Insanity Defence

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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 ?
Experts say there are two levels of insanity defences.
Malvo's lawyers are presenting an insanity defence to capital murder charges in the death of FBI analyst Linda Franklin, who was shot on October 14, 2002.
Lawyers for Washington sniper suspect Lee Malvo are to mount an insanity defence at his murder trial, arguing that the teenager was a victim of 'indoctrination' by his older co-defendant John Muhammad.
Marilyn Lemak, 44, had seen her insanity defence for the 1999 killing of the children, aged three, six and seven, rejected by a jury.
However, a trial was required because the Act states that only a jury can decide if the insanity defence is valid.
Lawyers for New Yorker David Tarloff, 40, who was in court to plead not guilty to murdering Kathryn Faughey in February, will use the claim to help form the basis of a possible insanity defence.