evidence on this topic at this trial. Sergeant Wynne stated that if a room was fully involved in the fire, there 204 T386.11.13. 205 T387.7. 206 T385.2.10. 207 T385.14.15. 208 T389.10.13. 209 T389.17.22. 210 T389.35.38; T390.1.4. 211 T390.5.7. 212 T392.26.29. 213 T393.20.21. 214 T393.20.29. -- 27 of 73 -- [2025] SADC 35 26 could be ventilation being controlled by an opening. Sergeant Wynne’s knowledge was still limited on this topic.215 Deflagration and detonation 98 Sergeant Wynne gave evidence in respect of the differences between deflagration and detonation. Deflagration takes place at a velocity lower than the speed of sound. Contrastingly, detonation is faster than the speed of sound. Both are explosive events and will produce light, heat and a shock wave.216 In terms of a deflagrating explosion in a compartment, the pressure increases, until it finds the weakest point, which may be a window, door opening or roof.217 The increasingly hot air and the increasing pressure searches for an exit from the compartment.218 99 In the event that there is a backdraft in the room, Sergeant Wynne accepted that a deflagration explosion would be capable for the door to be blown out.219 Another way in which the backdraft event could occur is if the door was opened, letting oxygen in and then the deflagration event occurred.220 If the door was opened and the oxygen was introduced and mixed, there is no barrier and the deflagration event will consume the room.221 In terms of sound, detonation is a crack that you would expect to hear when you have a detonation.222 The deflagration sound is not an explosion sound. Instead, it would be a movement-type sound of the fire or the actual event occurring through the air.223 100 In terms of the sound of the deflagrating explosion itself, there may be no more than a whoosh venting outside the door once it is opened. However, it depends on the size of the event.224 Sergeant Wynne accepted it was difficult to say with any precision regarding the size of the event in this matter.225 Type of fire 101 In cross-examination Sergeant Wynne opined that the fire was a flash fire. Sergeant Wynne’s knowledge was limited in respect of backdraft fires and could not exclude this ideal as a possibility in this case.226 The witness sought further peer review studies due to a lack of knowledge that was identified at the previous trial.227 Sergeant Wynne was unable to undertake calculations to determine what is known 215 T390.25.33. 216 T395.32.35. 217 T397.9.13. 218 T397.16.19. 219 T398.1. 220 T398.6.10. 221 T398.6.10. 222 T402.7.9. 223 T402.9.13. 224 T404.24.25. 225 T404.28. 226 T406.23.35. 227 T408. -- 28 of 73 -- [2025] SADC 35 27 as a ventilation factor.228 Due to being unable to perform this type of calculation, it was difficult for the Sergeant Wynne to form an opinion regarding whether there was a ventilation controlled fire.229 102 A key determining factor that led the witness to determine that it was a flash fire was the absence of any explosive damage within the compartment.230 The other factors in favour of the fire being a flash fire included: that there was petrol within the room, the potential for the vapours (petrol) to mix with oxygen and there was an ignition source that can cause these vapours to ignite. Factored into this opinion was the observation that the toilet roll had burnt.231 With a flash fire, one of the characteristics is that the fire will ignite other combustible items in the room such as the toilet roll dispenser.232 Sergeant Wynne accepted that the damage within the disabled toilet was generally at a higher level,233 that is, peeling and blistering of the upper level of the room. CCTV footage 103 Sergeant Wynne gave evidence that the footage was not of great assistance. It was very quick and was at an angle that did not provide a line of sight.234 At the last trial the witness was not prepared to give evidence that the flash of light might relate to or what it might or might not be consistent with.235 Sergeant Wynne cautiously expressed that it could be a fire, or it could be something else.236 Smoke explosion 104 Sergeant Wynne’s understanding which was limited, confirmed that a smoke explosion commences very similar to that of the backdraft scenario, but a smoke explosion does not necessarily need an introduction of oxygen. It is the energised materials in the room which ignite and cause an explosion.237 Dr Duncan Taylor Background & qualifications 105 Dr Taylor is employed by the Forensic Science Centre of South Australia (FSCSA) and was employed as the Chief Scientist of Forensic Statistics at the time.238 Dr Taylor worked at the State Forensic Centre since 2005.239 I have regard 228 T408.33.37. 229 T409.14.19. 230 T412.12.14. 231 T412.19.29. 232 T425.1.6. 233 T426.16.20. 234 T416.8.10. 235 T416.4.8. 236 T416.24.27. 237 T412.3.8. 238 T281.8. 239 T281.10.14. -- 29 of 73 -- [2025] SADC 35 28 to Dr Taylor’s curriculum vitae when assessing the relevant qualifications.240 Dr Taylor has two PhD’s, one in molecular biology and the other in statistics.241 106 Both Dr Taylor’s report and the table of results from Ms Windram were tendered as part of this trial. I have regard to both exhibits when assessing the evidence before this Court.242 107 Dr Taylor had given expert evidence in respect of DNA analysis in over a hundred trials in both the Supreme and District Courts of South Australia.243 108 Dr Taylor provided one report in relation to this particular matter. There was also another report that was prepared by other scientists that Dr Taylor had regard to in preparation of their report.244 109 Dr Taylor gave evidence that DNA was a substance present in most cells of the human body. DNA is located within cells. 245 Some sources of DNA such as biological fluids are richer than others. If you have a sample that has a very rich source of DNA, it increases the chances that scientists will be able to generate a DNA profile from that sample. If there is a large sample of a very DNA-rich source, then it would be easier to generate a DNA profile. Contrastingly, when assessing trace DNA samples, the DNA profile may have such low levels of DNA that a DNA profile cannot be generated.246 DNA transfer 110 There are a number of factors that will dictate whether or not DNA is left on an item.247 The factors that will effect this included: how long that item was touched for, how much pressure was applied or whether there was any friction involved in the touching, and the property of the surface of the object. Once DNA has been deposited onto an item, whether or not it persists on that item depends on the conditions that the item was kept within, such as exposure to water, moisture or heat that can break down DNA. Whether or not DNA will be detected will depend on the sampling device used, whether the sample area contained remaining DNA and whether a DNA profile can be generated from that sample. 111 Dr Taylor gave evidence that there is a concept in forensic science known as shedder status. That is, studies have shown that certain people tend to be more prone to shedding their DNA or leaving their DNA on items which they have touched as opposed to other individuals.248 If increased pressure or friction is 240 Exhibit P15. 241 T281.23.29. 242 Exhibit P16; Exhibit P17. 243 T283.12.18. 244 T283.2.5. 245 T283.23.27. 246 T284.13.23. 247 T284.31.33. 248 T286.11.15. -- 30 of 73 -- [2025] SADC 35 29 applied, then more DNA may be deposited onto an object, and in particular if that object has a rough surface.249 Bottle cap DNA transfer 112 A bottle cap contains features that may increase the likelihood of DNA being deposited. A key feature includes the rough surface of the ridges. Likewise, typically when removing or tightening a bottle cap, there is pressure or friction involved. These two aspects can increase the amount of DNA that might be deposited onto a bottle cap. This has a practical effect that there is an increased possibility that a DNA profile may be able to be generated and sampled.250 Dr Taylor noted that moisture and heat will tend to break down DNA.251 Primary transfer 113 Primary transfer or direct transfer is transfer of DNA from a person to an object because they have come into direct contact with that object.252 An example is holding a pen, where there would be DNA left from the direct transfer of touching the pen. Secondary transfer 114 Secondary transfer is when DNA is deposited on an item from an individual, not because they have touched it directly, but due to their DNA being transferred through an intermediatory object. An example of this is if a person shakes a person’s hand outside of the courtroom, some of their DNA may have transferred onto the persons hands. If that person handles, for instance, a pen and if that pen was tested, the pen might detect DNA from both persons involved in the scenario.253 FSCSA 115 Dr Taylor confirmed that there were a number of swabs received by the FSCSA in relation to this matter. When the samples were sent to FSCSA, they are either in a sealed bag or envelope that is sealed until it is opened for analysis.254 A swab is submitted straight to the laboratory technicians.255 116 There are a number of processes that are conducted to generate a DNA profile. The first would be DNA extraction, where DNA is released from any material that is present on the swab. The second would be quantification, which determines how much DNA has been obtained. The third is polymerase chain reaction (PCR) which targets specific areas of interest in forensic profiling. The final stage is called capillary electrophoresis. This is where the areas that have 249 T286.21.27. 250 T286.36.38; T287.1.7. 251 T287.14.17. 252 T288.1.3. 253 T288.13.25. 254 T292.2.5. 255 T292.11.12. -- 31 of 73 -- [2025] SADC 35 30 been amplified are run out on an instrument and appear as bumps on a graph, and that is what is known as a DNA profile. Each of those particular stages have various processes and procedures and controls to ensure that the sample integrity is maintained throughout the process.256 117 During the extraction phase gloves are changed between handling of swabs.257 Dr Taylor then detailed the steps taken to avoid contamination of the contents of the swab.258Dr Taylor confirmed that scientists are trained not to touch the swab head with their gloves. The swab head will be minimally or not be touched at all, and either forceps or scissors are used to remove that swab head from its original holder into the extraction tube.259 If a result was received where there had been some form of contamination, there would be an investigation into how that contamination had occurred but ultimately the contamination would be reported.260 118 When DNA profiles are obtained, the first step is to assess the profiles to ensure their suitability for analysis. The scientists determine a reasonable number of individuals that may have contributed DNA to a sample. An assessment is made as to whether if it is a single source evidence sample, or whether it could be a sample contributed to by multiple people (mixed profile). Once the number of contributors has been ascertained, the profile is analysed in a computerised system which detangles mixed DNA profiles into individual profiles. The reference DNA profiles are the compared to the evidence DNA profile using a computerised system to yield a statistical weighting.261 DNA sampling – DNA samples extracted from two swabs 119 The first item from which a DNA profile could be extracted was a swab of the 2 litre Pepsi bottle lid.262 The second item from which a DNA profile could be extracted was a swab of a 2 litre water bottle lid.263 The DNA profile description concludes that there is a Mixed DNA profile of three contributors for the 2 litre Pepsi bottle and two contributors for the 2 litre water bottle.264 There was insufficient DNA for profiling in relation to the other bottle lids that were swabbed. Hypothesis 120 When a DNA profile is analysed through the STRmix computerised system, two possibilities are considered. One is that the person being compared is a contributor of DNA to that sample and the other is that the person that is being compared is not a contributor of DNA in that sample and any similarities between the reference and the evidence sample would therefore have to be by chance. 256 T292.20.33. 257 T293.19.21. 258 T294.19.30. 259 T294.36.38. 260 T297.23.25. 261 T299.12.30. 262 T301.10.12 263 T302.10.12. 264 T302.18.19. -- 32 of 73 -- [2025] SADC 35 31 When considering the two competing hypotheses, a calculation is expressed in the form of a likelihood ratio, which is the statistical weighting in favour of either hypothesis. 121 In relation to the 2 litre Pepsi bottle swab, FSCSA received a mixed DNA profile that has originated from three contributors. Consideration is given to two different hypotheses when comparing the reference sample to the evidentiary sample. Firstly, the three contributors of DNA are the accused and the two other unknown individuals (hypothesis 1). The alternate hypothesis considered was whether the DNA profile originated from three unknown people and the accused is not one of the contributors of DNA (hypothesis 2). In this case a likelihood ratio of 19 billion was in favour of the first hypothesis.265 This means that there is extremely strong support for the first hypothesis, that is, the accused is one of the three contributors to the DNA profile.266 In relation to the 2 litre Pepsi bottle, further analysis was conducted and statistical weighting of 4.8 billion was found in favour of, again, hypothesis 1, being that the accused’s DNA profile was a contributor to the mixed DNA sample.267 122 The STRmix analysis of these profiles provides further information regarding the DNA profiles during the analysis. For this particular sample (2 litre Pepsi Bottle), the three contributors are broken down into percentages of 82%, 13% and 6% as the three contributors to the mixed DNA profile.268 The accused’s reference profile most closely aligned with 82%.269 123 The next item that was analysed was a swab of a 2 litre water bottle. The DNA profile description was a mixed DNA profile of two contributors.270 The two hypotheses or interpretations detailed in Ms Windram's report illustrated a statistical weighting of 19 billion in favour of hypotheses 1.271 Upon re-analysis, the statistical weighting was 1.3 billion again in favour of hypothesis 1.272 For this particular profile, there were two contributors broken into percentages of 94% and 6%.273 The DNA profile of the accused most closely align with the 94% contributor in respect to this DNA profile.274 124 Dr Taylor explained that the reason for the re-analysis and different results was as a result of new and improved version of STRmix being available by 2019, after the first trial and before this trial. 