The Assessment and Diagnosis of “Mental Abnormalities,” Personality Disorders, and Psychopathy in Sexually Violent Predator Evaluations

The assessment and diagnosis of “mental abnormalities,” personality disorders, and psychopathy are fraught with pitfalls. These pitfalls are both theoretical and pragmatic in nature. Problems include errors in the measurement of psychological constructs, mismatches between psychological constructs and psychological definitions, poorly defined psycholegal terms, different definitions and applications of psycholegal terms across jurisdictions, and malleability of personality traits across the lifespan. We discuss this assortment of problems and review the body of research regarding the nature and assessment of these constructs in an effort to inform best practices regarding sexually violent predator evaluations. Such evaluations are intended to result in outcomes that increase public safety by containing dangerous individuals. We highlight the importance of primary and tertiary prevention of sexual (re)offending in increasing public safety. Regarding tertiary prevention, individuals convicted of sexual offenses are commonly mandated to participate in sex-offender-specific treatment and aftercare. Such treatment programs are often “one size fits all” in content. Paul (J Consult Psychol 31:104–118, 1967) suggested that an important question for psychotherapy outcome researchers to address is the following: “What treatment, by whom, is most effective for this individual with that specific problem, and under which set of circumstances?” The answer to this question for individuals displaying severe sexual behavior problems (i.e., SVPs) remains substantially unaddressed.