Roche was born on September 6, 1927, in Port Chester, New York. He was one of three children born to Irish immigrant parents. Shortly after he was born, the family moved to New York City. His father, Patrick, was an alcoholic who often assaulted his wife and once tried to kill himself. Roche's mother made money by working as a prostitute in a small apartment.

Psychological reports say that Roche spent a lot of time confined when he was young. By age 12, he started committing small crimes, which led to probation. When he was 13, he was sent to a reformatory school. During his teenage years, his mother abandoned him, and his crimes became more serious. In 1951, Roche was arrested for armed robbery and served a short prison sentence, getting released sometime before July 1952.

John Francis Roche was born on September 6, 1927, in Port Chester, New York. He was one of three children to Irish immigrant parents. The family moved to New York City shortly after his birth. Roche's father was an alcoholic who often assaulted his wife and attempted suicide. His mother worked as a prostitute. Roche had a troubled childhood, spending much time in confinement and committing petty crimes from a young age. He was sent to a reformatory school at age 13.

Roche's first known murder occurred on July 26, 1952, when Josephine Brown was strangled in Queens. He committed more murders in 1953 and 1954, including the stabbing of 85-year-old Rosa Chronik during a burglary, the rape and murder of 17-year-old Marion Brown, and the stabbing of taxi driver Alexander Jablonka. His final victim was 14-year-old Dorothy Westwater, whom he brutally attacked and killed on June 2, 1954.

The series of murders caused panic in Yorkville. Roche was arrested on June 5, 1954, after being pulled over for driving erratically. Police found a knife and a bloodstained lead pipe in his car, linking him to the murders. Roche confessed to six murders, including those of Brown and Jablonka, leading to the exoneration of two wrongly convicted men.

Roche was tried for the murder of Dorothy Westwater. He did not deny his guilt, expressing a desire to be executed rather than spend his life in prison. He was convicted of first-degree murder and sentenced to death. His execution was delayed to allow his testimony in the retrial of Paul Pfeffer, who had been wrongfully convicted for one of Roche's crimes.

Roche was executed by electric chair on January 26, 1956. Before his execution, he admitted he had falsely confessed to some murders out of sympathy for Pfeffer. Roche's last meal included fried chicken, french fries, and ice cream. He had no last words and was pronounced dead at 11:04 p.m.