265 T303.7.34. 266 T304.4.7. 267 T305.28.30. 268 T306.24.29. 269 T306.32.33. 270 T308.4.5. 271 T308.9.12. 272 T308.20.22. 273 T308.31.32. 274 T308.35. -- 33 of 73 -- [2025] SADC 35 32 125 Dr Taylor noted that it is not always the case that if an individual does come into contact with an item that that DNA profile will be revealed as a contributor. Cross-examination 126 FSCSA assume that the exhibits that are received have been handled appropriately and correctly by police.275 If an individual is wearing gloves then that may minimise the chance of contamination.276 Dr Taylor accepted that the presence of DNA does not provide any information as to how DNA was deposited on an item.277 Aerosol transfer 127 Aerosol transfer occurs when DNA has been deposited on an item through no direct contact. Dr Taylor gave the example that all persons tend to shed skin cells and aspirate small saliva droplets and these can settle on items and on surfaces in quantities that may be detected.278 Dr Taylor accepted that it is possible that, at any given time, there could be small amounts of cells that contain DNA floating in the air.279 Dr Taylor noted that a human sheds millions of cells per day.280 Forensic procedures and contamination 128 Dr Taylor gave evidence regarding quality assurance testing results. Dr Taylor noted that DNA from persons who did not work at FSCSA were found on various locations within the building.281 The laboratory technicians taking the samples would wear masks, hair nets and booties.282 There would be procedures employed regarding the use of any equipment that was in proximity to items that are being examined.283 Dr Taylor accepted that if an individual either gloved or ungloved then made contact with another individuals DNA and then uses their pen, that person may have deposited that person’s DNA onto their pen.284 It is possible to have DNA present on gloves, then transfer that DNA to a pen that is being used.285 The witness confirmed that any tool that is used in the process of an examination is a potential vector for contamination, which includes a camera.286 129 It was put to the witness that if it was assumed that there was clothing that was being worn by the accused, when the accused suffered significant burns, it may be expected that as a result of that event those clothes or at least some of the clothes the accused was wearing at that time would be a rich source of DNA. Dr Taylor was not aware of any particular study that would address this topic, but 275 T313.13.15. 276 T314.1.2. 277 T315.30.32. 278 T317.5.11. 279 T317.12.14. 280 T317.25.27. 281 T321.19.22. 282 T322.1.19. 283 T323.21.28. 284 T324.7.11. 285 T324.22.23. 286 T324.32.33. -- 34 of 73 -- [2025] SADC 35 33 from a commonsense view: ‘if you are badly burnt and your skin is weeping as it does when you are badly burnt, then you might transfer quite a lot of DNA through that biological fluid to something you were wearing’. Therefore, it could be a rich source of DNA.287 Dr Taylor gave evidence that ideally there should be minimal movements of exhibits at a crime scene. For example, an item of clothing that was removed from the scene and subsequently returned is suboptimal.288 130 Dr Taylor accepted that it was also suboptimal to place the exhibits (bottles) and conduct sampling on the floor.289 It would help to minimise any potential contamination risk if there was a clean barrier between the item and wherever it was placed.290 If the swabs are to be taken at the scene, then it should occur some distance from the area where it was suggested that the suspect or the victim has been burned or might have walked through after being burnt.291 The best place to sample the bottles in question would be a location that was completely clean and separate to the location where the bottles were retrieved from.292 131 Dr Taylor accepted that it was possible that there could be skin cells or other biological material of the accused that could be deposited on the floor of the shopping centre.293 It was possible that in the course of police moving in the area where the swabbing occurred, DNA from the accused could be re-circulated through the air.294 Dr Taylor accepted it was possible some DNA might make contact with or land on a particular exhibit or more than one exhibit in that general area.295In terms of the state of the floor which bottles were placed, Dr Taylor accepted that that was far from ideal in terms of a surface for the bottles to be placed, if DNA swabbing was to be undertaken.296 132 The witness accepted that if a person wore the same pair of gloves the whole time and handled the bottles, it would be possible for DNA to be deposited on the lid of a bottle if the person came into contact with the lid of that bottle with their gloves.297 The witness accepted that if a bottle was taken from the ceiling space and passed to one or more other persons who received the bottle, that could also lead to potential contamination.298 Dr Taylor stated that the force with which a particular lid might have been touched, the duration of time that the lid might have been touched, what part of the gloves or gloves made contact with the lid, could then 287 T326.1.4. 288 T326.25.38; T327.1.9. 289 T327. 290 T328.6.8. 291 T329.1. 292 T329.2.6. 293 T329. 294 T330.9.11. 295 T330.16.18. 296 T331.12.16. 297 T337.33.38. 298 T338.1.7. -- 35 of 73 -- [2025] SADC 35 34 result in the accused’s DNA being a contributor to the mixed DNA profile of the bottle lids.299 Re-examination 133 Dr Taylor stated that with aerosol transfer you would probably expect to see multiple DNA across items. Dr Taylor also gave evidence about a study, the effect of which was to suggest that the less time you spend in an area, the less opportunity there is for DNA shedding. The witness identified that the unknown in this case was that the subject had suffered burns and what impact this might have on shedding. Detective Brevet Sergeant John Schuurmans Background 134 Detective Brevet Sergeant John Schuurmans has been a police officer for 32 years.300 Detective Schuurmans was stationed at the Barossa Criminal Investigation Branch. At the time of the offending, Detective Schuurmans was stationed at Elizabeth Criminal Investigation Branch.301 Investigation 135 Detective Schuurmans attended the Parafield Plaza Shopping Centre and arrived just after 5:30pm.302 On arrival Detective Schuurmans spoke with Detective Sergeant Matthews.303 The witness then attended the RAH to make inquiries of the accused.304 Detective Schuurmans was with Detective Webber at the time. Initially the witness spoke with one of the staff members at the RAH that was dealing with the accused and then spoke very briefly to the accused and collected her clothing, along with some personal items.305 The clothing that was collected consisted of a red top, a pink cardigan, a black bra, black underpants, blue jeans, one white thong and an Apple iPhone in a pink cover.306 All of the items were seized . The clothing was provided to Sergeant Wynne and the mobile phone and thong were lodged with the Elizabeth property section.307 Detective Schuurmans seized the CCTV footage as part of the investigation. Cross-examination 136 Detective Schuurmans liaised with a landlord or a real estate agent, Mr Pancione.308 In the course of liaising with Mr Pancione, Detective Schuurmans 299 T338.25.38.; T339.14. 300 T348.7.9. 301 T348.13.14. 302 T348.33.38. 303 T349.11.12. 304 T349.15.19. 305 T349.28.31. 306 T349.34.36. 307 T350.2.5. 308 T358.20.23. -- 36 of 73 -- [2025] SADC 35 35 was provided with a receipt from an electrician dated 8 January 2014.309 The receipt related to some of the reparation work that was undertaken in the disabled toilet.310 137 Detective Schuurmans gave evidence about the various police officers that were present as detailed in the operation log.311 Detective Sergeant Matthews directed Detective Schuurmans to seize the clothing at the hospital from the accused.312 The evidentiary purpose was to assess if ignitable residue testing might be able to be conducted on the items of clothing.313 Detective Schuurmans confirmed that at this stage of the investigation, it was not the purpose of their attendance to test the clothing for DNA.314 138 It was put to the witness that the bags containing the accused’s clothing were not placed in sperate bags but all in the same one bag. The witness was then taken to the evidence from the previous trial on this topic. Detective Schuurmans agreed that it was one bag from hospital staff where the clothing was placed.315 Detective Schuurmans was handed the bag in the burns ward.316 There was only one thong in the bag that was provided, and a second thong was never located as part of the investigation, until subsequently at the hospital.317 139 Detective Schuurmans reached into the bag that contained the clothes, pulled out an item of clothing and placed it into a brown paper bag. Detective Schuurmans was wearing gloves at the time. The witness then folded the bag over and sealed it.318 Detective Schuurmans changed gloves for every item of clothing but did not make a note.319 This was in line with standard practice, therefore, believed this was what occurred.320 There was no mention of a thong on the property receipt.321 140 Detective Schuurmans confirmed that after the clothing was received, the brown paper bags were taken back to the scene.322 The witness stated that Detective Webber then provided the clothes to Sergeant Wynne.323 Detective Schuurmans attended with Detective Webber when the clothes were provided to Sergeant Wynne.324 No screwdriver or similar tool was ever located as 309 T358.24.25. 310 T358.29.33; Exhibit D20. 311 T360. 312 T361.3.10. 313 T361.15.17. 314 T361.18.20. 315 T362.8.29. 316 T362.31. 317 T363.4.11. 318 T363.36.38; T364.1.6. 319 T364.10.13. 320 T364.24.25. 321 Exhibit D21. 322 T366.4.7. 323 T366.11.14. 324 T366.15.26. -- 37 of 73 -- [2025] SADC 35 36 part of the investigation.325 Detective Schuurmans did not have a note of a screwdriver being located in the accused’s backpack.326 Simon Cox (defence expert) Background & qualifications 141 I have regard to Mr Cox’s qualifications including the witness’s curriculum vitae.327 Mr Cox has a Bachelor of Applied Science in Secondary Metallurgy and obtained this qualification in 1976. Mr Cox completed a graduate diploma in metallurgy and materials in 1977. Mr Cox was then admitted as a member of the Institution of Metallurgists in 1981 and was a Chartered Engineer. Mr Cox then completed a Master of Arts degree in fire investigation in 2008 and was nearing the completion of a Doctor of Public Safety degree.328 142 Mr Cox was awarded an honorary fellowship of the Institute of Fire Engineers in 1985.329 For approximately 10 years, Mr Cox was an active firefighter serving in a brigade and then as a Deputy Group Officer for the Model Range Group, which incorporated a number of brigades. Mr Cox served as a planning Officer within an incident management team where catastrophic conditions are predicted, or fires are running on those days.330 143 Mr Cox had completed over 3,000 investigations throughout Australia, New Zealand and Asia .331 Approximately 60% of Mr Cox’s work related to fires and 30% or more to material failures and then 10% in respect of explosions.332 Mr Cox had appeared as an expert witness in criminal, coronial and civil courts on over 100 occasions.333 Mr Cox had appeared within all jurisdictions throughout Australia including South Australia, Western Australia, Northern Territory, ACT, New South Wales, Victoria, Tasmania, as well as New Zealand, Singapore and Malaysia.334 The witness had been involved in investigating fires on numerous occasions.335 144 Since 2016, Mr Cox has held a position as an adjunct lecturer at the Charles Sturt University. Mr Cox had taught the fundamentals of fire investigation which related to investigating fires and fire setting behaviour. This related to what motivates individuals to deliberately set fires.336 325 T366.33.38. 326 T367.1.5. 327 Exhibit D26. 328 T458.23.28. 329 T459.1.6. 330 T459.17.25. 331 T460.8. 332 T460.8.9. 333 T460.37. 334 T461.2.7. 335 T462-465. 336 T465.22.29. -- 38 of 73 -- [2025] SADC 35 37 Compartment fire 145 A compartment fire is a fire within an enclosure or compartment such as a building, beneath the deck of a boat, within a motor vehicle or within a shed. A compartment fire typically will develop through a number of predictable and reproducible stages. During the initial stage, when there is abundant oxygen available and a flame is used or a flame ignites and sustains itself within a compartment, a fire will develop as a plume, and will develop at a rate that is controlled by the fuel that is being burnt. The rate of development of the fire is controlled thereafter by how much air can enter the building to sustain the combustion.337 Mr Cox confirmed that the disabled toilet, in this matter, would be considered a compartment and the fire under investigation would be considered a compartment fire.338 146 A fire in a compartment can be either ventilation controlled, or fuel controlled. It was appropriate to complete a calculation to determine which one of those it was. If the vents are large enough, for example if there is an open door or an open window, then the fire is not ventilation controlled, it is fuel controlled.339 Ventilation controlled fire 147 A ventilation controlled fire is a fire in which the growth of the fire is controlled by how much air can enter the compartment.340 Clean burn 148 A clean burn is a fire pattern that was described by literature as a sustained flame against a wall or some other barrier and either disallows the deposition of soot and other pyrolysis products on the wall or consumes products that were deposited on the wall prior to the flame making contact with the wall. The clean burn, in this case, indicated that there had been a prolonged flame burning in this particular area.341 Normally in circumstances of a clean burn there will be no soot on the wall, as it has been consumed by the fire plume.342 Types of explosions 149 Mr Cox gave evidence in relation to three key types of explosions. 150 The first was a mechanical explosion. A mechanical explosion is one that does not involve any chemical reaction. It is similar to a hot water service valve failing and the pressure inside the cylinder increasing to such an extent that the cylinder ruptures. 337 T466.22.38. 338 T467.29. 339 T470.5.12. 340 T468.35.37. 341 T470.14.25. 