COHb Levels in Fire Victims and Origin Analysis An ATF Case Study

Transcription

1 COHb Levels in Fire Victims and Origin Analysis An ATF Case Study Derek J. Hill Special Agent/Certified Fire Investigator (CFI) Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF)

2 ACKNOWLEDGEMENTS: Technical and Editorial Contributions From: Paul Claflin, Special Agent/CFI ATF Michael Marquardt, Special Agent/CFI ATF James Olson, Special Agent/CFI ATF Daniel Heenan, Special Agent/CFI ATF James Lord, Fire Research Engineer ATF John Golder, Special Agent/CFI -- ATF 1

3 Abstract The determination of the origin and cause of a fire is a difficult endeavor that requires fire investigators to follow the Scientific Method to reach testable hypotheses as to how a fire started. As part of this process, fire investigators must consider all information available to them in analyzing their developed hypotheses. In recent years there has been an argument put forward in the fire investigation community that a fatal fire victim s carboxyhemoglobin (COHb) concentration is an important factor to consider when determining the origin of a fire. This argument has been argued in Indiana and Texas courts and was recognized by those courts to be newly discovered evidence by the court. Although the consideration of post-mortem data from victims is important in any death investigation, the use of COHb concentrations in identifying the origin of a fire is a risky endeavor with today s level of scientific understanding in the COHb arena. Data obtained and compiled from a survey conducted by Certified Fire Investigators (CFI) with the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) reveals significant potential pitfalls with allowing the COHb concentrations of fire victims to significantly influence the hypothesis of the fire investigator as to the area of origin, and the correlation it has with the origin of a fire. Introduction Laramie County Murder-Suicide On February 3, 2012, a fire occurred at a mobile home in Laramie County, Wyoming. During the search of the building, a 35 year old female and her 11 year old daughter were found deceased inside the residence. The mother was located in the living room of the residence, lying on the floor between the couch and a coffee table. The daughter was found in the adjacent bedroom. A CFI with ATF was contacted by local law enforcement to assist in the fire scene examination. The residence was located in a mobile home park and the fire was discovered at approximately 4:45 AM by a passerby who observed fire venting from the north door of the building. When firefighters arrived, smoke and fire were venting from the living room window on the north side of the building adjacent to the north door. Firefighters gained entry into the building by forcing open the south door. Firefighters searched the residence and recovered the juvenile female victim, whom they removed from the building. The adult female victim was located in the living room but was not immediately removed as it was apparent she was deceased. After a systematic fire scene examination, fire investigators determined that gasoline was distributed to three separate areas; which included the living room, first bedroom and second bedroom. The incendiary fire was the result of the application of an open flame ignition source to the vapors. In the living room, where the adult female was discovered, there was an irregular burn pattern and associated fire damage on the floor surrounding the victim. An empty two-gallon gasoline container was located on the living room floor near the victim (Figure 1, Figure 2). On the floor, near the victim s body, was a barbecue lighter. On the coffee table, near the victim s body, were two additional barbecue lighters and a book of matches. Two samples of carpet and carpet padding were collected in the living room near the victim s body. Laboratory analysis confirmed that gasoline was present in each of these samples. 2

4 Figure 1 Source: ATF SA/CFI Paul Claflin Figure 2 Source: ATF SA/CFI Paul Claflin The kitchen was located adjacent to the living room and an empty gasoline container was located on the kitchen floor. In the kitchen trash can were two gasoline container nozzles, one gasoline container cap, and two gasoline container spouts. The oven door was open and the oven controls were set to broil and timed bake, pre-heat. The four burner controls of the range were set on high. The first bedroom, adjacent to the living room, was the second area of origin and the bedroom where the juvenile victim was located. There was an irregular burn pattern and associated fire damage that began in the doorway of the bedroom and continued to the foot of the bed, where the juvenile victim was discovered. An empty gasoline container was found within the identified area of origin (Figure 3). A sample of carpet and carpet padding was collected from the foot of the bed. Laboratory analysis confirmed that gasoline was present in this sample. 3

