Facets on the psychopathy checklist screening version and instrumental violence in forensic psychiatric patients.

BACKGROUND There is a recognised relationship between psychopathy and instrumental violence, but not all violence by people who meet the criteria for psychopathy is instrumental. AIMS Our aims were to compare offence types among forensic psychiatric patients with and without the Psychopathy Checklist: Screening Version (PCL: SV) criteria for psychopathy. Our specific questions were whether factor 1 - the interpersonal affective dimension - was related to instrumentality and on severity of the violent crime. Our hypothesis was that the relationship between psychopathy and instrumental violence would be dependent on the severity of the violent crime. METHODS Sixty-five male patients at the forensic psychiatric hospital in Sundsvall, all with a violent criminal history, were assessed for psychopathy through interview and records using the PCL: SV. Severity and the instrumentality of their previous violence were coded using the Cornell coding guide for violent incidents. RESULTS The interpersonal features of psychopathy (the interpersonal facet), and only the interpersonal features were significantly associated with instrumentality and severity of violence. Instrumentality was also significantly related to the severity of the violence, independent of psychopathy score. CONCLUSIONS The results indicated that, at least among forensic psychiatric patients, planning is more likely than not with respect to serious crimes. The specific link between interpersonal features of psychopathy and instrumental and severe violence suggests potential clinical value in recognising subtypes of psychopathy.