Eadweard Muybridge (1830-1904) is chiefly known as the groundbreaking photographer who invented the zoopraxiscope, the earliest form of motion picture.
Less well known but no less interesting is the fact that he shot his wife's lover, raised an insanity defense -- which was rejected by the jury -- and was then acquitted of the crime on the grounds of "justifiable homicide." According to Wikipedia:
In 1874, [while] living in the San Francisco Bay Area, Muybridge discovered that his wife had a lover, a Major Harry Larkyns. On October 17, 1874, he sought out Larkyns; said, "Good evening, Major, my name is Muybridge and here is the answer to the letter you sent my wife"; he then killed the Major with a gunshot.
Muybridge believed Larkyns to be his son's true father, although, as an adult, he bore a remarkable resemblance to Muybridge. He was put on trial for murder, but was acquitted as a "justifiable homicide." The inquiry interrupted his horse photography experiment, but not his relationship with Stanford, who paid for his criminal defense.
An interesting aspect of Muybridge's defense was a plea of insanity due to a head injury Muybridge sustained following his stagecoach accident. Friends testified that the accident dramatically changed Muybridge's personality from genial and pleasant to unstable and erratic. Although the jury dismissed the insanity plea, it is not unlikely that Muybridge did experience emotional changes due to brain damage in the frontal cortex, often associated with traumatic head injuries (for a description of Muybridge's suggested neurological injury, see Shimamura, 2002).