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Penetrating Trauma Close-Range Firearm Wounds Summary Firearm Deaths Are Most Commonly Self-Inflicted

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Penetrating Trauma Close-Range Firearm Wounds Summary Firearm Deaths Are Most Commonly Self-Inflicted Chapter 6 Penetrating Trauma Close-Range Firearm Wounds Summary Firearm deaths are most commonly self-inflicted. The determination of suicide is supported not only by the presence of a close-range wound but also by the scene and historical information. A com- plete external examination of the victim may also reveal evidence of self-intent on the hand(s), i.e., blood spatter and soot deposition. The head is the most common site for self-inflicted wounds. Cranial injuries can have unique features (e.g., ricochet). Certain factors complicate the assessment of close-range firearm injuries. Medical procedures and interposed clothing can alter wound appear- ance. Unusually located or multiple wounds arouse suspicion of homicide. Examination of a wound track determines the cause of death. In the case of multiple wound tracks, relative lethality and inca- pacitation need to be assessed in the determination of manner of death. Key Words: Wounds; gunshot; suicide; head injuries; penetrating. 1. DEMOGRAPHY The incidence of firearms-related deaths per 100,000 population was 0.14 per 100,000 in England and Wales in 2001 (suicide, 65%; homicide, 7%; undetermined or accidental, 28%), 2.6 in Canada in 2002 (suicide, 80%; homicide, 15%; undetermined or accidental, 5%), and 10.2 in the United States in 2001 (suicide, 67%; homicide, 27%; undetermined or accidental, 6% [1–3]). The use of a firearm to commit suicide depends on the availability of firearms (4–15). In the United States, suicide by firearm is the most common method of commit- ting suicide (9,16). For example, studies in various southern states show use of a firearm in 65 to 87% of suicides (17–20). Various European studies have shown that about 4 to 8% of suicides are committed by firearms (21–23). In US jurisdictions, firearms are used for all victims of murder–suicide in 75 to 96% of cases (24–29). Self-inflicted firearm injuries occur in adults of all ages (21). Various studies have shown that the mean or median age of adult suicides is higher than that of homicide vic- tims (18,30–37). For example, a New Mexico/South Carolina study of self-inflicted head From: Forensic Science and Medicine: Forensic Pathology of Trauma: Common Problems for the Pathologist By: M. J. Shkrum and D. A. Ramsay © Humana Press Inc., Totowa, NJ 295 296 The Forensic Pathology of Trauma wounds showed that the average age of suicide victims was 39.2 yr, compared with 33.7 yr for murder victims (30). A similar older age distribution is seen in perpetrators of murder–suicide, but if children are murdered, then the average age of the murderer, i.e., the suicide victim, decreases (e.g., in an Australian study, the average was 31 yr [12,28,29,38]). Gunshot wounds involving children can be of any manner (39,40). Accidents occur when children play with guns (39,41–44). Adolescents may “fool around” with guns, and alcohol intoxication may be a factor in these cases (42). Availability and accessibility to firearms, their resemblance to toy guns, and gun malfunction are factors in accidental firearm deaths (4,41,43). Self-inflicted accidental wounds occur (41). The most common wound site is the head (41,44). Suicidal gunshot wounds are unusual in children and adolescents. A review of 45 shooting deaths of children under 10 yr during a 9-yr period in Cook County, IL, revealed no suicides (45). The minimum age in other studies of self-inflicted firearm injures is relatively consistent: South Carolina, 12 yr; South Carolina–New Mexico, 14 yr; Texas, 11 yr; New York City, 13 yr (6,18,30,32). The firearm can be borrowed or stolen (12,17). Self-inflicted gunshot wounds show a male predominance, although women are fre- quent victims in some jurisdictions (9,14,23,33–36,46–49). In foreign countries, fewer than 10% of firearm suicides involve women, whereas in various American jurisdictions the fre- quency varies from about 5% to 17% (6,18,21,32,37,50,51). The reasons for this sex dif- ference include less access by women to firearms in some countries and the knowledge that a firearm injury is potentially disfiguring, particularly when the entry site is the head (21). Female victims predominate in murder–suicides (12,52). In various US and inter- national studies, there is a male perpetrator, i.e., suicide victim, in 85 to 100% of cases depending on the age group (12,24–26,28,29,52). If children are murdered, then the per- centage of female perpetrators increases (53). 