342 T479.1.3. -- 39 of 73 -- [2025] SADC 35 38 151 The second was a deflagrating explosion. A deflagrating explosion requires explosible material to be airborne and that explosible material can be either a dust, a vapour or a gas which must be airborne and be within a concentration that is within the flammable range, that is, its concentration within air has to be greater than the lower flammable limit or lower explosible limit and less than the upper flammable or upper explosible limit within the flammable range. 152 The third is a detonating explosion. A detonating explosion does not require containment. It is also different to a deflagrating explosion, which requires a flame or a spark to ignite the combustion process, whereas a detonating explosion requires a shock wave.343 153 The transition from deflagrating explosion to a detonating explosion is an extreme rarity.344 In terms of the deflagrating explosion, an important aspect is that it occurs in a container or is in a confined space.345 Explosive limit 154 The flammable or explosible limits can be used interchangeably and they relate to gas, dust, and vapours principally. The lower flammable limit is the concentration above which ignition will occur and the upper flammable limit is the concentration below which ignition shall occur. Thus, if the concentration of the reactant is above the upper limit, it is said to be too rich. If it is below the lower limit, it is said to be too lean. If it is between, it is said to be within the flammable range. Mr Cox gave an example in relation to a motor vehicle. If gasoline was injected into the cylinder and too much gasoline was injected, it will be too rich for the spark plug to ignite. Conversely, if too little gasoline was injected, there would not be enough present for the spark plug to ignite.346 155 The terms 'flammable limit' and 'explosive limit' are interchangeable. Flammable is used for gas explosions or gas combustion.347 Flammable limits 156 There is an ideal known as a stoichiometric measure. This is the appropriate mixture at which all fuel is consumed. This will be somewhere within the flammable range.348 V pattern 157 Mr Cox gave evidence that a fire develops as a plume, and it travels upwards towards the ceiling and the hot gasses begin to accumulate beneath the ceiling. If that plume is in proximity to a wall or an item of furniture then the radiant heat from the burning fuel, the burning plume, can form a pattern on the wall or the 343 T471. 344 T474.13. 345 T474.20. 346 T475.24.38. 347 T476.4.7. 348 T477.18.25. -- 40 of 73 -- [2025] SADC 35 39 item of furniture and that is known as a reflection of the plume. Fire investigators, interpret the V Pattern as an indicator of where the primary fire plume was located.349 Mr Cox confirmed that the V pattern that Sergeant Wynne referred to suggested that there was an item below the cistern that was burning sufficiently to cause the paint to be consumed.350 Backdraft effect 158 Mr Cox gave evidence in relation to the backdraft effect. The pre-requisite for a backdraft is a ventilation controlled fire in a compartment. 159 Mr Cox described what happens during the second stage of fire development, that is, items that have been consumed (the fuel) is not burnt to completion. Instead, items are consumed and transformed into carbon dioxide gas. The fire then reaches an inefficient stage where the descending hot gas layer is full of partially burnt products. Then if someone were to open a door and introduce air into the room, or a window breaks and air enters the room, the oxygen comes into contact with a prolonged or continuing flame that will ignite. The ignition of the unburnt gasses as they enter more air will also become flammable and a fireball effect will occur. 160 Therefore, the pre-requisites are a compartment, a ventilation controlled fire that becomes effectively starved of oxygen, the introduction of air and a sustained area of flaming. Mr Cox confirmed that it does not necessarily need to be flame but a sustained ignition source.351 Fire investigations 161 Mr Cox gave evidence and examples regarding the assessment process when investigating a fire. For building fires, it is customary to walk around the outside of the building upon arrival, as Sergeant Wynne described. In the process of doing so, it is appropriate to assess any windows that have failed and to assess if there is any evidence of a forced entry. It is then necessary to evaluate the fracture surface to assess if it has been broken inwards or outwards. Thereafter, it is appropriate to formulate a hypothesis that there has been an explosion within the building that has happened before the fire, and it has propelled those items of glass out. If the glass is sooted, it is appropriate to conclude that the explosion has occurred during the course of the fire.352 162 Mr Cox gave evidence regarding the relevance of soot in determining whether a backdraft event occurred. Mr Cox stated that the presence of soot represents that the fire inside has gone through the second stage, the inefficient combustion stage, during which all of that soot has deposited, for instance, onto windows. This is the time during which there can be a backdraft event. If oxygen is introduced by opening a door or fracturing a window and then the pressure will 349 T478.1.9. 350 T478.24.30. 351 T479; T480. 352 T340; T341. -- 41 of 73 -- [2025] SADC 35 40 propel the broken glass fragments with the soot on them beyond, outwards from the building. It is then necessary to study how far outwards the objects are propelled and make an assessment on the pressure that has been built up inside the building.353 163 In relation to this particular matter, the presence of the dark black soot within the disabled toilet was indicative of there being a ventilation controlled fire.354 Mr Cox disagreed with the following evidence provided by Sergeant Wynne: 'Soot is going to be created regardless of restriction'. Mr Cox stated that soot is an indication of inefficient combustion.355 Mr Cox further confirmed that black smoke is present if petrol is burnt ineffectively, which was contrary to Sergeant Wynne’s evidence.356 Smoke explosion 164 Mr Cox gave evidence that smoke explosion and backdraft have incorrectly been used interchangeably. The principal difference between a backdraft and a smoke explosion is that a backdraft requires a door to open or a window to introduce air to the mixture, as opposed to a smoke explosion, where that is not required.357 Flash fire 165 Mr Cox gave evidence that a flash fire is where there is a pool of flammable liquid such as gasoline and the vapours that are formed above that pool will tend to flow across the surface of the ground and if they reach an ignition source, then the vapours will ignite.358 Mr Cox confirmed a flash fire can result in an explosion.359 Methodology of investigation in relation to the matter 166 Mr Cox gave evidence that the methodology that should be or ought to be adopted when undertaking any investigation of a fire was one that has been recommended by the document NFPA 921, which was discussed during the course of the evidence. The witness noted that the methodology that was recommend is the scientific method.360 The method directs, first of all, to establish the origin of the fire and then establish the cause. 167 In respect of the origin of the fire, it is first appropriate to collect evidence and interpret data to enable the formulation of a hypothesis. When investigating a structural file, it is necessary to assess the range of fire patterns. It is also appropriate to assess witness accounts, the electrical system within a building, and 353 T481.35.38; T482.1.9. 354 T482.21.28. 355 T483. 356 T483.1.12. 357 T485.9.25. 358 T488.6.17. 359 T489.25.31. 360 T490.27.33. -- 42 of 73 -- [2025] SADC 35 41 the behaviour of a structure should it subsequently collapse. A hypothesis would then be formulated and tested. If the hypothesis fails, then it is necessary to collect more data and repeat the process in an iterative way. 168 Having established the origin of the fire, it is appropriate to adopt the same process for collecting data, making observations, and then formulating the hypothesis as to the cause and, again, if the hypothesis fails, it is necessary to collect more data. 169 As an extension to the methodology relating to the origin, when it comes to the cause, it is necessary to test the hypothesis against the broader scientific knowledge which may include completing calculations, experiments and assessing literature.361 170 Mr Cox stated that it was entirely appropriate to assess the broader scientific knowledge to better understand a topic. Thus, Sergeant Wynne conducting further research on the topic of backdraft events after the previous trial was appropriate.362 Mr Cox noted that Sergeant Wynne only referred to two texts that provide a rudimentary or superficial explanation of backdraft events.363 Ventilation factor 171 Mr Cox was able to perform a ventilation factor calculation. Mr Cox performed such calculations regularly and noted that the ventilation factor was fundamental to the equations that then follow.364 To calculate a ventilation factor for a compartment, it is necessary to measure the dimensions of each vent or potential vent. When considering the compartment, it is appropriate to assess how air can enter that compartment. In this case Mr Cox estimated that the gap on either side of the door and above and below the door and the dimensions of the fan as being the only sources of ventilation into the room (compartment) and then utilised this information to calculate the ventilation factor. 172 As part of the previous trial, Mr Cox attended the shopping centre and assessed the size of the gaps as they exist now and amended the calculation to reflect the actual measurements. This made a slight difference to the calculations but not to the overall conclusion.365 Having regard to the materials considered, including photographs, damage and sooting, Mr Cox formed a view that the fire was a ventilation controlled fire. To test this hypothesis, Mr Cox completed additional calculations to either fortify or potentially disprove this hypothesis.366 361 T491-492. 362 T495.13.21. 363 T496.24.29. 364 T497.34.38; T498.1.2. 365 T498.6.21; T499.1.6. 366 T500.1.10. -- 43 of 73 -- [2025] SADC 35 42 Ultimate hypothesis 173 Mr Cox opined that the accused suffered injuries as a result of either a backdraft or a smoke explosion. Had the accused opened the door, then a backdraft effect could have occurred. Had the accused not opened the door, but the accused had approached the door, and a smoke explosion occurred, again the accused could have suffered the injuries as a result a smoke explosion. Consequently, the injuries that the accused sustained, the circumstances under which those injuries were sustained, were ultimately consistent with either a backdraft or a smoke explosion depending on whether the accused did or did not open the door to the bathroom.367 174 Mr Cox gave evidence that if the fire was a flash fire, then there would not be an explosion unless the vapours were contained. For example, if a person opened the door and applied a match to a pool of gasoline, the flame would spread across the trail of gasoline that would create a substantial flame on the floor. Due to gasoline being denser than air, the vapour contained is at floor level. Therefore, there is low level damage to the room associated with that spread. 175 Mr Cox confirmed that it was necessary to differentiate between what occurred at the low level and higher level of the disabled toilet. As a result, Mr Cox concluded that a flash fire was unlikely as hot gasses had escaped. 368 Mr Cox had regard to the accused’s evidence where the accused had ‘been greeted by a hot wall of hot gasses’. Mr Cox stated that this was consistent with either a backdraft or smoke explosion rather than a flash fire relatively slowly propagating across the ground.369 CCTV footage 176 Mr Cox gave evidence that the CCTV footage indicated that there was a short term fire, such as a fireball-type event. It was also consistent with a backdraft and a smoke explosion as both result in fuel rich gasses coming out and igniting as a fireball outside the compartment.370 In respect of a flash fire, Mr Cox concluded that the same result or effect would not occur.371 Exhibit P2 – photographs 177 Mr Cox was taken to various photographs outlined in Exhibit P2. Mr Cox stated that having regard to the two photographs (17 and 18), the apparent degree of protection from the sooting or damage to the inside of the doorframe, suggested that the door was shut at the relevant time.372 178 Mr Cox noted that photograph 6 of Exhibit P2 depicted a blackening of the ceiling outside the toilet door. This image was consistent with a backdraft or smoke 367 T502.5.16. 368 T502.26.38; T503.1.9. 369 T503.9.14. 370 T503.33.38. 371 T503.2.10. 372 T507.2.8; Exhibit P2. -- 44 of 73 -- [2025] SADC 35 43 explosion fireball coming out and burning just momentarily in that area. If that had been caused by the fire, then it may be expected to be continuous from the door. In Mr Cox’s view that was consistent with a ball of fuel rich gasses excreting, igniting, and burning momentarily against the ceiling.373 The witness stated that the markings on the ceiling could not have occurred in the scenario of a flash fire.374 179 Mr Cox confirmed that photograph 26 of Exhibit P2 depicted tiles that seemed to be part of the disabled toilet.375 The overall sooting on the surface indicated an efficient combustion. Mr Cox stated that the damage to the material above the tiles suggested that the hot gas layer reached such a temperature that it was capable of causing the bubbling and blistering of the paint on that material.376 Cross-examination Background & qualifications 180 Mr Cox was awarded an honorary fellowship of the Institute of Fire Investigators, but no longer maintained involvement in that organisation.377 Mr Cox’s primary work was providing opinions to insurance companies either directly or through their loss adjusters or legal advisers.378 Mr Cox provided expert opinions as to whether the fire might be accidental or deliberate for the purpose of any insurance claim.379 Mr Cox was predominately the first to attend a scene after the MFS.380 181 Mr Cox was unable to state how many reports had been prepared where it had been concluded that the damage was as a result of a backdraft fire. 381 The witness recanted an instance of a big shed where an individual opened a door as an example of a backdraft fire where Mr Cox prepared a report. Mr Cox also recalled instances of cafeterias or fish and chip shops having explosions and finding it was due to a backdraft.382 182 Mr Cox had largely drawn upon literature when it related to understanding a backdraft scenario and other fire affects. Mr Cox had assessed the underlying theories of backdrafts.383 However, Mr Cox had not completed a laboratory reconstruction of a backdraft or a smoke explosion to study all variables. Therefore, it was appropriate to rely on the literature and assess the results detailed in the literature.384 373 T507.30.38; T508.1.3. 