Billy Milligan, believed to be the first person to use multiple personality disorder in an insanity defense, has died at a Columbus hospital at the age of 59. In 1978, Milligan was acquitted of three rapes near Ohio State University. Psychologists said he had two dozen personalities that fused into a harmless one after therapy. He was released from a hospital in 1988 and continued undergoing treatment. Milligan eventually moved to California, where he was accused of threatening a judge and went through bankruptcy, before returning to Ohio 5 years ago.