Murders for profit. The case of John Donald Merrett

Forensic cases may be of historical interest because of their rarity, unique characteristics and conclusions, and potential for educating forensic scientists. The case of John Donald Merrett, who committed multiple murders for profit in Great Britain in 1926 and in 1954, is a notable example of a case in which both police and forensic scientists made serious errors, these errors leading to Merrett's acquittal when he was tried in 1927 for the shooting death of his mother. Imprisoned for forgery, Merrett was released only to resume a life of crime culminating in 1954 in the brutal murders of his wife and mother-in-law. Pursued by the police, he committed suicide. The Merrett case was of great benefit to forensic medicine in emphasizing the necessity for close teamwork among police and forensic scientists and in furthering the development of forensic ballistics.