374 T508.13. 375 T508.25. 376 T508.28.34. 377 T517.34.38. 378 T518.3.7. 379 T518.17. 380 T522.12.16. 381 T529.37. 382 T530.1.8. 383 T533.29.33. 384 T533.33.36. -- 45 of 73 -- [2025] SADC 35 44 Backdraft fire 183 In cross-examination, Mr Cox did not disagree with the proposition that this was a deliberately lit fire. 385 Mr Cox had given evidence in court approximately 50-70 times in relation to fires.386 Some of these matters involved backdrafts and different types of explosions.387 However, Mr Cox noted that when assessing evidence of a fire, as a matter of course, it was appropriate to assess all hypotheses including a backdraft each time.388 Mr Cox could not recall a specific example of providing positive evidence that a backdraft event occurred in court.389 Notwithstanding, the limited positive evidence concluded in respect of a backdraft event in court proceedings, one aspect of each case is to answer the question 'Has there or has there not been a backdraft'.390 Difference between ventilation control and fuel controlled fire 184 Mr Cox gave evidence that a ventilation controlled fire was a fire growth of the fire determined by how much air can enter into a compartment. Contrastingly, in respect of a fuel controlled fire, its growth is determined by the nature of the fuel alone.391 Fire triangle 185 It is a requirement that there be oxygen, heat, and fuel for a fire to occur (‘fire triangle’). However, a heat source was not necessarily required. There was also a fourth component, which was the chemical reaction required to occur in a self-sustaining manner to generate the heat, this reaction involving both fuel and oxygen.392 Flash fire 186 A flash fire is 'a fire that spreads by means of a flame front rapidly through a diffuse fuel such as dust, gas or the vapours of an ignitable liquid without the production of damaging pressure'.393 Clean burn 187 A clean burn occurs when there has been a sustained fire in a ventilation controlled fire as soot is unable to condense. In a situation where there was a ventilation controlled fire, quantities of soot form on the walls, the fire then retreats back to an area where it may continue to burn at a rate controlled by the amount of air entering the room.394 Then the wall with which that flame is impinging will not 385 T518.21. 386 T535.21. 387 T535.24.28. 388 T535.29.31. 389 T536.6. 390 T536.14.18. 391 T544.8.21. 392 T544.32.36. 393 T552.35.38. 394 T568.29.33. -- 46 of 73 -- [2025] SADC 35 45 have soot on it, it will show evidence of a clean burn and so that, in itself, assists an investigator to determine where that sustained fire originated from.395 Deliberately lit fire 188 Mr Cox concluded that this fire was likely to be a deliberately lit fire due to the presence of the gasoline, the bottles containing gasoline in the ceiling and the bottle alongside the toilet, on which the primary fire plume was located.396 Based on the presence of a container of petrol near the toilet and petrol in the ceiling, Mr Cox formulated the hypothesis that it was a deliberately lit fire.397 189 Having established the fire origin, it was necessary to examine the debris in the vicinity of the fire origin to ascertain what the ignition source was and the ignition mechanism. In this case, that would involve removing the bottle and the debris surrounding the bottle and examining the bottle, the purpose of this, to establish why and how the fire was ignited.398 Sampling 190 Mr Cox understood that a liquid sample was removed from the bottle after the bottle had been uplifted, placed into a metal container, and taken back to Sergeant Wynne's facility. However, none of the other debris from around the bottle was uplifted and retained for examination, nor was there any evidence that the actual bottle itself was examined.399 Backdraft 191 Mr Cox confirmed that for a backdraft event to occur, a ventilation controlled fire within a compartment was required.400 The relevant definition from the National Fire Protection Association was 'When fires occur within rooms or structures that are relatively airtight, it is common for fires to become oxygen depleted. In these cases, concentrations appear to the airborne particles and aerosols and other flammable gases can be generated due to incomplete combustion’ and 'These heated fuels will collect in a structure where there is insufficient oxygen to allow combustion to occur and insufficient ventilation to allow them to escape'.401 Mr Cox expressed an issue with this definition. The nature of the criticism expressed by Mr Cox was due to the subjective terminology. Specifically, 'relatively airtight' does not indicate in terms of how many litres of air per minute can enter into or out of a compartment.402 395 T568.33.37. 396 T571.14.18. 397 T575.25.28. 398 T571.27.36. 399 T578.3.16. 400 T579.22.23. 401 T560.2.12. 402 T580.17.25. -- 47 of 73 -- [2025] SADC 35 46 Exhibit D23A 192 Mr Cox was shown Exhibit D23A, which was a diagram in relation to a study that occurred on a fire boat. The document arose from a study conducted involving experimental fires on board a boat where the researchers were investigating the backdraft phenomenon.403 Mr Cox confirmed that the first diagram where it stated, ‘Door Closed’, that there were fuel-rich combustion products. The oxygen was less or equal to 12%. On the outside the oxygen level was 21%.404 The experiment was conducted in what was called the pump room. The pump room that experienced the backdraft was 5.2 metres long by 2.4 metres wide and the room surrounding it which was called the buffer zone was 190 cubic metres.405 The report as to the ventilation conditions was that they made all possible efforts to make the compartment near airtight.406 193 Mr Cox agreed that for a fire that is set in a room where the oxygen level is at 21%, which is the normal atmospheric oxygen level, the fire would need to burn for some period of time, depending on other variables, in order to reach an oxygen depleted stage.407 Mr Cox accepted that this was quite a different scenario to what had occurred in the disabled toilet.408 Although, the experiment provided some information as to the principles, there were different factors including fuel source and room size present in this case.409 Ventilation controlled fire 194 Mr Cox confirmed that time would be a relevant factor.410 The time required for a fire of this type was determined by the ventilation factor and the rate at which the fire develops (the fire growth rate).411 195 With reference to the scenario presented in this particular set of circumstances, Mr Cox opined that if an assumption was made that there was a pool of gasoline of fire, it would take approximately 20 seconds or less to reach the steady state fire output that is controlled by the ventilation.412 Thereafter, it would continue to burn at that rate until either the fuel was consumed, or the ventilation conditions changed.413 Mr Cox took into account the fan as part of the calculations.414 Mr Cox’s initial estimates of the ventilation factor were based on the assumption of the size of the fan, the opening and the gaps around the door. The day prior to the trial Mr Cox attended the toilet to complete measurements of 403 T584.1.6. 404 T584.17.23. 405 T585.17.21. 406 T587.4.8. 407 T587.17.21. 408 T588.26.31. 409 T589.1.9. 410 T596.22. 411 T596.25.28. 412 T596.28.32. 413 T596.32.37. 414 T598.13. -- 48 of 73 -- [2025] SADC 35 47 the gaps around the door and the opening of the fan. Mr Cox took a photograph of the fan to modify the calculations.415 196 The size of the fire at the time that it becomes ventilation controlled is 50 kilowatts.416 In order to reach 50 kilowatts, the source bottle would need to fail in some way and start to leak fuel or, alternatively, the radiant heat from the plume would need to ignite other materials.417 When calculating the ventilation factor, it was appropriate to make an assumption that there was an infinite volume above the fan.418 197 In cross-examination, Mr Cox spoke of the establishment of a hypothesis that the fire was a ventilation controlled fire due to what was observed in the photographs, specifically the soot being deposited to the floor.419 Then to test the hypothesis, Mr Cox calculated the ventilation factor accordingly.420 Mr Cox confirmed that the pre-requisite for a backdraft is a ventilation controlled fire.421 Mr Cox opined that a flashover effect could not have occurred based on the ventilation factor calculated. If a fire does not reach the point where it has become a ventilation controlled fire, then the opening of the door should make no difference to its fire growth.422 Flash fire 198 Mr Cox stated that if there was a toilet compartment and there was gasoline splashed in the compartment, a flash fire could occur if an individual were to ignite the gasoline beneath the door, as long as there was vapour leaking from the door within the flammable range.423 Depending on the amount of vapour and a number of other variables, Mr Cox confirmed that it was possible for a person to be some distance away from the actual spillage or leak of gasoline to still be able to ignite the gasoline and cause a flash fire.424 The accused’s evidence 199 Mr Cox opined that the injuries sustained by the accused were the result of either a smoke explosion or a backdraft.425 However, Mr Cox qualifications did not extend to medical training.426 Mr Cox drew the distinction between assessing the accused as another object in a fire rather than specifically commenting on the extent of the accused’s injuries. Instead, Mr Cox was of the opinion that the 415 T598.19.33. 416 T600.14.14. 417 T600.19.27. 418 T600.33.38. 419 T602.33.34. 420 T602.35.36. 421 T605.32. 422 T606.21. 423 T612.36.38; T613.1.4. 424 T614.17. 425 T616.30. 426 T616.33. -- 49 of 73 -- [2025] SADC 35 48 accused sustained injuries that demonstrated what occurred during the fire, and therefore was within Mr Cox’s expertise to express such an opinion.427 Exhibit P2 200 When assessing photographs 17 and 18 of Exhibit P2, Mr Cox stated the damage to the back wall was the result of the temperature of the hot gas layer causing the paint to blister and burn.428 Mr Cox confirmed that this heat damage could have resulted from a backdraft effect.429 However, the witness conceded that the damage seen on the door could also be the result of the same hot gas layer following a flash fire.430 Mr Cox confirmed that the upper walls depicted in photographs 26, 27 and 28 are as a result of the hot gas layer damage, which has descended and intersected with such items as the toilet roll holder.431 201 Photograph 26 of Exhibit P2 depicted the light switch next to the doorframe. Mr Cox agreed that that appeared to be, damage sustained as a result of a gas layer or heat.432 If it had been the cause of the primary fire plume, then there would have been an associated V pattern.433 202 Photograph 32 depicted the roof space and the remnants of the fan in the middle of the ceiling.434 Heat damage was again present in this photograph.435 203 Photograph 6 depicted sooting damage to the roof of the area above the entry to the toilet. Mr Cox believed that this damage was caused as a result of a fireball coming out of the toilet door.436 In general terms the longer smoke was leaking from a compartment, the more likely it was of a greater amount of soot being deposited above the doorframe.437 Height of fire 204 Mr Cox gave evidence that if there was petrol splashed on the ground and a person walked around the room, this would only change the height of the stratified layer by a few centimetres and would not cause vapours to mix that creates an ignitable layer at a greater height.438 Mr Cox confirmed that the height of the hairdryer and the height of the light switch are unlikely to have been ignition sources, given the amount of time that appeared to be involved in this incident.439 427 T616.34.38. 428 T624.9.10. 429 T624.36. 430 T625.13. 431 T625.30.33. 432 T626.35.38. 433 T626.35.38. 434 T627.30. 435 T627.30. 436 T629.11.14. 437 T631.16.18. 438 T645.23.31. 439 T650.8.12. -- 50 of 73 -- [2025] SADC 35 49 Accused evidence 205 The accused’s evidence was tendered as part of Exhibit P7 from the previous trial. She did not give evidence at this trial. 206 The accused attended the shopping precinct with two bags. One of those was clearly the backpack that the accused was wearing and the other bag, the prosecution suggested, is a calico or canvas shopping bag that was later seen burnt or melted to the backpack. 207 The accused went to visit her mother at the Australia Post shop on the day in question. She was going to get some chicken and to see if her partner’s parcel had arrived. Prior to entering her mother’s shop, she purchased a Keno ticket from the nearby booth. The accused described the visit as a social visit. 208 Before the fire, the accused described leaving the Australia Post shop to take some washing to her car. The accused’s car was directly outside the entrance of the shopping precinct.440 The accused walked down past the toilets and went to the female toilets. The accused attended the female toilets to check her face as she had been crying, as a consequence of an SMS argument with her daughter. The accused heard a noise in the disabled toilets and wanted to know what it was. The accused stated that the door was ajar and was sticking out a little bit. The accused did not see smoke coming from the room and did not recall if the doorhandle was hot. When the accused opened the door further, the wind of the firewall as described came out. The accused stated, ‘I did not know it was a fire at the time, just like a big gust of heat’. 209 The accused observed that her cardigan was melted and she did not really know what was going on. The accused has very little recollection of what occurred in the aftermath. When asked ‘do you feel your memory is good or are you not sure?’. The accused responded ‘I’m not sure what my memory is’. 