Understanding the use of the insanity defense

Psychologists often are called upon to give their opinion about a legal concept, the insanity plea. Criminal cases that involve the insanity plea consistently receive the attention of the media and of legislators who contemplate restricting the use of the defense, yet there is little nationwide information on the use and possible abuse of the insanity defense. This paper reviews what little is known and suggests that in order to make psychologically and socially responsible decisions, more information is needed on the use and success of the plea.