Serial killers who died by suicide in prison custody

Pierre Chanal ([pjɛʁ ʃanal]; 18 November 1946 – 15 October 2003) was a French soldier and suspected serial killer. He was convicted of the rape and kidnapping of a young man, Balázs Falvay, whom he picked up hitchhiking in 1988. He received a ten-year sentence for the attack and was released in 1995 on probation. He was accused of murdering three of eight young men who disappeared in northeastern France between 1980 and 1987. One of his alleged victims was Trevor O'Keeffe. Chanal killed himself in prison in 2003 while on trial.

Jeanne Weber (7 October 1874 – 5 July 1918) was a French serial killer. She strangled at least 10 children, including her own. She was both convicted of murder and declared insane in 1908; she hanged herself ten years later.

Roberto Succo (3 April 1962 – 23 May 1988) was an Italian serial killer who committed several murders and other violent crimes mostly in Italy and France in the 1980s.

Antone Charles "Tony" Costa (August 2, 1944 – May 12, 1974), sometimes referred to as the Cape Cod Vampire or the Cape Cod Cannibal, was an American serial killer who was active in and around the town of Truro, Massachusetts, during 1968–1969. The dismembered remains of four women were found in or near a forest clearing where Costa grew marijuana. His crimes gained international media attention when the district attorney falsely alluded to cannibalism.