210 The accused denied lighting the fire. Under cross-examination, the accused denied knowing that there was not CCTV in the area of the toilets. She said the door to the disabled toilet was ajar, ‘just sticking out a little bit’. The accused accepted that she had her backpack with her, but denied pouring petrol around the disabled toilet and lighting the matches. It was suggested that she was burnt by taking out matches and being burnt by a vapour fire when she lit the fire, which was denied, as was the suggestion that she placed the petrol filled bottles in the roof. Addresses of Counsel Prosecution closing address 211 Ultimately the prosecution submitted that the only reasonable hypothesis as to how the accused came to be burnt by the fire and how her DNA profile was a 440 Exhibit P2. -- 51 of 73 -- [2025] SADC 35 50 likely contributor to the DNA samples was that accused was the person who filled the bottles, placed them in the roof inside the toilet and was burnt by being in close proximity to the fire after the accused had deliberately set the fire alight. 212 The prosecution case, based on circumstantial evidence, was that after leaving the post office, the accused entered the disabled toilet, took the fan cover off, took the bottles containing petrol from the bag and placed them in the roof space and put one of the bottles next to the toilet. As a result of the distribution of petrol, there were flammable vapours that distributed or diffused into the room. These vapours were ignited when the accused set a match alight in order to set the fire in the disabled toilet. The accused was subsequently burnt by a flash fire, as was her backpack and the black shopping bag the accused was carrying. 213 Notwithstanding whether I accept that the fire was from a backdraft effect on the defence case, or a flash fire on the prosecution case, ultimately the prosecution submitted that the Court could conclude that the accused was the person who deliberately lit and caused the fire beyond reasonable doubt. Contamination of DNA evidence on bottles 214 The prosecution submitted that there was strong evidence to support the hypothesis that the DNA profile generated was consistent with the accused’s DNA being deposited directly on the items that were sampled. Therefore, I can reject any innocent explanation for the presence of that DNA profile, having regard to all relevant evidence. 215 The prosecution submitted that the results of the DNA evidence on the two bottles are consistent with the accused having touched the bottles, twisted their lids, and filled the bottles with petrol. There was extremely strong statistical probability in favour of the accused’s DNA profile contributing to the mixed DNA profile sample extracted from the lids of the 2 litre Pepsi bottle and 2 litre water bottle. The prosecution submitted that Sergeant Wynne gave earnest and truthful evidence about the directions provided to the other officers who handled exhibit items to minimise the possibility of contamination. It was submitted that both Brevet Sergeant Wynne and Commander Ruxton did not believe that they touched the lids of the bottles. 216 Sergeant Wynne was responsible for managing the crime scene. Sergeant Wynne directed Brevet Sergeant Murphy and Commander Ruxton to assist with processing and collecting the various exhibits.441 All police officers were trained in relation to the standard practice of DNA contamination. The prosecution submitted that there was no evidence to suggest that Brevet Sergeant Murphy, Sergeant Wynne or Commander Ruxton departed from what was usual practice. 441 Exhibit P6. -- 52 of 73 -- [2025] SADC 35 51 217 Sergeant Wynne wore two pairs of gloves and consistently took off the outer pair of gloves in between handling different items. Sergeant Wynne instructed Commander Ruxton to not touch the lids and gave evidence that the bottles were swabbed by Brevet Sergeant Murphy. Sergeant Wynne did not see either Commander Ruxton or Brevet Sergeant Murphy make any contact with the lids other than by swab, albeit that Sergeant Wynne did not have the bottles under observation throughout the entirety of the crime scene investigation. 218 The prosecution submitted that the defence hypothesis that the DNA was transmitted through aerosol transfer was contrary to Dr Taylor’s evidence.442 Specifically, the prosecution referred to the evidence of Dr Taylor, referring to a study where if a particular person spends a significant period of time in the vicinity of an object whether it will affect and how much DNA may be deposited by aerosol transfer. Dr Taylor also gave evidence that clothing tends to trap DNA or skin shedding.443 CCTV footage depicted the accused wearing a pink cardigan and jeans. Therefore, the prosecution asserted that a minimal amount of the accused’s skin was exposed at the time, which would affect and minimise any aerosol transfer. The prosecution further submitted that the brief time that the accused was in the area, lack of activity, clothes covering the majority of body, being placed on a stretcher and wheeled out rather than again walked through the scene, suggested that the probable scenario and only reasonable scenario that the accused’s DNA was a likely contributor to the two reference samples was because the accused had twisted the bottle lids shut before placing them in the ceiling space of the disabled toilet. Cause of the fire 219 In relation to the cause of the fire, the prosecution submitted that it was a flash fire that was lit by the accused. 220 It was accepted both by the prosecution, defence counsel and the respective expert witnesses that the fire was a deliberately lit fire. The presence of the bottles and the petrol within those bottles led both Sergeant Wynne and Mr Cox to the conclusion that they had been introduced by a person with the intention of causing the fire. 221 The prosecution submitted that it was entirely plausible and perhaps likely that the exhaust fan cover had been removed prior to the fire starting and that would be consistent with the bottles of petrol being located in the roof. Therefore, the cover had been removed to secure the bottles in the ceiling. 222 The prosecution asserted that the lack of discernible low order explosive effect, namely: the doors were still in place, the walls were in place, there was no damage to the compartment, and nothing had been moved from the small bin that had sustained heat damage, ultimately suggested that what had occurred in the 442 T340-341. 443 T341. -- 53 of 73 -- [2025] SADC 35 52 disabled toilet was a flash fire. The flash fire was a result of diffusion of petrol vapours after the lighting of a match, which then subsequently caused other items in the room such as the toilet roll and the power socket to ignite in flames. The combustion of these items was responsible for the black smoke that was being produced from the toilet confirmed by witnesses at the scene. 223 It was submitted that even if the evidence does not exclude that there was a reasonable possibility that the incident occurred as a consequence of the backdraft effect, the prosecution has still proved its case on the basis that the accused could have closed the door, set the fire and then returned and re-opened the door, thus causing the backdraft effect as submitted by defence counsel. 224 Other circumstantial evidence, such as the accused being in the area and being burned also further supported the proposition that the accused had the opportunity to commit the offence. The accused was unaccounted for approximately six minutes in the CCTV footage. The accused had a backpack and a bag which the prosecution submitted contained the bottles of petrol. In the time that the accused is unaccounted for, the inference to be drawn is that the accused had attended the toilet, placed the bottles in the roof and set fire to the bathroom. 225 The prosecution submitted either the accused was a most unfortunate person who had found themselves in the wrong place at the wrong time or that the accused was the person who put the petrol bottles in the toilet, as evidenced by the accused’s DNA profile being likely contributors to the reference samples of the two bottles and therefore that the accused had caused the fire damage by deliberately lighting the fire. Sergeant Wynne 226 The prosecutor submitted the evidence of Sergeant Wynne concluded that the fire was a deliberately lit fire by a person igniting an accelerant. Sergeant Wynne located a box of matches in the doorway. There was an active or sustained fire that had been burning in the area of the bottle next to the toilet. The industrial toilet roll was burning, and the bin nearby had melted. Sergeant Wynne estimated that given the damage to the toilet roll, that the fire had not been burning for a particularly long time. Sergeant Wynne had regard to the heat damage to the cord and to the power point near the hair dryer. Both witnesses could exclude the possibility of the hair dryer being a possible ignition source. 227 The prosecutor submitted Sergeant Wynne was of the view that the exhaust fan cover was removed and may have been placed on the floor before the fire started but could not be certain. Sergeant Wynne formed the opinion that the sooting above the toilet door was a result of smoke escaping out of the room after the flash fire had occurred and while the fire was still actively burning. It was submitted by the prosecutor that whilst Mr Cox is of the view that this was a result of a fireball emanating as a result of the backdraft effect, Mr Cox did not exclude the possibility that it could have been from active burning after the event. -- 54 of 73 -- [2025] SADC 35 53 228 Sergeant Wynne was unable to confirm whether the light from the CCTV footage was a light or a fire. However, coupled with all evidence, it was not in dispute that it was a fire. Sergeant Wynne never firmly expressed the opinion that the fire was a backdraft, but preferred the hypothesis that it was a flash fire. As mentioned, the prosecution submitted that coupled with all the evidence, that the flash fire was the cause of the fire. Mr Cox 229 The prosecution emphasised that whilst Mr Cox criticised Sergeant Wynne for not adhering to the proper scientific method of fire cause investigation, Mr Cox did not deny that the petrol was set alight in some manner. The location of the matches being a foreign item, and a known or common ignition source, suggested that it was entirely reasonable for Sergeant Wynne to conclude that the matches were used to ignite the accelerant. Mr Cox agreed with Sergeant Wynne that the V shape pattern on the toilet cistern indicated that there had been a sustained or active flame burning below that pattern. Mr Cox could not state with certainty or refer to statistics to confirm that a backdraft fire was a relatively uncommon event or give any specific examples of where the witness had given positive assertions, that a backdraft event had occurred. All those scenarios referred to in Mr Cox’s evidence, including the boat experiment that was subject to Exhibit D10, were conducted in environments where intentional efforts had been made to ensure the relevant compartment was as airtight as possible. This was to ensure that there was oxygen depletion at a substantial rate to be able to monitor a backdraft effect. Mr Cox accepted that there were gaps under the door and smoke was rising. Mr Cox did not completely exclude the possibility of a flash fire but preferred the view of a backdraft fire. 230 Mr Cox suggested that an experienced arsonist might use a wick or some other form of delay to set alight the accelerant. However, it was not the prosecution’s case that the accused was an experienced arsonist, although Mr Cox suggested that the volume of the petrol in the bottle next to the toilet and the roof indicated an experienced or knowledgeable arsonist who wanted to cause some damage. The Prosecution submitted that it does not take an experienced arsonist to know that petrol was flammable and that the more petrol there was, the more fire there was likely to be. 231 Notwithstanding, whether the fire was caused as a result of a flash fire or a backdraft event, the accused was in the vicinity of the scene of the fire immediately before it was set a light, was badly burned by the fire and petrol was located on her jeans, albeit was accepted by the prosecutor it could not be determined whether that was direct petrol or vapour. Accused evidence – previous trial 232 The accused’s version was that in the six minutes or so after leaving the Australia Post shop, was that on the day the accused had attended to pick up a parcel and buy some chicken. The accused attended with two bags. One of those -- 55 of 73 -- [2025] SADC 35 54 was clearly the backpack and the other bag the prosecution suggested was a calico or canvas shopping bag that was subsequently seen burnt or melted to the backpack. 233 The evidence of the accused was that she opened the door further, the wind of the firewall as she described came out. The accused stated, ‘I did not know it was a fire at the time, just like a big gust of heat’. The prosecution submitted that if a finding was made that the door was closed, that was inconsistent with the accused’s evidence, and I must consider whether this undermines the accused’s credibility and reliability. 234 It was submitted that, at no point does it appear that the accused received any package from her mother whilst attending the post office, nor does the accused appear to have any additional items when leaving the post office. Therefore, the accused must still have had the two bags, being the backpack and the calico bag which are subsequently damaged in the fire. It was submitted that she also appeared to reach into the backpack and touch something prior to leaving and walking down towards the disabled toilets. 235 The prosecution submitted that the accused did not directly go to acquire chicken from Drakes Foodland. The prosecution asserted that the accused would be familiar with the positions of the CCTV at the shopping complex. 236 Based on the accused’s height and weight, it was plausible for the accused to have easily stood on the toilet or sink, pulled the fan cover off, left it on the floor and placed the plastic bottles into the ceiling space. 