Durham vs. United States 1954, is a criminal case articulating what has become known as the Durham rule for juries to find a defendant is not guilty because of insanity that an accused is not criminally responsible if his unlawful act was the product of mental disease or mental defect. Apparently, the trial judge regarded this psychiatric testimony as no testimony on two grounds it did not adequately cover Durham 's condition on July 13, 1951, the date of the offense and it was not directed to Durham 's capacity to distinguish between right and wrong. They were unable to agree that for either of these reasons the psychiatric testimony could properly be considered as no testimony at all.