5 Figure 3 Source: ATF SA/CFI Paul Claflin The second bedroom was located east of the first bedroom, down the hallway from the living room. There was an irregular burn pattern and associated fire damage on the south side of the bed. Another empty gasoline container was found on the floor. A sample of carpet and carpet padding was collected from the foot of the bed. Laboratory analysis confirmed that gasoline was present in this sample. Fire investigators obtained video surveillance footage from a gasoline station that depicted the adult female, filling a gasoline container prior to the fire. Fire investigators concluded that the adult female, who was reportedly distraught prior to the incident, started the fire in three separate areas of the residence in what was determined to be a murder-suicide. Decatur County, IN Fire (Bunch Case) In 1995, a fire occurred at a residence in Decatur County, Indiana in which a 4 year old child died in the fire. An autopsy conducted on the child determined the child died of smoke inhalation. The child s carboxyhemoglobin (COHb) level was determined to be 80% and the cause of death was listed as smoke inhalation. After an investigation, the mother of the child was charged with and convicted of arson and murder. In 2006, a new trial was requested in part based upon a claim of newly-discovered evidence. The argument made by defense experts in the case was that COHb levels of fire victims needs to be considered when determining the origin and cause of a fire and that in this case the COHb level of the fire victim was not considered. The defense expert stated that a fire, which began in an open space (the victim s bedroom), cannot produce enough carbon monoxide to have raised the victim s COHb level to 80% in less than an hour, before which time he would have died as the result of thermal injury. The postconviction court denied this argument in part based on the fact the defense expert did not present any evidence of scientific principles or studies that substantiated or correlated the carbon monoxide level of a person killed in a fire to the place of origin of that fire. Nor were any such studies admitted into evidence. The post-conviction court was overturned by the Indiana Court of Appeals and a new trial was ordered in part based on fire victim toxicology being successfully argued as newly-discovered evidence. (Robb, 2012) Because of the similarities between the Decatur County, IN fire and the Laramie County murder-suicide, the autopsy results from the Laramie County fire were further examined, specifically looking at the COHb levels of each victim. The fire investigator anticipated to find low COHb levels in the mother and 4

6 daughter, who were located directly adjacent to burning gasoline pools, and who, based upon the suggested theory, presumably would have succumbed to thermal injuries prior to breathing enough carbon monoxide to have elevated COHb levels. The pathologist determined that the juvenile victim died of a combination of smoke inhalation and thermal injuries and had a COHb level of 67.6%. The pathologist determined that the adult female died of smoke inhalation and thermal injuries and had a COHb level of 72.8%. This data appears to contradict the theory put forth by defense experts in the Bunch case. Fire Deaths During , U.S. home structure fires killed an estimated average of 2,570 people and caused an average of 13,210 reported civilian injuries per year. Overall, 51% of those killed and 60% of those injured were in the area of origin at the time the incident began. (Ahrens, 2014) Direct flame, heat, smoke, and soot exposure are examples of ways in which a fire can result in a fatality. Some of the major lethal agents in fires are heat, the production of smoke and the inhalation of smoke and other toxic gases. The survivability in this environment is referred to as tenability. Based on the results of large-scale fire tests, even in a worst-case scenario of a rapidly growing flaming fire, it is anticipated in many cases there will be a period of time before which conditions become untenable. Based on a knowledge of the toxicity of fire products, it would, therefore, be anticipated that a conscious, healthy, mobile individual would in many cases have an opportunity to escape from such situations. Under the same scenario, or under one such as a smoldering or a relatively slowly developing fire, a sleeping or otherwise incapacitated victim may be overcome by the by-products of the fire before attempting an escape. (SFPE Handbook of Fire Protection Engineering, 2008, pp ) Fires in closed compartments, such as bedrooms, present a hazardous situation, wherein a flaming fire quickly consumes the available oxygen and the oxygen concentration falls after a minute or so of burning. The combustion thus becomes inefficient, producing a dense smoke rich in carbon monoxide and other toxic products. These, together with the lowered oxygen concentration in a room, can rapidly produce a lethal atmosphere and low to zero tenability. (SFPE Handbook of Fire Protection Engineering, 2008, pp ) Additionally, the SFPE Handbook states that in general, although fire and heat may eventually kill victims, this is usually preceded by dense, highly toxic smoke that can spread rapidly throughout a space or a building, which is usually responsible for the initial incapacitation of occupants, as well as being the cause of many deaths. Carbon Monoxide (CO) and Hydrogen Cyanide (HCN) Two major asphyxiate gases in fires are carbon monoxide (CO) and hydrogen cyanide (HCN). Carbon monoxide is produced in virtually all fires by the incomplete combustion of any carbon-containing fuel. The rate of carbon monoxide production in fires, especially those within compartments, is dependent on several factors including whether the fire is well-ventilated or under ventilated. Carbon monoxide acts as a depressant on the central nervous system. When it is inhaled, CO binds with hemoglobin in blood, creating carboxyhemoglobin (COHb). The affinity of carbon monoxide for hemoglobin is approximately times more that than the affinity of oxygen for hemoglobin. Therefore, the blood can accumulate dangerous levels of COHb from even low CO concentrations. (NFPA Guide for Fire & Explosion Investigations, 2014 Edition) Although a 50% COHb level is widely considered to be the benchmark for a fatal COHb concentration, 5