2. SCENE Whether the investigation involves a single-victim suicide or multiple fatalities in a murder–suicide, the location chosen is usually familiar. In most cases, the deaths occur at home or its vicinity (17,21,24,26,28,34,35,37,46,48–50,54,55). Often the door is secured from the inside (e.g., locked, wedged by chair), which assists the investiga- tion when the circumstances are unusual (e.g., multiple wounds [37,56–60]). Unusual locations (e.g., motor vehicle) have been described (55,61,62). 3. TYPE OF FIREARM There is a handgun predominance in American and most international studies (20–22,30,32,63–66). In the United States, this reflects the possession of firearms for protection. For example, in one jurisdiction in Texas, the following distribution of firearms was seen in suicide cases (32): Handguna Rifle Shotgunb Male 76.1% 13.7% 10.2% Female 87.4% 6.7% 6% a38 special most common. b12-gauge in more than half of cases. In other regions (Canada, England, Scandinavia, Australia), there is a predomi- nance of long gun use (rifles and shotguns) because of restrictions on firearm possession Chapter 6/Penetrating Trauma 297 (23,34–37,46–49). Lower caliber weapons (handguns and rifles) are usual in multishot suicides, but higher caliber handguns and shotguns are used (67). The following is a list of some unusual firearms or projectiles that have been used to cause self-inflicted gunshot wounds: • Handguns using shotshell (pellets [68]). • Black powder percussion handgun (69). • Air gun/rifle (16,70–75). • “Powerhead” (short nonrifled barrel with cartridge and lead projectile, used for harves- ting fish and protection against sharks [16,76]). • Pen gun (77,78). • Homemade devices (34,73,79,80). • Captive bolt pistol (i.e., animal slaughtering gun [16,23,26,34,65,81,82]). • Pneumatic hammer (83). • Nail/stud gun (16,84–91). • Starter’s pistol (73). • Blank or tear gas cartridges (21,22,92,93). 4. PRESENCE AND POSITION OF FIREARM Finding a firearm, particularly in proximity to the deceased, is supportive of sui- cide (59). In one Texas study, a firearm was found in the hand of a suicide victim, i.e., one finger in the trigger guard or at least one hand loosely gripping the barrel or grip, in 24% of all cases (94). If a handgun was used, it was found in the victim’s hands in 25.7% of the cases. Of those using a long gun (shotgun, rifle), 19.5% had the firearm in their hand, usually the left. Another study showed 20% of victims with a handgun in their hand compared with 11% with long guns (95). A German study revealed that one- third of suicide victims had a firearm in their hands (21). A gun can be positioned in a victim’s hand to conceal a homicide (94). The Texas study showed the gun on, touching, or within 30 cm (12 in.) of the body in 69% of cases, and more than 30 cm (12 in.) from the body in 7% (4 of 34 the cases involved long guns [94]). There was no correlation found between factors such as gen- der, location of the entry wound and caliber of the gun, and finding the weapon in the hands of the victim. In multishot suicides, the firearm tends to be in the hands of or near the victim (55,56,96). In rare cases when two firearms are used simultaneously, half the victims have been observed to have firearms in their hands (97). The victim usually uses the dominant hand to inflict a wound on the same side of the body (i.e., right-handed individual shoots self in right temple), but the opposite (e.g., left temple entry) does occur (16,63,98). In one series, 8% of right-handed individuals shot themselves in the left temple (98). The nondominant hand is also used (99). A weapon can rest on the side of the body opposite to the dominant hand (100). Other methods of depressing the trigger are used. A toe, a long object, or a string/cord can depress the trigger of a long gun (Fig. 1; ref. 37). A shooting apparatus can be rigged by the victim (46,60). A weapon can be braced or steadied against a firm surface (Fig. 2; refs. 46 and 60). “Missing” firearms complicate a police investigation of a suicide (16). Firearms are most commonly moved by family and friends, but emergency response personnel and police may also be responsible (94,101). The reasons for moving a firearm by those 298 The Forensic Pathology of Trauma Fig. 1. Self-inflicted firearm wounds. Depression of triggers of long guns by: (A) string attached to toe and (B) assist device. who knew the deceased include a concern about the stigma of suicide, social and reli- gious considerations, anxiety about the adverse effect of a determination of suicide on an insurance claim, and revenge (e.g., simulation of homicide). Similar motives can compel the victim (37,102).
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