This paper examines the adequacy of the M’naghten Rule, the1843 legal determination of insanity: Tests, controversies and evaluation.
Insanity is defined in a standard dictionary as more or less permanent derangement of one or more psychical functions, due to a disease of the mind. However, in law, such derangement need not always be permanent in order to relieve an individual from standing trial for an offense alleged to have been committed by the individual, to absolve an individual from responsibility for an act committed by the individual or to relieve a condemned individual from execution. There is disagreement about the meaning of insanity and about whether an individual’s condition should ever be characterized as insanity .The legal definition of insanity was originally derived from the medical profession.