7 COHb levels considerably lower than 50% can result in death. COHb levels of 30% to 40% is believed to be the level at which incapacitation occurs. (DeHaan & Icove, 2012, p. 637) In the case of Ed Graf, which is discussed further later, defense experts successfully argued that the use of COHb concentrations in determining the area of origin was in fact newly discovered evidence. In the Graf case, defense experts argued that had the victims of the fire been exposed to an ignitable liquid, they would have died as a result of thermal injuries prior to obtaining a lethal concentration of carbon monoxide. Defense experts in the Graf case further stated that a COHb level of 40% was considered to be a fatal level. Because of this successful appellate argument in the Graf case and for the purposes of this analysis, the COHb level of 40% was used as the fatal level. (Carpenter, 2011) COHb is relatively stable and because of this, it can be measured in the blood of fire victims, long after death. Hydrogen cyanide (HCN), in addition to carbon monoxide is another important toxicant that is produced in fires. HCN is produced during the combustion of nitrogen based materials such as wool, nylon, and plastics, which are commonly found in household furniture and interior finishes. When HCN is inhaled during respiration, it is rapidly absorbed into the bloodstream. The diffusion capabilities of HCN are more significant than those of CO, which explains its rapid lethal effects. While carbon monoxide affects the binding of oxygen to hemoglobin, HCN effects the utilization of oxygen. These effects result in paralysis of the respiratory center in the brain which can lead to death. Unlike COHb, HCN does not show the same stability in blood and will naturally dissipate even in fire fatalities, which results in misleading results unless the blood sample is collected and analyzed in close proximity to the time of death. The dynamics of any given fire influence the production of CO and HCN, arising from the thermal disintegration of materials present at the site. Furthermore, HCN production and inhalation in fires appears to play an important, yet not thoroughly understood role in fire fatalities but HCN levels are rarely requested as part of a post-mortem examination. The unknown role that a combination of HCN and CO play in a fire fatality along with the different dynamics of individual fires poses a real problem for fire investigators attempting to utilize victim blood toxicity levels in support of their origin and cause determination. The Role of NFPA 921 The 2014 Edition of the NFPA 921, Guide for Fire and Explosion Investigations was released in December Chapter 25 Fire and Explosion Deaths and Injuries contains several sections related to fire victims and their COHb concentrations. The 2014 Edition of NFPA 921, Section was added and deals with the correlation between COHb levels in fire victims and their relation to the area of origin for the fire. The 2008 and 2011 editions also contained language regarding this issue and proposals have been made to make the language much stronger but thus far have been rejected by vote of the committee. Court Arguments The use of victim toxicological data and its relationship to the origin and cause of a fire became an argument that would soon be used in appellate courts in an attempt to overturn criminal convictions based on the theory that this data was newly discovered evidence in the form of advances in the field of fire science. The first argument based on this data appears to have taken place in the case previously mentioned out of Decatur County, Indiana. A post-conviction court heard testimony from a defense expert that testified the fire that killed the child in Indiana had to have occurred in a concealed space to produce the COHb levels found in the child. The expert contended that if the fire had occurred the way the government contended, the child would have died from thermal injuries prior to attaining a COHb level of 80%. The post-conviction court denied the claim of newly discovered evidence in part based 6

