Enigma codebreaker Alan Turing to be given posthumous pardon

Alan Turing, the second world war Enigma codebreaker who took his own life after being convicted of gross indecency under anti-homosexuality legislation, is to be given a posthumous pardon.

The British government signalled that it is prepared to support a backbench bill that would pardon Turing, who died from cyanide poisoning at the age of 41 in 1954. He had been subjected to "chemical castration" two years earlier.

Lord Ahmad of Wimbledon, a government whip, told the House of Lords that the government would table the third reading of the Alan Turing (Statutory Pardon) Bill at the end of October if no amendments were made.

The announcement marks a change of heart by the government, which declined last year to grant pardons to the 49,000 gay men, now dead, who were convicted under the 1885 Criminal Law Amendment Act. They include Oscar Wilde.

The government threw its weight behind the private member's bill, promoted by the Liberal Democrat peer Lord Sharkey, after a debate that featured a contribution from a peer who worked at Bletchley Park, the wartime decryption centre that cracked German U-boat codes. Lady Trumpington told peers: "The block I worked in was devoted to German naval codes. Only once was I asked to deliver a paper to Alan Turing, so … I cannot claim that I knew him. However, I am certain that but for his work we would have lost the war through starvation."

Turing broke German ciphers using the bombe method, which allowed the codebreakers to crack the German Enigma code. His colleague Tommy Flowers built the Colossus computer.