The Durham Rule is a test for the insanity defense. Derived from the Supreme Court case Durhamv. U.S., 214 F.2d 862, it states “... an accused is not criminally responsible if his unlawful act was the product of mental disease or defect.” The Durham case was ultimately overturned and is no longer used in any U.S. jurisdiction. The Durham Rule is also referred to as a “Durham Test” or “Product Test.”
See also, Insanity Defense.