John Thomas Straffen (27 February 1930 – 19 November 2007) was an English serial killer who was the longest-serving prisoner in British legal history.
Straffen killed two young girls in the summer of 1951.
He was found to be unfit to plead and committed to Broadmoor Hospital; during a brief escape in 1952, he killed again.
This time, Straffen was convicted of murder and sentenced to death.
Reprieved because of his mental state, Straffen had his sentence commuted to life imprisonment, and he remained in prison until his death more than 55 years later.