Methamphetamine-Associated Psychosis and Criminal Responsibility

Stimulants are among the most widely used substances in the world after cannabis, with a rapid rise in methamphetamine use in the last 15 years. Methamphetamine has a high propensity to cause psychosis ranging from transient psychosis during acute intoxication to persisting psychosis with similarities to schizophrenia. Although the former condition may not abrogate criminal responsibility, the latter is recognized as a basis for an exculpatory mental state in a majority of jurisdictions across the United States. Methamphetamine use can therefore complicate criminal responsibility evaluations. We present the literature on methamphetamine-induced psychosis, underscoring the shortfalls in existing classificatory schemes for methamphetamine-associated psychosis that can complicate forensic mental health evaluators' opinions in criminal responsibility evaluations. We offer practical considerations for forensic mental health professionals performing criminal responsibility evaluations where methamphetamine use is a concern.