8 on the fact that there were no studies admitted into evidence that supported the theory given by the defense expert. Ultimately, an Indiana Court of Appeals overturned the conviction of the child s mother and she was released from incarceration. The author is aware that other issues have arisen in the case that played a part in the dismissal of the case. The purpose of this paper is not to challenge the guilt or innocence of the mother charged in the case but rather to question the scientific validity of placing too much emphasis on victim COHb concentrations in determining the origin of a fire. Following the case out of Indiana, additional arguments on the same topic were put forth in the criminal courts in the State of Texas vs. Ed Graf and the State of Alabama vs. Christie Scott. In each of these cases, an argument was made that high COHb concentrations were not indicative of the victim being located in the area of origin and in the case of Graf, the use of an accelerant was also not indicative of a high COHb concentration. In other words, the victim toxicity levels were being used to argue that the fire investigator identified the wrong area of fire origin. In the Graf case, it was further argued that had the fire involved a liquid such as gasoline, the victims would have died from thermal injuries prior to attaining lethal levels of COHb. Each of the cases is briefly described below and although this paper focuses on the use of toxicological data, other issues also factored into each respective court s decisions. State of Texas vs. Ed Graf On August 26, 1986 a fire occurred in Waco, Texas at the residence of Ed Graf. Firefighters arrived and found a shed on the Graf's property fully involved with fire. After knocking down the fire, Firefighters learned that Graf's two step-sons were missing. The body of Joby Graf (9 years of age) was found near the shed's two front doors while the body of Jason Graf (8 years of age) was found in a rear corner of the shed. An autopsy revealed that Joby Graf's carbon monoxide level was 86% at the time of his death and Jason Graf's carbon monoxide level was determined to be 76%. State fire investigators determined the fire originated in the front, left corner of the shed and that some type of accelerant was used to enhance the fire. Additionally, the state's expert stated the door to the shed was closed at the time of the fire. Based on this and other factors in the case, Ed Graf was charged with murder, convicted and sentenced to life in prison. Ed Graf appealed his conviction and in 2013 the Texas Court of Criminal Appeals ordered a new trial for Graf. Part of Graf's argument in the appellate court hinged on the high carbon monoxide levels found in both Joby and Jason Graf. Defense experts argued that the fire could not have involved gasoline as the boys would have died from thermal injuries before their carbon monoxide levels got as high as they did. Experts argued that incapacitation occurs with a carbon monoxide level of 30% - 40% and lethal levels range from 40% - 80%. A new trial was ordered for Ed Graf and on October 6, 2014 the retrial of Ed Graf began in Waco, Texas. During the retrial, the arguments were once again made that due to the boys high carbon monoxide levels, the fire was not an act of arson but was in fact the result of boys playing with fire and an accidental fire was what caused the boys deaths. The argument was that a fire started in this manner would create the toxic conditions that led to the boys attaining the high COHb levels they had in their system, while a fire involving ignitable liquids would result in death due to thermal injuries. Another explanation given for the boys high COHb levels was that the fire occurred in a concealed area within the shed. This concealed area or compartment within a compartment purportedly allowed for the fire to produce the high levels of carbon monoxide that would have produced the lethal levels found in the boys. There was also disagreement on whether the shed doors were open or closed at the time of the fire. After a two week trial that ended on October 20, 2014 the jury began their deliberations. Prior to a verdict being reached, on October 21, 2014, Ed Graf pled guilty to killing his two step-sons. As part of 7

