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Landmark Cases


126 S.Ct. 2709

U.S. Supreme Court - 2006

Clark was convicted of first-degree murder for killing police officer in line of duty. He appealed. The Court of Appeals of Arizona affirmed. The Supreme Court Affirmed.

(1) Arizona's narrowing of its insanity test did not violate due process, and

(2) exclusion of evidence of mental illness and incapacity due to mental illness on issue of mens rea did not violate due process.

Arizona's narrowing of its definition of insanity, eliminating the part of M'Naghten test asking whether mental defect left defendant unable to understand what he was doing, leaving only the question whether mental disease or defect left defendant unable to understand that his action was wrong, did not violate due process; elimination of part of M'Naghten test did not offend fundamental principle or shortchange some constitutional minimum.