Philip Barton Key II

Philip Barton Key II was an American lawyer who served as U.S. Attorney for the District of Columbia. He is most famous for his public affair with Teresa Bagioli Sickles, and his eventual murder at the hands of her husband, Congressman Daniel Sickles of New York. Sickles defended himself by adopting a defense of temporary insanity, the first time the defense had been successfully used in the United States.