9 the plea deal, Graf was given credit for time served and shortly after the trial concluded, Graf was released from prison. State of Alabama vs. Christie Scott In the early morning hours of August 16, 2008, a fire occurred at a residence located in Russellville, Alabama. Upon arrival, emergency responders were contacted by Christie Scott, who was screaming that her child was still in the house. Scott informed the initial police officer that arrived on scene which bedroom her missing son was in and that the bedroom was fully involved with flames. The officer attempted to enter through the front door but was repelled by the heat and flames emitting from the structure. The officer then ran to the rear of the structure and attempted entry, but again was repelled by the heat and flames. The officer then remained outside and awaited the arrival of the fire department. After the fire was suppressed, the body of Mason Scott was recovered from his bedroom. More specifically, Mason Scott s body was recovered in an area between the bed and the closet. Mason Scott normally shared this bedroom with his younger brother but on the night of the fire, the younger brother was sleeping with Christie Scott in her bed. A pathologist with the Alabama Department of Forensic Services conducted an autopsy on Mason Scott and determined he died from smoke inhalation and thermal burns. Mason Scott s carboxyhemoglobin level was determined to be 90%. A Certified Fire Investigator (CFI) with the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) was contacted and was asked to assist in the origin and cause determination of the fire. A systematic fire scene examination took place involving ATF, the Alabama State Fire Marshal s Office, the Russellville Police Department and the Russellville Fire Department. An electrical engineer was also brought in to examine the electrical system. After examining the scene, investigators determined the fire was intentionally set by igniting a bed located in the bedroom where Mason Scott was located. Additional information gleaned during the investigation led to the arrest of Christie Scott. Scott was charged with capital murder. During Scott s trial, the defense presented arguments that the fire was accidental and started inside of a television cabinet located in the children s bedroom. This opinion was based in part, on the high COHb level of Mason Scott. The defense further argued that a fire started on the child s bed would not produce the high levels of carbon monoxide found in the victim. However, it was argued that a fire originating in the television cabinet would produce the extremely high levels of carbon monoxide found in the blood of the victim. Scott was convicted on all counts and the jury split 7-5 in determining whether Scott should receive the death penalty. Because of the split, Scott was to receive life in prison, however the presiding judge sentenced Scott to death. ATF Study In 2014, the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) conducted an anecdotal or historical review involving the collection of data from fatal fires where ATF Certified Fire Investigator's (CFI) had conducted a fire scene examination. The purpose of the study was to evaluate whether or not there might be any meaningful correlation between the victim s recovery location, the fire victim s COHb level and the area of origin of the fire. ATF CFI s were asked to participate in a survey that asked specific questions about fatal fire scenes they had worked. The following categories were identified in the survey: Date; Case Number; Gender; Victim DOB; COHb Level; Room of Origin; Floor of Origin; Victim Location; Victim Floor Location; Cause; Ignitable Liquid Involved; and Other Factors. It was further requested that only origin and cause (O & C) reports prepared by ATF CFI s be submitted. This was done so the author could review the various reports and identify each of the cases by their unique ATF case identifier. 8

10 Responses were received and prior to identifying any numerical data, cases were examined and evaluated and as a result, some were excluded because they did not meet the criteria that had been established. Examples of the established criteria that would preclude a case from being used in the study included fire investigations in which an ATF CFI did not draft or participate in the drafting of an origin and cause report, cases where evidence established the victim or victims were deceased prior to the fire and fatalities that were a result of motor vehicle fires. Upon reviewing the cases submitted, 53 cases were identified as fitting the criteria. In a few instances, a judicial disposition was located. In some cases, the COHb level was listed in the autopsy finding only as greater than or less than fifty percent (i.e. - >50% was given a COHb level of 50%). Also in some cases, the ages of the victim was listed as less than one year. For the purpose of this study, in these instances, the value used for <1 was given an age of 1 year. Additionally in some cases where there were multiple victims, who were located both inside and outside the determined area of origin for the same incident. Fire Victims The 53 fire cases that were reviewed resulted in 85 fire fatalities. The youngest victim in the study was 3 months old while the oldest victim was 84 years old. The chart below provides a view of the ages of victims and the average COHb for the age group identified (Figure 5). Figure 5 - Victim Breakdown Age of Victims (Yrs) Number of Victims Avg. COHb (%) 5 and under to to to to to to to and over Total 85 Source: ATF Fatal Fire Victim Survey Of the 85 victims that were identified, 28 of the victims were identified as being in the area of origin while 57 of the victims were identified as being outside the area of origin based upon the evidence established by the original fire scene investigation. Upon reviewing the COHb levels for all of the victims, the average COHb was determined to be 53.8%. A further break down yielded an average COHb level of 46.1% for victims located in the area of origin. An average COHb of 57.9% was determined for victims located outside the area of origin. The COHb levels of victims, where an ignitable liquid was confirmed via laboratory analysis, was also examined. The average COHb level for these victims was determined to be 43.9% (Figure 6). 9

