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History of the Insanity Defense in New York State

NCJ Number
R A Carter
Date Published
48 pages
This paper reviews laws and judicial decisions bearing upon the insanity defense in New York State.
Before the M'Naghten rule, New York courts followed the established English common law, which held that no person could be held responsible for an act committed while deprived of reason. The first time the M'Naghten rule was applied in New York State was in the judge's charge to the jury in People v. Kleim (1845); however, it was up to a higher court to declare M'Naghten the rule for insanity defenses in the State. Until the State's first comprehensive insanity defense statute was passed in 1881, what constituted insanity continued to rest on judicial opinion. In the Revised Penal Law, effective September 1, 1967, the State sought to soften the rigidity of the M'Naghten rule contained in section 1120 of the former Penal Law. Recognizing the advances in psychiatric knowledge, the new law substituted a much broader concept of 'understanding' in place of the old M'Naghten word 'know.' Under this new definition, a sense of guilt as evidenced by concealment or flight is not an adequate measure of understanding of the act, since it may reflect a mere surface knowledge of the wrong done rather than a true comprehension of the nature of the act. Although there have been no revisions to section 30.05 since its enactment in 1965, the result has not been satisfactory to all. The appendixes contain a glossary of terms, the New York State insanity defense statute as of January 1982, materials on the legislative intent of section 30.05, excerpts from important court decisions in other jurisdictions, and a bibliography of 221 listings.