Bryanna Fox
Associate Professor, University Of South Florida
Key Findings
- Among homicide offenders, the average psychopathy was categorized as “moderate” on the Psychopathy Checklist (PCL).
- There were significant differences between PCL scores and the type of homicide – with sexual homicide offenders scoring the highest on the PCL.
- Individual offenders scored lower on the PCL than individuals that offended in groups scored on the PCL.
- There were significant differences in PCL based on the homicide offender nationality.
- The link between psychopathy and homicide increased as the type of homicide became more severe.
- There was a substantial connection between psychopathy and homicide.
Description
In the article, “Psychopathic Killers: A Meta-Analytic Review of the Psychopathy-Homicide Nexus,” Fox and her co-author examine the connection between psychopathy and homicide as well as to what degree the two may be linked. The idea that psychopathy and homicide are connected is widely prevalent in popular culture but has not been connected quantitatively. To conduct their study, the researchers conducted a meta-analysis of 29 unique homicide offender samples from 22 studies, which included homicide cases from six countries. All the studies used the Psychopathy Checklist (PCL) suite to measure homicide offenders’ level of psychopathy. Additionally, the researchers coded the homicide offenses into groups to determine how psychopathy was connected to the range of violence. The results showed that among homicide offenders, the average psychopathy was categorized as “moderate” on the PCL. There were significant differences between PCL scores and type of homicide with sexual homicide offenders scoring the highest on the PCL. Individual offenders scored lower on the PCL than individuals that offended in groups scored on the PCL. There were significant differences in PCL based on the homicide offender nationality. The link between psychopathy and homicide increased as the type of homicide became more severe. Overall, the researchers found there was a substantial connection between psychopathy and homicide. They note that more research on the psychopathy-homicide link needs to be examined as well as being more representative with samples by seeking out studies from Asia, South America and other Eastern cultures.