Detection and significance of blood in firearms used in contact gunshot wounds

Abstract

Firearm fatalities in South Africa are responsible for a very large number of fatalities. For purposes of judicial administration, determination of manner of death, in particular, differentiating between homicidal, accidental and suicidal death, is one of the primary objectives in fatal shooting investigations. Determining the muzzle-target distance can assist in establishing the manner of death, since contact gunshot wounds are seldom seen in cases of homicidal or accidental death. It has been reported that muzzle-target distance can be confirmed by detection of blood back spatter on the inner and outer surfaces of the weapons. To determine whether this phenomenon was being used to assist the forensiometric analysis of fatalities, a study was undertaken whereby weapons used to inflict fatal contact gunshot wounds in victims presenting at the Pretoria MLL, were requested for biological analysis during the period June 2002 to June 2003. Of the 123 cases identified, only 30 firearms were delivered to the FSL for analysis. Blood was found on the inside of barrels in 70% of cases, and the outer surface in 40%. These figures do not correlate well with international studies. The very low retrieval rate of weapons for analysis precludes the use of an important forensiometric tool in medico-legal investigation of firearm related fatalities in Pretoria. The urgent need to develop adequate protocols with respect to police handling of weapons is hereby confirmed.