Homosexuality of Alan Mathison Turing – Prosecution and punishment

Alan Mathison Turing, (23 June 1912 – 7 June 1954) was an English mathematician, logician and cryptographer. Turing is often considered to be the father of modern computer science.

Alan Mathison Turing was homosexual, living in an era when homosexuality was still both illegal and officially considered a mental illness. Subsequent to his being outed, he was criminally prosecuted, which essentially ended his career. He died not long after, under what some believe were ambiguous circumstances. Homosexuality was illegal in the United Kingdom and regarded as a mental illness and subject to criminal sanctions.

In 1952, Arnold Murray, a 19-year-old recent acquaintance of Turing's, helped an accomplice to break into Turing's house, and Turing reported the crime to the police. As a result of the police investigation, Turing acknowledged a sexual relationship with Murray, and a crime having been identified and settled, Turing and Murray were charged with gross indecency under Section 11 of the Criminal Law Amendment Act of 1885. Turing was unrepentant and was convicted of the same crime Oscar Wilde had been convicted of more than fifty years before.

Turing was given a choice between imprisonment and probation, conditional on his undergoing hormonal treatment designed to reduce libido. He accepted the estrogen hormone injections, which lasted for a year, to avoid jail. His conviction led to a removal of his security clearance and prevented him from continuing consultancy for GCHQ on cryptographic matters. At the time, there was acute public anxiety about spies and homosexual entrapment by Soviet agents, possibly due to the recent exposure of the Cambridge Five as KGB double agents.