Insanity Defence

Also found in: Dictionary, Legal.
A legal defence that a person cannot be convicted of a crime if he lacked criminal responsibility by reason of insanity—a term defined as a matter of law; the premise is that where there is no mens rea—guilty mind—by reason of insanity, there is no criminal responsibility
References in periodicals archive ?
Loughnan concedes that she is aware of "the loaded nature of the term 'madness'" (9) and the title is perhaps somewhat misleading because she casts such a wide net in discussing doctrines beyond the traditional insanity defence.
John Galligan, the civilian lawyer for Major Nidal Hasan, pictured, said he was considering an insanity defence.
Setting up an insanity defence, an attorney for Christian Karl Gerhartsreiter - who calls himself Clark Rockefeller - said his client suffered from two mental illnesses and did not know it was wrong when he snatched Reigh Boss last July during a visit to Boston.
Madoff Investment Securities are reportedly exploring an insanity defence in the 50billion-dollar fraud case.
Lisa Nowak suffered from major depression, obsessive-compulsive disorder, insomnia and "brief psychotic disorder with marked stressors", defence attorney Donald Lykkebak wrote in his notice of intent to rely on the insanity defence.
Hamlet's lawyers argued the insanity defence, based on his delusions and depression.
For example, the problems surrounding automatism, drink and the insanity defence, killing in a dream, and murder committed by a child, the 'brothel boy' of the title.