The Durham Test allowed for an insanity defense in the event that the crime only happened because of the defendant’s mental illness. The Durham Test is also known as the Product Test. It bears the broadest definition of insanity out of the three original tests that allow an insanity defense. It was the first standard which allowed for the mentally ill to claim an insanity defense that came out of his or her illness.
The Durham Test greatly expanded the circumstances in which an insanity defense was permitted. The Durham Test was established in 1954, in the case of Durham v. United States. It was overturned by the 1972 case United States v. Brawner.
The U.S. Court of Appeals for the District of Columbia held responsibility for establishing the Durham Test. The Court sought to establish an understanding of a legal insanity defense that would be judged in the same method of negligence. The Court attempted to require experts called upon to establish an insanity defense to explain the reasons that they believed the defendant was insane, instead of just answering yes and no questions.
Criticism of the Durham Test was similar to the criticisms levied against the M’Naghten Rule and the Irresistible Impulse Test. Critics said that instead of experts answering if the defendant could distinguish right from wrong under the M’Naghten Rules the Durham Rule allowed the experts to answer if the crime happened because of the mental illnesses of the person claiming an insanity defense, allowing for a much broader defense based on insanity. Thus, the Durham Test was criticized as allowing too lax a determination of insanity.