11 Figure 6 - Average COHb Levels Average COHb Levels COHb concentrations % 90.00% 80.00% 70.00% 60.00% 50.00% 40.00% 30.00% 20.00% 10.00% 0.00% 53.8% Avg COhb of all Victims (85 victims) 46.1% Victims in Area of Origin (28 victims) 57.9% Victims Outside the Area of Origin (57 victims) 43.9% COhb Level of Victims Located in the Area of Origin Where Ignitable Liquids Were Present (20 victims) Source: ATF Fatal Fire Victim Survey Fires with Victim in Area of Origin In 15 of the 53 fires examined, victims were identified as being in the area of origin. These 15 fires accounted for 28 of the fire related fatality victims. The average COHb for these victims was 46.1%. The highest documented COHb level was 88% for a victim located in the area of origin while <5% was the lowest documented percentage (Figure 7). Based on the lowest documented COHb percentage, it is unknown if the victim was alive at the time of the fire or was deceased prior to the fire beginning. Figure 7 - COHb Levels for All Victims Located in the Area of Origin COHB 100.0% 80.0% 60.0% 40.0% 20.0% 0.0% COHB levels for all victims located in the area of origin Source: ATF Fatal Fire Victim Survey Victim 1 Victim 2 Victim 3 Victim 4 Victim 5 Victim 6 In some of the fires, multiple victims were discovered in the hypothesized area of origin and although they were found in the same area, their recorded COHb levels varied significantly. In some cases different victims found within the same location, and reasonably believed to have suffered very similar fire exposures, were found to have varied levels of COHb toxicity ranging between what is considered lethal and less than lethal levels. The available scientific research suggests these variances can be 10

12 attributed in part to each individual s unique biology. The individual victim s age, mass, medical health and history, medication use, illegal drug use, alcohol intake, are all considered factors that may influence the different COHb levels from one person to the next when exposed to the same conditions. Fires with Victim in the Area of Origin with a Fatal Level of COHb 10 fires were identified in which a total of 16 victims were located in the identified area of origin in which each of the victims COHb levels that was identified to be >40%. The 16 victims in these fires had an average COHb of 64.2%. The highest documented COHb level was 88% while the lowest COHb level was 43.6% (Figure 8). Figure 8 - Fires with Victims Located in the Area of Origin with a Fatal COHb Level FIRES WITH VICTIMS LOCATED IN THE AREA OF ORIGIN WITH A FATAL COHB LEVEL Victim 1 Victim 2 72% 72% 62% 45% 73% 76% 50% 88% 63% 69% 58% 60% 44% 68% 84% 44% Victim 1 Source: ATF Fatal Fire Victim Survey Fires with Victim in the Area of Origin with a Borderline Level of COHb Three (3) fires involved victims located in the area of origin with a COHb level slightly below the 40% threshold utilized in this study. The 3 victims in these fires had COHb levels of 38%, 39% and 38%. Fires with Victim in the Area of Origin with a Low Level of COHb Four (4) fires involved 9 victims who were located in the identified area of origin with COHb levels less than 30%. The average COHb level for the 9 victims identified in these fires was 12.8%. The highest COHb level was 27% and the lowest documented COHb level was <5%. Fires Involving an Ignitable Liquid As stated earlier, arguments have been made that if a fire victim is found to have a high COHb level, that particular victim would not have been located in the area of origin and thus the area of origin needs to be reexamined as it is potentially wrongly identified. Taking it one step further, the argument has now included that if a fire victim is exposed to a fire involving an ignitable liquid, they would succumb to thermal injuries prior to obtaining a lethal level of COHb. 11

13 Because of this particular argument, the analysis was particularly interested in the levels of COHb that were documented in cases in which an ignitable liquid was identified as verified by a credible forensic laboratory analysis or was acknowledged during court proceedings. This particular question was posed to ATF CFI s as part of the survey. Of the 53 fires that were examined, 8 of them involved the presence or use of an ignitable liquid. These 8 fires accounted for 20 of the fire related deaths. The overall average COHb level for these 20 victims was 43.9%. The highest documented COHb was 86.4% while the lowest level was <5% (Figure 9). Figure 9 Fires Involving an Ignitable Liquid Fires Involving an Ignitable Liquid and the Victim was Located in the Area of Origin COHB 100.0% 90.0% 80.0% 70.0% 60.0% 50.0% 40.0% 30.0% 20.0% 10.0% 0.0% (Cardile) Source: ATF Fatal Fire Victim Survey Case Examples Victim 1 Victim2 Victim 3 Victim 4 Victim 5 Victim 6 On September 19, 2011 at approximately 2:00 p.m., a 57 year old male victim spilled gasoline on a work bench and on himself while working within a 10 x 18 wood framed maintenance shed. The gasoline vapors ignited, resulting in a small explosion and fire, of which he was standing in the origin. A witness who heard and observed the event from a short distance away described seeing the victim standing and screaming for a brief period, while engulfed in flames from approximately the knees up. The victim fell backward and continued burning and died. The victim s body sustained severe burns and the maintenance shed sustained heavy fire damage. The scene was examined and samples were taken from around the victim s body as well as samples of the victim s clothing. A credible forensic laboratory determined the samples collected from around the victim s body as well as the clothing samples collected from the victim tested positive for the presence of gasoline. Multiple gasoline containers were located inside of the maintenance shed. An autopsy was conducted and the victim s COHb concentration was determined to be 60%. A butane lighter was located melted/imbedded in the side of the remains of a red plastic gasoline container near the victim. It could not be determined if the lighter was the ignition source or what the victim was doing with the lighter as he was not a cigarette smoker per his widow. 12

