: The jury found Peterson not guilty by reason of insanity. He was released two days later after a psychiatric evaluation deemed him sane. Plot Summary
: Voelker utilized a rare "irresistible impulse" insanity defense—a strategy that had not been used in Michigan since 1886. Anatomy of a Murder
The narrative follows Paul Biegler (played by James Stewart in the film), a small-town Michigan lawyer who reluctantly agrees to defend Lt. Frederick Manion. Anatomy of a Murder by Robert Traver - UP Book Review : The jury found Peterson not guilty by reason of insanity
The story is a fictionalized account of a real 1952 murder trial in which John Voelker served as the defense attorney: Anatomy of a Murder