Background: In Sweden, approximately 90 cases of lethal violence have occurred every year for the last decade. The majority of these cases are classified as homicides (i.e. murder or manslaughter). These types of aggressive acts can be divided into reactive, with the sole purpose of hurting the victim, and instrumental, with the purpose of achieving a material or emotional goal. Research has shown that crime-scene behaviors and/or the offenders' background can be used to classify homicides and offenders as reactive or instrumental. This information can then be used in criminal profiling. However, some researchers claim that this dichotomization has lost its usefulness in modern-day research. Purpose: The purpose of this study was to examine reactive and instrumental homicides committed by men concerning their differences and similarities in characteristics. Furthermore, the purpose was to examine whether a perpetrators crime-scene behaviors could be used to categorize homicides as reactive or instrumental. Method: 94 verdicts from Swedish district courts were coded using a self-constructed coding scheme. The sample consisted of 76 reactive and 18 instrumental homicides. Only single-offender, single-victim homicides were included. Results: The inter-rater reliability for the self-constructed coding scheme varied, and tended to be lower for the variables concerning the offenders' crime-scene behavior. The results revealed a significant difference between reactive and instrumental homicides regarding the offenders' main motive. Not surprisingly, there were also differences between the two groups regarding the degrees of planning, goal-directedness, provocation and arousal. Furthermore, the offenders' degree of intoxication was higher among the reactive homicides than among the instrumental. The only difference concerning the offenders' crime-scene behaviors was that offenders in the instrumental group had transported the victim away from the crime-scene in a higher degree than offenders who had committed a reactive homicide. Direct logistic regression revealed no significant models. Discussion: Most of the differences found between reactive and instrumental homicides can be attributed to the definitions of the two types of aggression. The lack of differences between the two groups regarding crime-scene behaviors and the inability to categorize homicides regarding the perpetrators crime-scene behaviors indicates that the reactive and instrumental dichotomy is not helpful in criminal profiling, but more studies are needed to make further conclusions.
2014-11-12