A number of studies have investigated the use of the insanity defense; however, there are few reports on the use of other types of psychiatric defenses. This study explored the use of the affirmative psychiatric defense of extreme emotional disturbance (EED) in New York County (one of the five counties which comprise New York City). The results of the study indicate that, as in the case of the insanity defense, EED is rarely proffered by criminal defendants (plea rate 0.84%). The defense only prevailed on one occasion at a jury trial. While the EED defense was successful 39% of the time that it was entered, this was usually only when the prosecutor accepted the argument that was offered by the defense.