hind the type of instrumental violence used were examined. In 16 cases, this variable was not coded because the homicides were purely reactive with no instrumental component. Ten additional cases were not coded either because of a lack of information. Therefore, the sample size for this analysis was 99. Results indi- cated that 30 homicides (30.3%) were committed for revenge or retribution, 24 (22%) for monetary gain, 21 (19.3%) to obtain nonconsensual sex, 11 (11.1%) occurred in a conflict over a female, 7 (6.4%) were for other reasons, and 3 (2.8%) were to obtain drugs or alcohol. No significant relation was found between psychopathy and the specific type of instrumental violence committed. General type of instrumental violence. The final issue exam-
ined was whether instrumental homicides showed primary instru- mental violence or secondary instrumental violence. Purely reac- tive homicides or those that could not be coded because of insufficient information were excluded from the analysis. In addi- tion, 8 cases were excluded because it was unclear whether instru- mental violence should be coded as secondary, primary, or a combination. Therefore, the sample size for this analysis was 97. Results indicated that secondary instrumental violence had been committed in 26 (26.8%) of the homicides, whereas primary instrumental violence was perpetrated in 65 (67.0%) of the cases, and 6 homicides (6.2%) showed a combination of both types of instrumental violence. Thus, more than twice as many offenders committed primary instrumental violence compared with second- ary instrumental violence. However, no significant relation was found between psychopathy and the general type of instrumental violence committed, #2(2, N ” 91) ” .49, p ! .05.
Much research has established a strong connection between psychopathy and criminal behavior, including violence (see Hart & Hare, 1997). Psychopaths seem to have few inhibitions to prevent callous interactions with others across the life span (e.g., Hare 1996, 1998; Harpur & Hare, 1994; Porter, Birt, & Boer, 2001; Simourd & Hodge, 2000). However, the current study was the first to examine the relationship between psychopathy and the most serious form of crime—homicide. We predicted that psychopaths would show a higher level of instrumentality in their homicides than nonpsychopaths, who would be more likely to have commit- ted reactive crimes of passion. On the other hand, it is also possible that given their expected pattern of impulsivity, psychopathic offenders might have perpetrated spontaneous and reactive mur- ders (e.g., Hare, 1998).
The results clearly supported the hypothesis that psychopaths are more likely to engage in instrumental or cold-blooded homi- cides compared with nonpsychopathic individuals. In fact, almost