Forensic case profiling aspects on multiple homicides from the Cologne-Bonn metropolitan area 1985-2000

The medicolegal and subsequent criminologic interpretation of forensic and pathological findings in cases of homicide makes up an important tool of case profiling. In a retrospective study of 26 cases of "multiple homicides" involving 31 perpetrators (30 males, 1 female, mean age 33.5 years) and 73 victims (33 males, 40 females, mean age 36 years, 68 fatalities, 5 survivors), autopsy reports and prosecution authorities' files were investigated with regard to individual characteristics of victims and offenders, circumstances as well as mode of commitment. The major aim of this study was to comprehensively elucidate and characterise relevant forensic and criminologic features, which may gain importance for forensic case profiling. Forty-six victims were found in the close social environment of the perpetrator and 45 homicides were committed either in the victim's, the perpetrator's or the shared domicile. The main motives included concealment of a crime (n=13), personal conflicts/domestic arguments (n=7) and greed (n=12). The relevant injuries with regard to the cause of death were attributable to sharp force (n=13), blunt force (n=7), gunshot wounds (n=24), ligature strangulation (n=3), smothering (n=5), fire/carbon monoxide (n=4) and combined impacts (n=11). In 15 cases, so called defence injuries were found. In 5 victims a post-mortem blood alcohol concentration >1.5 g/l was determined. In six perpetrators, a severe psychiatric impairment of juridical responsibility was ascertained (Section 20 German criminal code, n=2, psychosis; Section 21 German criminal code, n=4, acute alcohol intoxication). As far as conviction data were available, 27 crimes were juridically assessed as murder, 12 as manslaughter and one as bodily harm with fatal consequences.