Durham v. United States

Durham v. United States, 214 F.2d 862 (D.C. Cir. 1954), is a criminal case articulating what became known as the Durham rule for juries to find a defendant is not guilty by reason of insanity, that "an accused is not criminally responsible if his unlawful act was the product of mental disease or mental defect". It was to enable psychiatrists to "inform the jury of the character of [the defendant's mental disease" so that a jury could be "guided by wider horizons of knowledge concerning mental life"; so that juries could make determinations based on expert testimony about the disease. It was patterned on State v. Pike. It was adopted by only two states, for a short time, but has and continues to be influential on debate over legal insanity. The decision was criticized for leaving a jury with no standard to judge impairment of reason or control, did not define mental disease, and left the jury dependent on expert testimony.

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