Introduction

Many of the standard procedures used in investigating cases of homicide are either thwarted or, at least, significantly delayed when the body of the victim has been burned. Generally, the initial decision as to whether a homicide has occurred is based on an examination of the body. The type of wounds or injury to the body, the location of such wounds or trauma, the type of weapon apparently used, and the general appearance of the crime scene are primary to the determination of the likely cause of death and detecting whether or not a murder has taken place.

Murderers will sometimes burn a body in order to prevent or delay the identification of the body upon discovery. The body may also be burned to destroy evidence of the true cause of death or evidence of the crime scene. The most frequently used methods of attempting to prevent identification or to destroy evidence is to set fire to the house, building or vehicle containing the body or to pour some type of inflammable liquid on the victim and ignite the body (Tedeschi, Eckert and Tedeschi, 1977). When confronted with a burned body, the key questions for the investigator include: whether the burns were the cause of death, were they produced before or after death, and are there other injuries to the victim?

As Polson (1965) pointed out, determination of when the burns were received, before or after death, is critically important. If the burns were ante-mortem, before death, then it is important to determine if the burns were the cause of death. On the other hand, if the burns were post-mortem, it is possible that the victim’s death occurred by violence and the fire was an attempt to conceal the crime or destroy evidence.

Determination of cause of death and time of fire injury to the victim must be left to the medical examiner (Kessler and Weston, 1972; Fisher, 1952). In the past, some arson/homicide investigators tended to rely on their own judgment, using simplistic characteristics of burned bodies as guidelines. One of those characteristics was the "pugilistic attitude" of a burned body, caused by the effects of extreme heat on the muscles of the body (Geberth, 1990). A body exposed to sufficient fire will assume the pugilistic attitude irrespective of life or death at the time of exposure to the fire (O’Connor, 1987). The pugilistic attitude is not always present, however, even if the body has been exposed to ample fire to normally result in the attitude. This may occur if the body was in rigor mortis prior to the fire (O’Connor, 1987). In one of the cases included in this study, the murderer returned to the scene approximately 24 hours after the murder and set the fire that destroyed the victim’s body and residence. In this case, only a limited pugilistic attitude was noted.

Another common belief is that blisters will only form on the skin if the victim was alive at the time of the fire. This belief is also not correct. As Spitz and Fisher (1973) point out, even microscopic examination may not be able to determine whether burn blisters on the skin occurred shortly before death or whether they occurred after death. Most persons who die in a conflagration are killed by asphyxiant gases before any burning of the body occurs (Dutra, 1949; Fisher, 1952; Geberth, 1990). Carbon monoxide poisoning is the most common poisoning due to asphyxiant gases (Courville, 1964).

When arson is involved in a homicide, regardless of whether the arson caused death or took place after death, the investigation is made much more difficult (Geberth, 1990). Although no two crimes are exactly alike, there are certain similarities and differences that are shared (Ressler, Burgess, and Douglas, 1988). This study was designed to provide arson-homicide investigators with information that may help to differentiate and identify common characteristics and significant differences.