is basically insane if they are unable to distinguish between right and wrong as a result of some mental disability. This rule focuses on cognition, which alone is not enough to determine whether someone is mentally disabled. The M’Naghten rule remained the definition of the insanity defense up until 1954.When the Durham case arose the insanity test was changed. Judge David Baezelon stated that, “an accused is not criminally responsible if his unlawful act was the product of mental disease or mental defect.” (Mental Health Law and the US Judicial System, pg 4) This was the foundation for the new insanity test. Baezelon worked with psychologists and psychiatrists in developing the new test and in 1962 the “Durham Rule” was founded. It was said to be better than the M’Naghten rule in that it included both cognition and volitional impairment. The M’Naghten rule didn’t include volitional impairment, which is an irresistible impulse while cognition impairment is not understanding the quality of the act. The federal courts eventually rejected the Durham rule because its definition was too broad. Alcoholics, compulsive gamblers and drug addicts had successfully used the defense to defeat a wide variety of crimes.In 1972, the American Law Institute (a panel of legal experts) developed a new rule for insanity as part of the Model Penal Code. This rule says that a defendant is not responsible for criminal conduct where he/she, as a result of mental disease or defect, did not possess “substantial capacity either to appreciate the criminality of his conduct or to conform to the requirements of the law.” (UNABOM) . Since the rule was so vague and left a number of factors up to the jury to determine only half the states have adopted the Model Penal Code rule for insanity.In 1984, congress passed the Comprehensive Crime Control Act. The Federal insanity defense now requires the de...