237 The prosecution submitted the CCTV footage revealed that the accused’s bags appeared just as full as they did when the accused entered as to when leaving the post office. The accused collected washing, but Ms Sobey gave evidence that would usually be packaged in another bag ready for collection. The accused did not leave with another bag other than the two original bags brought with her. 238 Ultimately the prosecution submitted that the evidence of the accused was not plausible and does not fit with the remainder of the objective evidence and other witnesses. Opportunity 239 The prosecution highlighted the accused was unaccounted for after heading in the direction of the fire for approximately six minutes before the accused reappeared shortly after the orange flash. The accused had a full backpack and shopping bag before leaving. It was submitted her mother returned with an empty bag upon return. The accused was within close proximity to when the fire was light based on the significant burns sustained. Thus, the prosecution submitted that the accused had ample opportunity to commit the offence. -- 56 of 73 -- [2025] SADC 35 55 Defence closing address 240 Defence counsel submitted that the prosecution had not excluded as a hypothesis that it was reasonably possible that the accused was burnt by a fire that was already burning in the disabled toilet, a fire that the accused did not light, and the accused was burnt in the process of standing at the door of the toilet by reason of the backdraft or smoke explosion event. Defence counsel further submitted that the accused’s DNA innocently came to be present on the bottles due to innocent transfer by the officers who were handling the exhibits and/or by potential aerosol transfer. Contamination of DNA evidence on bottles 241 Defence counsel submitted that there are two potential propositions as to how the accused’s DNA profile may have innocently contributed to the DNA mixed profile of the two bottles. Firstly, the possible contamination by intermediary transfer of the police officers when they were handling the bottles. Secondly, possible contamination by aerosol transfer. 242 Mr Wilson submitted that there are a number of potential ways that the accused’s DNA could have been innocently deposited that arise on the prosecution’s own evidence. Commander Ruxton’s handling of the bottles, wearing one pair of gloves, what Commander Ruxton touched and whether surfaces and items that Commander Ruxton touched had the accused’s DNA. This was one issue that creates a scenario whereby the DNA could have been transferred onto the bottle lid itself in the process of removing or handling the bottles. Sergeant Wynne 243 Sergeant Wynne was involved in the swabbing process in so far as noting down what was swabbed, but in cross-examination the witness appeared to have assisted Brevet Sergeant Murphy in terms of holding the vial that the swab was put in or even removing the lid off the vial and holding it and then screwing it back on. Therefore, if Sergeant Wynne was using the same pen the whole time, then the Court cannot be satisfied, particularly in circumstances where Sergeant Wynne handled a bag that potentially contained the accused’s DNA after being badly burnt, that Sergeant Wynne had not introduced the accused’s DNA as part of the swabbing process. 244 Mr Wilson submitted that there was uncertainty as to how the vials and lids were handled and by whom and there are inconsistences in the evidence of Commander Ruxton, the MFS officer, Brevet Sergeant Murphy, and Sergeant Wynne as to who handled the bottles and who performed the swabbing due to inadequate notetaking or record keeping of the movement and handling of exhibits within the scene. 245 Further, defence counsel submitted that the container that held items to be DNA tested was placed on the ground relatively close to the toilet where the accused was badly burnt and in the area that the accused had moved through. -- 57 of 73 -- [2025] SADC 35 56 Consequently, there was a further possibility of contamination. Sergeant Wynne used the same pen throughout the duration of the investigation. The witness had no issue taking notes with gloves. Accordingly, the pen was a potential source or a vector for the accused’s DNA at least from the moment of receiving the paper bags from Detective Webber and making a note of the clothing received. 246 As to the area where the exhibits were processed, Sergeant Wynne operated on a misconception that as the area had been cordoned off and there was a degree of control over personnel who came in and out, it therefore somehow made it an appropriate area to conduct the examination in. Consequently, the setup of the examination station for the evidence that was collected was inadequate. This was further supported by the fact that there was skin on the window, possible skin under the trolley on the floor, blood on the floor and the accused had walked through the area. Many individuals were entering the space, and this increased the likelihood of there being airborne DNA. 247 Sergeant Wynne’s evidence was also in conflict with Commander Ruxton’s regarding the procedure for the removal of the bottles. Namely, they were not in lockstep during the course of their attendance together. There are no notes in respect of who handled the bottles, how they were removed or who took the swabs. Sergeant Wynne accepted, with the benefit of hindsight that further notes of who removed the bottle should have been recorded as part of the investigation. Commander Ruxton 248 Defence counsel emphasised, Commander Ruxton thought it was unusual that Sergeant Wynne was changing gloves continuously. Defence counsel submitted that it was theoretically not difficult to imagine a situation where Commander Ruxton touched surfaces such as the door, doorhandle or fan in the disabled toilet and the accused’s DNA was on such surfaces, before Commander Ruxton touched the bottles. Commander Ruxton also wore the same pair of gloves throughout the investigation at the scene and did not employ the same precautions that Sergeant Wynne adopted. 249 It was submitted that it was unclear exactly the surfaces and objects touched by Commander Ruxton at the scene prior to the removal of the bottles from the roof. Commander Ruxton was not certain if the door to the toilet was open or not upon arrival, and it follows that if Commander Ruxton was unsure whether it was open or not that there was a realistic possibility that Commander Ruxton may have touched the doorhandle before retrieving the bottles. Commander Ruxton’s evidence was that the bottles were removed one by one and handed to one of the crime scene investigators. Again, Commander Ruxton wore the same pair of gloves when completing this process. 250 Further, Commander Ruxton removed the exhaust fan to obtain access to the bottles in the roof. Contrastingly, in cross-examination, Commander Ruxton stated that the bottles were removed whilst the fan was still in the roof. Commander Ruxton noted that there were no screws in one of the clamped ends of the ceiling -- 58 of 73 -- [2025] SADC 35 57 fan. Defence counsel submitted that this was significant in terms of that there appeared to be evidence that to remove the fan a screw had been removed previously. Commander Ruxton remembered seeing a screw on the ground. However, no screwdriver was found on the accused. There was no evidence of a screwdriver in accused’s backpack, nor in the car that was searched, nor the accused’s residence. Brevet Sergeant Murphy 251 Brevet Sergeant Murphy was a police officer with 47 years’ experience and had been a crime scene examiner for 10 years since the time of the incident. Mr Murphy had attended thousands of crime scenes and had completed hundreds of swabs of items for DNA. Brevet Sergeant Murphy’s training included the importance of detailed notes on the chain of evidence. Defence submitted if Brevet Sergeant Murphy handled any item in terms of collecting or sampling, this would be marked with initials. 252 Brevet Sergeant Murphy did not double glove unlike Sergeant Wynne. Thus, the failure to adhere to and implement precautions in relation to the handling of the exhibits further suggested that there was a reasonable possibility that the items were contaminated. Dr Duncan Taylor 253 The 2 litre Pepsi bottle had three DNA profile contributors, and the 2 litre water bottle had two DNA profile contributors. There was no evidence as to whether there was a common contributor other than there being extremely strong support that the accused’s DNA was a contributor to the mixed samples. In respect of the swabs from the lids, only five of the six swabs were tested. 254 Dr Taylor gave evidence regarding aerosol transfer being possible. At any given time, small amounts of cells containing DNA are floating around in the area and can cause aerosol contamination. 255 Defence counsel submitted that Dr Taylor was a well-qualified expert who was careful and considered. Whilst there were no studies on the topic of shedding for severe burns, it was common sense that it would lead to greater shedding in terms of being distributed onto the clothing, which then dovetails into the likelihood of a bag that Detective Schuurmans retrieved as being a rich source of DNA. Subsequently, some of the DNA could have been deposited back onto the paper bag, taken to the crime scene, and handled by officers at the scene. 256 Dr Taylor stated that placing any part of an object to be swabbed on the floor was suboptimal in the circumstances. Dr Taylor accepted that it was possible skin cells or other biological material were on the floor of the shopping centre. The way in which the lids was handled at the scene may have influenced the prospects of contamination. Given that the lid could have been contaminated, Dr Taylor opined -- 59 of 73 -- [2025] SADC 35 58 that there was a possibility of the outside of the sample file to contaminate the contents of the file when FSCSA tested the DNA. Cause of fire 257 Defence counsel suggested that the orange flash coincided with the accused having opened the door on a pre-existing ventilation control or oxygen depleted fire set by another individual and thereafter opening the door, the accused suffered burns as a result of a fireball caused by a backdraft. The prosecution’s own expert, Sergeant Wynne, could not exclude the possibility of a backdraft. Mr Cox 258 Defence counsel’s overarching submission was that Mr Cox’s credentials far exceeded that of Sergeant Wynne’s. Mr Wilson stated that Mr Cox was confident, careful, clear and to the extent that there was a divergence in the opinions, the Court should prefer Mr Cox’s evidence in respect of the cause of the fire. 259 Defence counsel drew the Court’s attention to the fact that Sergeant Wynne was not familiar with the notion of a ventilation controlled fire. Sergeant Wynne did not have the expertise or knowledge to be able to calculate the ventilation factor, which was an important check that Mr Cox did as a means of testing the hypothesis that was reached. Thus, Sergeant Wynne’s knowledge was, respectfully, inferior to that of Mr Cox. 260 Defence counsel stated that there was further difficulty with accepting the flash fire scenario given that Sergeant Wynne gave no positive evidence that would explain how the flash fire scenario would account for the burns that the accused sustained. Sergeant Wynne did not possess a great deal of experience and knowledge in respect of backdraft fires. The evidence of Sergeant Wynne indicated a degree of uncertainty in respect of how a backdraft fire may have ignited in the circumstances. CCTV 261 Defence counsel addressed the issue of the CCTV footage regarding the accused movements prior to the fire. The accused attended the post office, placed the bag on the counter, leaving it unattended and was depicted on CCTV. Defence counsel submitted that this behaviour was inconsistent with a person that was aware of where every camera was. Good character evidence 262 Good character evidence was received in the form of the transcripts of the character witnesses that were called at the previous trial.444 Defence counsel submitted that good character combined with the absence of motive raises itself a 444 Exhibit D28. -- 60 of 73 -- [2025] SADC 35 59 doubt of the accused’s guilt aside from the other difficulties in the prosecution case which are not sufficient to prove the accused’s involvement. Ms Sobey 263 Defence counsel highlighted that Ms Sobey did not smell anything out of the ordinary within the shop. This was significant against the background of the prosecution case being that the bottles were with the accused in the shop for upwards of half an hour, including the accused leaving the backpack unattended on the front counter for up to five minutes. Ms Sobey gave evidence that it was common for the accused to have a folder of documents as well as carry a bag or a backpack. It was common for the accused to visit her mother to receive washing and ironing. Thus, there was nothing unusual as far as Ms Sobey’s evidence was concerned regarding the accused attendance at the Post Office. Detective Schuurmans 264 Detective Schuurmans was provided at the hospital a plastic bag containing all of the accused’s clothes. Detective Schuurmans then removed, wearing gloves, one item of clothing, placed it into a brown paper bag with gloves on, folded the brown paper bag over and sealed it. Detective Schuurmans candidly stated that the changing of gloves did not occur during this process as it was for residue testing so ‘there was no need to change them’. 265 Ultimately, defence counsel submitted that, having regard to the real possibility of contamination or there being an innocent explanation for the DNA evidence said to implicate the accused, together with the correct conclusion that the fire was a backdraft or smoke explosion, and assessing the evidence as a whole, the prosecution has not excluded as a reasonable possibility any hypothesis consistent with innocence. Circumstantial evidence 266 It is well established that where a case is premised entirely on circumstantial evidence, the trier of fact is required to consider the whole of the evidence in assessing whether the prosecution have proven the charges beyond reasonable doubt. As stated by Dawson J in Shepherd v The Queen:445 As I have said, the prosecution bears the burden of proving all the elements of the crime beyond reasonable doubt. That means that the essential ingredients of each element must be so proved. It does not mean that every fact — every piece of evidence — relied upon to prove an element by inference must itself be proved beyond reasonable doubt. Intent, for example, is, save for statutory exceptions, an element of every crime. It is something which, apart from admissions, must be proved by inference. But the jury may quite properly draw the necessary inference having regard to the whole of the evidence, whether or not each individual piece of evidence relied upon is proved beyond reasonable doubt, provided they reach their conclusion upon the criminal standard of proof. Indeed, the probative force of a 445 (1990) 170 CLR 573 at 579-580. -- 61 of 73 -- [2025] SADC 35 60 mass of evidence may be cumulative, making it pointless to consider the degree of probability of each item of evidence separately. 