Mental disorder as the cause of a crime.

An offender's punishment can be reduced when a court decides that his mental disorder reduces his responsibility for what he did. Courts have sought to establish whether a mentally disordered offender's responsibility is reduced by asking whether his disorder caused the crime. Acceptance of this “causation by mental disorder” criterion has fluctuated, however. This may be because causal explanations are not the types of explanations we are accustomed to offering for the kinds of acts that bring defendants, and psychiatric witnesses, to court. More often, we offer what philosophers have called “possibility” explanations for these acts. The application of psychiatry to possibility explanations has not been widely explored. It offers the potential for the improved use of psychiatric evidence in criminal proceedings.