crimes of passion and that many psychopaths, in fact, displayed a profound deficit in emotional reactivity. Given their propensity toward violence in general (e.g., Hart & Hare, 1997), the use of instrumental or proactive violence would not be unexpected from the criminal psychopath. The general lack of empathy or remorse and the presence of shallow emotions (e.g. Hare, 1991, 1998) could be manifested in the context of their crimes and, more specifically, their homicides. On the other hand, psychopathy often is associated with impulsivity and poor behavioral controls (and problems with temper control), suggesting that violence by psy- chopaths might be highly reactive and inordinate to a particular situational provocation. A small number of studies have investi- gated this issue (Cornell et al., 1996; Hart & Dempster, 1997). Williamson, Hare, and Wong (1987) examined the nature of the violent offenses in a group of 101 Canadian offenders. They found that psychopathic offenders frequently were motivated by material gain or revenge (45.2% compared with 14.6% of the nonpsycho- paths) and did not appear to have been in a state of heightened emotional arousal at the time of the violent act. In contrast, nonpsychopathic offenders appeared to have experienced more emotional arousal during their crimes: 31.7% of the nonpsycho- paths exhibited strong emotional arousal—such as jealousy, rage, or a heated argument during their offense—compared with 2.4% of the psychopaths.
In more recent work, Cornell et al. (1996) examined the rela- tionship between psychopathy and violence in 106 male offenders from a medium-security state prison. The authors operationalized instrumental violence as violence that was goal-driven and re- quired planning without an antecedent of provocation. Reactive aggression was defined by an absence of planning or goals and, instead, involved a dispute or interpersonal conflict with the vic- tim. They found that, across their criminal histories, psychopaths (as classified using the PCL–R) were more likely to have com- mitted instrumental violence than nonpsychopaths (who were more likely to have committed reactive violence). Instrumental violence was most commonly associated with a self-reported lack of arousal or anger during the commission of the offense. Further, the victim of instrumental violence was typically a stranger, whereas reactive violence often was associated with high emo- tional arousal and a close relationship with the victim. There also is some evidence for a link between psychopathy and instrumental/ proactive aggression in nonincarcerated samples. For example, Chase, O’Leary, and Heyman (2001) found a relationship between psychopathy and the use of instrumental violence by male spousal assaulters. In their sample of 60 abusive married men, no individ- uals who were classified as being reactively aggressive were psychopathic, compared with 17% of the men who were classified as instrumentally aggressive.
There is disagreement about the extent to which the instrumental–reactive distinction is useful in conceptualizing the violence committed by psychopathic and nonpsychopathic indi- viduals. Dempster et al. (1996) investigated the institutional files of 75 adult male violent offenders participating in an inpatient treatment program. Although psychopaths were found to have committed more instrumental violence, they also had displayed impulsive behavior in the context of their offenses. Based on these findings, Hart and Dempster (1997) concluded that even if psy- chopathic individuals commit more instrumental crimes, they may be “impulsively instrumental.” It is possible, then, that psycho-
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