267 I remind myself of the remarks of Gummow, Hayne and Crennan JJ in R v Hillier:446 … It has often been said that a jury cannot be satisfied beyond reasonable doubt on circumstantial evidence unless no other explanation than guilt is reasonably compatible with the circumstances. It is of critical importance to recognise, however, that in considering a circumstantial case, all of the circumstances established by the evidence are to be considered and weighed in deciding whether there is an inference consistent with innocence reasonably open on the evidence. [footnotes omitted] 268 In a circumstantial case, there will be evidence of matters which, looked at in isolation from other evidence, would yield an inference compatible with the innocence of the accused. A circumstantial case is not to be considered in piecemeal fashion. It is the combined strength of all of the circumstances that needs to be assessed. Lest there be any uncertainty, this is the approach I have adopted in this case. Primary topics of controversy 269 Whilst I must assess the evidence as a whole, as I am required to, there arose two primary areas of controversy at trial. First, the potential contamination of the DNA evidence said to implicate the accused which was located on the two lids from bottles located in the roof of the disabled toilet. Second, the specific cause of the fire, namely whether it was a flash fire or a ventilation controlled (backdraft or smoke explosion) fire. I will assess each of these issues whilst having particular regard to the expert evidence that was lead at trial as well as all other evidence before the Court. 270 The prosecution case is that on 23 December 2013 the accused took seven soft drink bottles filled with petrol into the disabled toilet at the Parafield Plaza shopping centre, placed six bottles through the ceiling fan space into the ceiling space, splashed petrol from the seventh bottle around the room and struck a match igniting the petrol. The prosecution case was that the accused suffered serious burns to her chest, back, arms, knees, and feet as a result of the ‘explosion’ of the petrol inside the room. 271 Ultimately, the prosecution submitted that I must consider whether the accused was so unfortunate as to find herself in the wrong place at the wrong time after somebody else had lit the fire in the disabled toilets and then as a result of her burns, distributed DNA across the floor of the shopping centre which was in turn then mixed up and landed on only two of the bottles. A similar submission was made in relation to the possibility that there was some alternate innocent explanation that caused the accused’s DNA to be transferred to the bottle lids. 446 (2007) 228 CLR 618 at [46] per Gummow, Hayne and Crennan JJ. -- 62 of 73 -- [2025] SADC 35 61 Contamination 272 I deal first with the presence of a DNA profile on two of the bottle lids relied upon by the prosecution as a piece of circumstantial evidence implicating the accused as the arsonist. As the prosecutor correctly observed during her closing address ‘the accused’s DNA on the lids of the bottle and the petrol is, of course, a fundamental aspect of the prosecution case’.447 The accused submits that it cannot be excluded that the implicatory DNA profiles are present as a consequence of contamination and/or innocent deposition. 273 I have regard to the agreed facts which confirm that fluid samples were taken from each of the six bottles located at the scene. All of the bottles were found to contain petrol. 274 DNA matching the accused was located on the lids of two of the bottles retrieved from the roof space, being the Pepsi bottle and on the water bottle. Insufficient DNA for analysis was located on the Coke Zero, Coca Cola and V8 juice bottles that were laying down in close proximity to the floor. Another Coca Cola bottle lid appears to have been swabbed (according to the exhibits list), but no DNA results were before the Court in relation to this particular swab. 275 Commander Ruxton’s handling of the bottles requires consideration. 276 Commander Ruxton wore the same single pair of gloves for the duration of his ‘time at the scene’. Those gloves were put on before Commander Ruxton entered the disabled toilet. In evidence, Commander Ruxton stated: • That he believed the door to the toilet was open, but could not be sure; • That the bottles were taken out carefully; • That he was not aware of touching the lids of the bottles and can’t recall whether he touched them or not; • That he and Sergeant Wynne shared the same camera when taking photographs at the scene; • That he saw Brevet Sergeant Murphy changing gloves.448 277 Sergeant Wynne stated in his evidence: • That upon reflection, both he and Brevet Sergeant Murphy were likely involved in the swabbing process; 447 T689.13-15. 448 T935. -- 63 of 73 -- [2025] SADC 35 62 • That whilst Sergeant Wynne was changing gloves between handling potential exhibits, Brevet Sergeant Murphy was not. 278 Both Commander Ruxton and Sergeant Wynne could not categorically account for the handling of these exhibits, nor exclude the real possibility of material contamination of the exhibits. Brevet Sergeant Murphy has no specific recollection as to his handling of the exhibits. 279 There are inconsistences between Sergeant Wynne, Commander Ruxton and Brevet Sergeant Murphy regarding the precautions taken to prevent contamination and the sampling process. They are summarised as follows: • Sergeant Wynne states he instructed Commander Ruxton to only handle an area that was not the lid of the bottle. Contrastingly, Commander Ruxton stated that he was not directed by Sergeant Wynne to handle the bottles a certain way. • Sergeant Wynne gave evidence that Commander Ruxton came down the ladder each time, walked the bottles up the corridor and placed each individual bottle down in the sampling area before returning to the toilet to retrieve the next bottle. Conversely, Commander Ruxton gave evidence that each bottle was passed down to either Sergeant Wynne or Brevet Sergeant Murphy and he remained on the ladder. • Commander Ruxton stated that he took all of the photographs at the scene. Conversely, Sergeant Wynne stated that he and Commander Ruxton would each have taken photographs and handed the camera back and forth throughout the course of the investigation (Ruxton without changing gloves). • Commander Ruxton observed the swabbing process. However, Sergeant Wynne stated he was not in lockstep with Commander Ruxton during the investigation. They would consult each other on matters but they were not physically with each other for the whole investigation at the scene. • Sergeant Wynne was only involved in the swabbing process in terms of taking notes. However, under Cross-examination, Sergeant Wynne accepted that he may have assisted Murphy in this process and held the vial that the swab was put in or even taking the yellow lid off the vial and holding it and then screwing it back on. 280 These inconsistencies are to be considered in circumstances where Brevet Sergeant Murphy gave evidence in general terms that he had little independent recollection of this particular investigation and did not make any notes of his involvement in the investigation. -- 64 of 73 -- [2025] SADC 35 63 281 There is uncertainty and a lack of note taking in relation to how the vials used for taking the swabs and the bottle lids were handled and by whom. There are inconsistences in the evidence of Commander Ruxton, Brevet Sergeant Murphy, and Sergeant Wynne as to who handled the bottles, how the bottles were handled, how they were transported to the processing area and how the swabbing was performed. The evidence leaves open as a very real possibility (to say the least) that Commander Ruxton’s hands and hence single pair of gloves came into contact with surfaces of the disabled toilet area such as the door or door handle, where the accused’s DNA may have been as a consequence of her accessing the toilet, before he then handled the lids of the bottles. That being a reasonable possibility, I am unable to exclude the hypothesis that the accused’s DNA came to be on the bottle lids by way of secondary or tertiary transfer. Put another way, the interaction Commander Ruxton had with the scene and his handling of exhibits gives rise to the distinct possibility of contamination. Contamination via aerosol transfer 282 The location which Sergeant Wynne selected to test the bottles also exposes the real possibility of contamination. The bottle lids were staged in a location on the ground in close proximity to the toilet area where the accused was badly burnt and subsequently moved through on her way back to the post office. The lids were swabbed in this area. Dr Taylor confirmed that this examination station may have been inadequate or not ideal in terms of preventing contamination. As much was accepted in the prosecution closing address. 283 In respect of aerosol transfer, Dr Taylor was not able to exclude that someone who is severely burnt might shed their DNA at a greater rate than someone who is not, albeit that he was not aware of any studies regarding whether shedding increases for burnt victims. I have regard to the limitations expressed on this aspect of the evidence of Dr Taylor. 284 Dr Taylor gave evidence on the topic of aerosol transfer. A summary appears in these Reasons. I have assessed the evidence on aerosol transfer in the context of the circumstantial evidence as a whole. Having undertaken that wholistic analysis, I am unable to exclude as a reasonable possibility that there may have been innocent deposition of the accused’s biological material onto the relevant bottle lids via aerosol transfer. The location of the exhibit processing area in close proximity to the toilet, the placement of the bottles onto the floor in that area, the evidence of Sergeant Wynne that Commander Ruxton walked each of the individual bottles to the processing area, one at a time, thereby permitting differential deposition of airborne biological material across the individual exhibits, the evidence that the accused was badly burnt in the immediate vicinity shortly prior, together with the evidence of Dr Taylor means that aerosol transfer is a reasonable possibility. 285 Notwithstanding that it is highly suspicious that the accused’s DNA was a likely contributor to the lids of two bottles that were originally located in the -- 65 of 73 -- [2025] SADC 35 64 ceiling of the disabled toilet, given the practices adopted by the forensic investigators, inconsistences on their evidence, particularly as to the handling of exhibits, lack of contemporaneous notes, the unsatisfactory location of the exhibit station which was set up nearby to the disabled toilet and the accused’s movement in close proximity to the disabled toilet and having regard to all of the evidence, I am unable to exclude innocent deposition as a reasonably possible explanation for the DNA evidence. Contamination of the exhibits is a reasonable alternative hypothesis in the particular circumstances of this case. In reaching this conclusion, I am satisfied that the evidence and submissions of defence are more than mere conjecture.449 Cause of the fire 286 When assessing the cause of the fire, I have regard to the evidence of Sergeant Wynne and Mr Cox, together with the entirety of the evidence. 287 Mr Cox’s qualifications and experience outweighs that of Sergeant Wynne’s. Mr Cox was an impressive witness. The prosecution expert, Sergeant Wynne, could not exclude the possibility of a backdraft. Sergeant Wynne did not possess the same level of knowledge in relation to backdraft or ventilation controlled fires. Sergeant Wynne was not able to complete calculations in respect of ventilation controlled fires. 288 Whilst Mr Cox made a point of criticising Sergeant Wynne for not excluding every possible hypothesis of an ignition source, both Sergeant Wynne and Mr Cox were in agreeance that the electrical appliances within the room could be excluded as possible ignition sources. 289 Both Sergeant Wynne and Mr Cox were in agreeance that the damage to the walls, the hair dryer and the light switch were the result of the heat from the hot gas layer that was radiating either from the fire, or as Mr Cox concluded from a backdraft effect. Both experts agreed the fire, whatever its form, was deliberately lit. 290 Mr Cox gave evidence that the injuries sustained by the accused were more consistent with a backdraft effect or smoke explosion, rather than a flash fire. If a flash fire were to occur, the height of the flame would have been much lower, about 10-20cm from the ground. Mr Cox also noted that the damage to the door frame of the disabled toilet and the soot that was present on the door frame was consistent with a backdraft effect occurring. Thus, the accused’s injuries and damage within the disabled toilet are consistent with a backdraft effect occurring, as opposed to a flash fire. In making this observation, of course, Mr Cox is not a medical practitioner. However, it is the cause of the injury (i.e. the nature of the fire) that is the focus of the evidence, not the medical detail of the injury, which is a burn or burns. 449 R v Baden-Clay (2016) 258 CLR 308 [47]. -- 66 of 73 -- [2025] SADC 35 65 291 Further, the orange flash captured on the CCTV supports the hypothesis that the accused opened the door on a pre-existing ventilation controlled or oxygen depleted fire and suffered burns as a result of a fireball caused by a backdraft event. 292 This hypothesis is also consistent with the civilian witnesses at the shopping centre not observing anything unusual prior to what became the obvious fire event causing the injuries to the accused. For practical purposes, the closed door of the toilet concealed the ventilation controlled fire prior to the door being opened, leading to the backdraft, which caused the injuries to the accused. Evidence of bags 293 The prosecution submitted that the Court should draw an inference that the bags carried by the accused visible on the CCTV footage contained the bottles filled with petrol. Again, I consider this submission in light of the entirety of the evidence. The CCTV footage is not clear enough to ascertain the contents of the bags. The witness, Ms Sobey, stated that the accused would typically arrive at the Australia Post shop carrying a bag as part of her regular attendances at her mother’s shop. The actions of the accused, first, placing the bags on the service counter at the Australia Post shop then, second, leaving the bags in that location unattended is inconsistent with the Crown’s theory regarding the contents of the bags. Whilst the appearance of the backpack may have changed when the mother of the accused appears in the CCTV holding what seems to be the backpack after the fire, there is a degree of uncertainty about this. 294 Defence were critical of the lacuna in the evidence as to the backpack itself. The backpack was never tendered, there was no evidence about its physical characteristics, material from which it was made, its construction and the potential impact of the fire upon it. 295 In considering this strand of the circumstantial evidence as part of an assessment of all of the evidence, these issues need to be borne in mind. Good character evidence 296 The accused called three witnesses at a previous trial, Alison Rundle, Sharon Rathbone and Joanne Newman, to give evidence as to her good character and reputation. This evidence was tendered by consent as Exhibit D28. 