14 Figure 10 Source: ATF SA/CFI Michael Marquardt Figure 10 depicts the shed pre-dig with the victim in the center of the debris on the floor of the shed. The victim s torso is located to the right of the metal trash cans; the white object just below the torso area is the remains of the victim s right leg. Figure 11 and Figure 12 depict the shed after the scene examination. Figure 11 Source: ATF SA/CFI Michael Marquardt 13

15 Figure 12 Source: ATF SA/CFI Michael Marquardt The Use of Inconsistent Data The book Scientific Protocols for Fire Investigation cites seven general categories of fire investigation errors. One of the categories identified was ignoring inconsistent data. The author stated Ignoring inconsistent data is one of the most insidious errors and a classic symptom of a closed mind. Inconsistent data should be apparent to anyone who follows the scientific method and performs hypothesis testing using deductive reasoning. (Lentini, 2006) Analyzing the results of the survey conducted of ATF related fire fatality cases, it is apparent that attempting to directly correlate a victim s COHb concentration with the area or origin and drawing definitive conclusions is speculative at best based on the current scientific understanding. At the very least, one could argue that a fire investigator espousing this theory is ignoring significant inconsistent data as we understand it today. The study clearly suggests that victims located in the identified area of origin, both with and without an ignitable liquid present, can in fact attain a lethal COHb concentration prior to succumbing to thermal injuries. Closing Comments Fire investigation is a forensic science that continues to evolve and change through scientific based research and training. Whether it is a public or private investigator, fire investigators are required to remain current with the latest training and developments. Fire investigators have a duty to examine, evaluate, and debate the merits of various theories being put forth within the fire investigation field and especially those being argued before various courts. A brief examination of the history of fire investigation reveals myths and legends are easily spawned and spread without scientific basis. Fire investigators need not look too deep to past cases where indicators such as the crazing of glass, spalling, alligatoring and other non-scientific supported indicators were used to confirm the use of an ignitable liquid or how hot a fire was burning at the time. These indicators have been debunked and are now paraded within the fire investigation community and the media as junk science. Reviewing the data provided regarding the correlation between victim s COHb concentrations and the 14

16 area of origin, one could argue that some of the data in the survey supports the theory that victims in the area of origin could not attain a lethal level of COHb due to thermal injuries. However, additional data obtained in this survey clearly contradicts such a finding. Specifically analyzing even a small portion of the data reveals that out of the 53 cases, 10 of the cases had victims in the area of origin with fatal COHb concentrations. 15

17 References Ahrens, M. (2014). Characteristics of Home Fire Victims. Quincy, MA: NFPA. Carpenter, D. J. (2011). Analysis of the Fire at the Graf Residence. DeHaan, J. D., & Icove, D. J. (2012). Kirk's Fire Investigation (Seventh Addition). Pearson. Icove, D. J., & DeHaan, J. D. (2009). Forensic Fire Scene Reconstruction (Second Addition). Lentini, J. J. (2006). Scientific Protocols for Fire Investigation. Taylor & Francis. NFPA Guide for Fire & Explosion Investigations. (2014 Edition). NFPA. Robb, C. J. (2012). Indiana Supreme Court, Court of Appeals. SFPE Handbook of Fire Protection Engineering. (2008). National Fire Protection Association (NFPA). 16