Commentary: The forensic relevance of personality disorder.

In the last half of the 20th century, research and practice in forensic mental health were focused more on major mental illness than personality disorder. This is both ironic and frustrating. The irony lies in the fact that it was alienists working in forensic settings in the late 19th and early 20th centuries who provided the first clinical descriptions of what we now call personality disorder. Mental institutions at the time housed patients suffering from “total insanity”—conditions associated with a general deterioration of mental functions. In forensic settings, however, patients had a variety of chronic but rather specific deficits in emotion or volition. This extension of the concept of mental disorder beyond the realm of total insanity greatly increased the scope and relevance of psychiatric evidence in forensic proceedings. In some respects, then, the relationship between personality disorder and forensic psychiatry is intimate—perhaps even symbiotic. The frustration, in contrast, stems from the fact that personality disorder is so important in forensic decision-making, because of its prevalence and its prognostic relevance. It appears that the lifetime prevalence of personality disorder in the United States is about 10 to 15 percent. The rate for the form of personality disorder for which the best prevalence data are available—namely, antisocial personality disorder—may be as high as 3 to 5 percent. Epidemiological data in forensic settings are scarce, but the lifetime prevalence rate may exceed 80 percent for any personality disorder and 50 percent for antisocial personality disorder. A reasonable conclusion is that prisons and jails in the United States have evolved into de facto psychiatric facilities that specialize in the institutional management of personality disorder—a purpose for which they were not designed and are not adequately resourced. With respect to prognosis, it is becoming clear that personality disorder may be associated with increased risk for criminal and violent behavior, as well as with poor response to psychosocial rehabilitation and crime reduction programs. It was, therefore, with both interest and relief that I read the article by Warren et al. in this issue of the Journal. I found the results very interesting and, perhaps more important, the article stimulated me as a reader to think more deeply about several important concerns. My comments will focus on three themes: challenges to research on the forensic relevance of personality disorder with respect to the epidemiology of personality disorder; the prognostic relevance of personality disorder; and gender differences.