MEASUREMENT OF PSYCHOPATHY IN A UK PRISON POPULATION REFERRED FOR LONG-TERM PSYCHOTHERAPY

Abstract

The Hare Psychopathy Checklist Revised (PCL-R) is becoming increasingly recognized as a valid and reliable method for assessing psychopathy in male forensic populations. Previous research has supported the view that the scale has good psychometric properties, however, most work to date has been conducted with North American samples. In the present study the PCL-R was administered to 104 inmates admitted to Grendon thereapeutic prison for long-term psychotherapy. Measures of internal consistency and inter-item reliability were in the range of acceptable to good. Factor analysis using oblique rotation identified two main factors which were similar to the two-factor model proposed by Hare. Factor congruence coefficients indicated that the factors extracted were almost identical to those obtained in North American samples. Twenty six per cent of the sample were classified as psychopaths, which is close to the levels reported in North American prison settings, but considerably higher than previous research involving UK samples. This is consistent with the selection criteria for Grendon which emphasize the presence of 'personality disorder' or 'psychopathy ' as a prerequisite. Overall, the results can be viewed as offering further support to the growing literature attesting to the reliability and factor structure of the PCL-R. The classification of psychopaths in the British prison system has wide potential benefits in terms of predicting behaviour both in custody and after release and for the management and treatment of prisoners while still incarcerated. Once incarcerated, psychopaths (as measured by the Hare Psychopathy Checklist, Hare 1991) display more violent and aggressive behaviour (Hare and McPherson 1984) and are more frequently segregated from other prisoners or referred for treatment (McCord 1982). Additionally, the ability of psychopaths to lie, deceive and con is as great in prison as outside (Hare et al. 1989) and this obviously has implications for management and release. Psychopaths are often seen to work the system to their own advantage and are exceptionally skilled at securing conditional release from prison, despite their lengthy criminal histories and sometimes a history of previously violating conditions of release.