297 Alison Randle has known the accused for ’30 plus’ years through community netball and she said the accused is well-liked, trustworthy and that she has a reputation for honesty. 298 Sharon Rathbone has known the accused for 30 years through netball and work. She said the accused has a reputation for being an honest person and helps people a lot. -- 67 of 73 -- [2025] SADC 35 66 299 Joanne Newman has known the accused for approximately 10 years. Ms Newman spoke of the accused’s reputation as a very honest, very loyal person. The accused was described as having an ‘upstanding reputation’. 300 The evidence of the accused’s good character is relevant for the following purposes: 301 First, when assessing the credibility or truthfulness of the accused’s evidence. A person of good character is generally considered to be less likely to lie or to give a false account of themselves when giving evidence, and as such, this is a consideration when deciding whether to accept the accused’s evidence. 302 Second, it is evidence that can be used in determining the likelihood that the accused committed the offence. This is because it is generally considered that a person of good character is less likely to commit a criminal offence and, in this way, evidence of good character should be taken into account when determining whether the prosecution has proved its case beyond reasonable doubt. 303 Naturally, a person of good character is capable of committing a criminal offence. This is to be borne in mind. Conclusion 304 Having regard to all of the evidence, I find the fire was deliberately lit. I accept the evidence of Mr Cox that the accused was burnt by a ventilation controlled fire that was already burning in the disabled toilet. I find that the accused was burnt when she opened the door of the toilet by reason of a backdraft event. 305 It remains necessary to consider the prosecution’s alternative contention that I can be satisfied that the accused was the arsonist nonetheless on the basis that the accused set the fire burning, with the resultant backdraft event. 306 In support of this hypothesis, the prosecution relied heavily on the DNA evidence, linking the accused to the bottles containing accelerant. As I have previously said, the prosecutor’s submission was that: ‘the accused’s DNA on the lids and the petrol is, of course, a fundamental aspect of the prosecution case’.450 307 Having identified the importance of this particular piece of circumstantial evidence, I make it clear that it is not an indispensable link in the chain of reasoning to establish an element of the offence.451 It is a piece of evidence to be considered with all of the evidence in deciding whether the offence has been proved beyond reasonable doubt. 308 Again, having regard to all of the evidence, in the particular circumstances of this case, I cannot exclude as a reasonable possibility that the presence of DNA 450 T689.13.15. 451 Shepherd v The Queen (1990) 170 CLR 573. -- 68 of 73 -- [2025] SADC 35 67 profiles on the lids of the bottles is attributable to innocent deposition through one of the mechanisms discussed in these Reasons for Verdict. 309 On the evidence of Sergeant Wynne, Brevet Sergeant Murphy, Commander Ruxton and Dr Taylor, there is a reasonable possibility that the DNA samples consistent with that of the accused were deposited via means other than the accused touching the lids of the two bottles. 310 Having regard to all of the evidence, I accept the evidence of Mr Cox as to his primary opinion as to the nature of the relevant fire. That is, that the fire which injured the accused was a backdraft event, which was burning before the accused opened the door of the toilet. In her actions opening the door, the accused sustained serious burn injuries. Having made these findings, the question then becomes has the prosecution, having regard to all of the evidence, excluded a reasonable possibility consistent with the innocence of the accused? Discussion – evidence of accused 311 In assessing whether the evidence of the accused is reasonably possibly true, I take into account the submissions of the prosecution and defence, together with all of the evidence. 312 There is nothing unusual or nefarious about the accused not immediately attending to the stated purpose of visiting the shopping centre, to purchase food. A careful reading of the evidence reveals that part of her reason for attending was to see if a parcel her husband was expecting had arrived, not that she was to collect a parcel that had already arrived. 313 However, the evidence from the accused regarding what bag she was carrying whilst walking in between the post office and her car is unclear at best and incorrect at worst. The accused described the bag as being an everyday shopping bag, and adopted the (leading) description given by counsel of a ‘Woolies’ or ‘Coles’ bag or ‘something like that’.452 314 The CCTV footage from the Australia Post shop (Exhibit P18) is far from clear, but neither of the bags being carried appear to match that description. 315 Further, as was emphasised by the prosecution, the accused’s description of the door to the toilet being ajar or ‘sticking out a little bit’ prior to her being burnt is at odds with the evidence of Mr Cox concerning a ventilation controlled fire burning within. For reasons above, I accept the evidence of Mr Cox on this topic and have found that a backdraft incident caused the injuries to the accused, casting additional doubt on the accuracy of the evidence of the accused. 316 Further, it is apparent the accused’s recollection generally about events of the day in question is unreliable. She was unable to recall what time she attended the 452 Defence counsel from the previous trial was not counsel at this trial. -- 69 of 73 -- [2025] SADC 35 68 shopping centre and has very little, if any, specific memory in the aftermath of being burnt. 317 The concession from the accused stating that she was “not sure what my memory is” as to her ability to recall events is telling. 318 In the circumstances, I have reservations about the reliability of the accused’s account. The discrepancies I have mentioned relate to important topics and adversely impact upon her reliability. The evidence of the accused was infected with unreliability. 319 The cross-examination of the accused at this trial was relatively brief (3½ pages of transcript) and was tendered as part of Exhibit P7. I did not have the opportunity to assess the accused’s demeanour and make my assessment based on the face of the record. 320 In assessing the credibility of the accused, I have regard to the entirety of her evidence in conjunction with the entirety of the evidence presented at trial, including the evidence of good character adduced on her behalf. The findings I have made above regarding the accused’s reliability are quite separate from an assessment of her credibility. I do not accept the failings in her reliability reflect adversely on her credibility. 321 During the course of cross examination, the accused’s evidence remained intact. There were no proven lies, nor did the answers given expose anything that would cause me to doubt the truthfulness of her denials as to the suggestion that she was the arsonist. 322 Whilst I have found that the evidence of the accused is infected with unreliability, the same does not apply to an assessment of her credibility. Noting that I did not have the opportunity to observe the demeanour of the accused whilst giving evidence and assessing her evidence on the face of the record, there is no reason for me to reject the accused’s denials of lighting the fire as not being reasonably possibly true. 323 Of course, the infirmities of the accused’s evidence in terms of its reliability adds nothing to the prosecution case and is not a makeweight. The burden remains fixed on the prosecution to prove its case beyond reasonable doubt. 324 During the prosecution address, reference was made to the evidence of Ms Magill, a member of the public who attended at the shopping centre on the day in question. Ms Magill gave evidence at a previous trial. That evidence was tendered in the current trial. The prosecutor referred to the evidence of Ms Magill that, in the immediate aftermath of the accused being burnt, being doused in water and then being attended to by paramedics for her injuries, the accused asked ‘where is my bag’. Whilst passing reference was made by the prosecutor on this topic during the closing address and similarly passing reference was made to the topic of consciousness of guilt, this submission was not further developed. As I -- 70 of 73 -- [2025] SADC 35 69 understand the final position, the Crown did not press reliance upon this aspect of the evidence as reflecting a consciousness of guilt. Given the state of the evidence before me and the fact that this submission was not further developed, I do not consider that this evidence is capable of evidencing a consciousness of guilt on the part of the accused.453 Findings 1. At some time prior to 5.15 pm on 23 December 2013, a fire was deliberately lit in the disabled toilet inside (the toilet) near one of the entrances to the Parafield Plaza Shopping Centre on Salisbury Highway (the shopping centre). 2. The fire was started with the assistance of an accelerant, namely petrol. 3. Six bottles containing petrol were placed in the roof cavity of the disabled toilet by the arsonist. 4. Before the fire, the accused was present at the shopping centre in the nearby Australia Post shop operated by her mother at the relevant time. 5. The accused attended at the Australia Post shop carrying a black backpack and another black bag. 6. The accused left the two bags on the front counter of the Australia Post shop before removing them to the back room of the outlet. 7. After the last customer had been served at the Australia Post shop the accused left the Australia Post shop with both bags, heading in the general direction of the toilet through the shopping centre. 8. Approximately 6 minutes later, an orange flash is observed on CCTV footage, noting that the CCTV footage does not cover the area of the toilet. 9. Approximately 30 seconds after the flash, the accused returns to the Australia Post shop. 10. Upon her return to the Australia Post shop, the accused had suffered burn injuries. 11. Approximately 12 seconds later, the mother of the accused returns to the Australia Post shop with what appears to be a backpack. 12. Fire cause investigators seized six bottles containing petrol from the roof cavity of the toilet. 453 Edwards v The Queen (1993) 178 CLR 193. -- 71 of 73 -- [2025] SADC 35 70 13. DNA testing revealed the presence of a DNA profile on two of the bottle lids for which there was extremely strong support for the proposition that the accused was a contributor. 14. Chemical analysis is unable to determine whether the presence of components of petrol on the clothing of the accused was caused by transfer of petrol in vapour or liquid form. 15. The fire incident responsible for the orange flash observed on the CCTV was caused by a backdraft incident. 16. The injuries to the accused were caused when she opened the door to the toilet, thereby precipitating the backdraft incident. 17. At the time the accused opened the door to the toilet, a deliberately lit fire had already been started in the toilet. 325 These findings are made having regard to the entirety of the evidence. 326 I am not satisfied, having regard to all of the evidence as to the primary contention of the prosecution, namely that the accused was injured as a consequence of being present inside the toilet at the time that she ignited petrol causing a flash fire. 327 Having made that finding, I am required to consider whether on all of the evidence, I am satisfied beyond reasonable doubt of the alternative hypothesis advanced by the prosecution, namely that the accused deliberately set a fire in the toilet at an earlier time and was subsequently injured as a consequence of opening the door, thereby precipitating the backdraft incident. 328 In this regard, the ultimate question remains whether the prosecution has proved beyond reasonable doubt that the accused was the arsonist, in particular whether the totality of the evidence excludes any reasonable hypothesis consistent with her innocence. 329 I will not fully repeat defence counsel’s submissions, which are set out above. In essence, it was submitted on behalf of the accused that having regard to all of the evidence, there was insufficient evidence to prove the prosecution case; that various of the inferences I was asked to draw could not be drawn given the deficiencies in that evidence (one such example being the real possibility of contamination of the DNA evidence). It was submitted that the absence of motive, together with the good character of the accused undermines the inferences sought to be drawn by the prosecution. Of course, I accept that the prosecution does not have to prove a motive. 330 Part of this global assessment necessarily includes the finding that, having regard to the whole of the evidence, I cannot exclude the denials of the accused as not being reasonably possibly true. -- 72 of 73 -- [2025] SADC 35 71 331 I have carefully reviewed the totality of the evidence and the submissions of the prosecution and defence, to consider whether I am able to exclude all reasonable hypothesis consistent with innocence and whether the matters urged upon me by defence counsel rest upon more than mere conjecture.454 332 While I am able to make some findings and draw the inferences I have set out above, having regard to all of the evidence, I am not satisfied that the prosecution has proved beyond reasonable doubt that the accused lit the fire. 333 I find the accused not guilty. 454 R v Baden-Clay (2016) 258 CLR 308 [47]. -- 73 of 73 --