Mary Ann Cotton: The Black Widow

Mary Ann Cotton (October 31,1832 – March 24,1873) was an English convicted murderer who was executed for poisoning her stepson. Despite her sole conviction for murder, she is believed to have been a serial killer who killed many others including 11 of her 13 children and three of her four husbands for their insurance policies. Her preferred method of killing was poisoning with arsenic.  Cotton's undoing came after she tried to have the son of her deceased husband sent to a workhouse. When that failed, five days later she told parish officials that Charles Edward Cotton had died. Investigations into her behavior soon showed a pattern of deaths. The body of the stepson was examined and found to contain arsenic. Cotton was convicted of his murder and sentenced to death. She was hanged at Durham Gaol. She did not die on the gallows from the breaking of her neck but died by strangulation because the rope was set too short, possibly deliberately.