Psychopathic Personality: Bridging the Gap Between Scientific Evidence and Public Policy

Our review addresses what psychopathy is, whether variants or subtypes exist (i.e., primary and secondary, unsuccessful and successful), the sorts of causal influences that contribute to psychopathy, how early in development psychopathy can validly be identified, and how psychopathy relates to future criminal behavior and treatment outcomes. Despite controversies and nuances inherent in each of these topics, the current state of scientific knowledge bears clear implications for public policy. Policy domains range from whether psychopathic individuals should be held responsible for their criminal actions to whether employers should screen job candidates for tendencies toward psychopathy. In many cases, the findings we review converge to challenge common assumptions that underpin modern applications of psychopathy measures and to call for cautions in their use. For example, contemporary measures of psychopathy, including the PCL-R, appear to evidence no special powers in predicting violence or other crime. Instead, they are about as predictive as purpose-built violence-risk-assessment tools, perhaps because they assess many of the same risk factors as those broader-band tools. Specifically, the PCL-R and other psychopathy measures derive most of their predictive utility from their “Factor 2” assessment of antisocial and disinhibitory tendencies; the “Factor 1” component of such measures, reflecting interpersonal and affective features more specific to psychopathy, play at best a small predictive role. Similarly, current measures of psychopathy do not appear to moderate the effects of treatment on violent and other criminal behavior. That is, an increasing number of studies suggest that psychopathic individuals are not uniquely “hopeless” cases who should be disqualified from treatment, but instead are general “high-risk” cases who need to be targeted for intensive treatment to maximize public safety. Misunderstandings about the criminal propensities and treatability of individuals achieving high scores on measures like the PCL-R have been perpetuated by professionals who interpret such high scores in a stereotypic manner, without considering nuances or issues of heterogeneity. A key message of our review is that classical psychopathy, whether measured by the PCL-R or other measures, is not monolithic; instead, it represents a constellation of multiple traits that may include, in varying degrees, the phenotypic domains of boldness, meanness, and disinhibition. Measures such as the PCL-R that do not directly assess features of low anxiety, fearlessness, or boldness more broadly tend to identify heterogeneous subgroups of individuals as psychopathic. As a consequence, efforts to apply one-size-fits-all public policies to psychopathic individuals may be doomed to failure. In aggregate, these conclusions may help to shed light on what psychopathy is, and what it is not, and to guide policy interventions directed toward improved public health and public safety.