Jeffrey Dahmer (May 21, 1960 – November 28, 1994), also known as the Milwaukee Cannibal or the Milwaukee Monster, was an American serial killer and sex offender, who committed the rape, murder, and dismemberment of 17 men and boys from 1978 to 1991. Many of his later murders involved necrophilia, cannibalism, and the permanent preservation of body parts — typically all or part of the skeleton. Although diagnosed with borderline personality disorder, schizotypal personality disorder, and a psychotic disorder, Dahmer was found to be legally sane at his trial.