Personality disorders are defined as persistent patterns of thought, emotion, behavior, and interpersonal relationships that are abnormal for the person’s culture and cause distress and dysfunction. With 11 separate personality disorder diagnoses in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), personality disorders are recognized as valid psychiatric conditions. Does the presence of a personality disorder remove culpability for criminal behavior? This is especially of concern, given that some personality disorders are associated with, or even defined by, antisocial behavior. In other words, the use of a personality disorder diagnosis in a criminal defense could lead to absurdly circular thinking: I am not responsible for my criminal behavior because I have antisocial personality disorder, which is defined by my criminal behavior.

Personality disorders differ from psychotic disorders, however, in that the cognitive abnormalities are mild. The problem is more one of motivation and disturbed interpersonal relations. Therefore, there is no reason that a personality disorder would leave someone incapable of forming criminal intent. In sum, the diagnosis has much more relevance for clinical settings than for legal ones.