Second World War code-breaker and one of the godfathers of modern computing Alan Turing has been given a royal pardon for a 61-year-old conviction for homosexual activity.
Turing, who died of cyanide poisoning in 1954, just two years after his conviction, played a crucial role in cracking the German Enigma code during the Second World War, contributing substantially to the German defeat and shortening the war by at least two years.
His conviction for "gross indecency" led not only to him being chemically castrated but also to his security clearance being removed, meaning he was no longer able to work for Government Communications Headquarters (GCHQ) where he had continued to work following service at Bletchley Park during the war.
Nearly 60 years after his death, he has been granted a pardon under the Royal Prerogative of Mercy by the Queen following a request from Justice Secretary Chris Grayling.
"Dr Alan Turing was an exceptional man with a brilliant mind. His brilliance was put into practice at Bletchley Park during the Second World War where he was pivotal to breaking the Enigma code, helping to end the war and save thousands of lives,” Grayling said.
"His later life was overshadowed by his conviction for homosexual activity, a sentence we would now consider unjust and discriminatory and which has now been repealed. Dr Turing deserves to be remembered and recognised for his fantastic contribution to the war effort and his legacy to science.”
His death of cyanide poisoning, officially considered a suicide has never been fully explained. His mother, as well as others close to the scientist, maintained it was an accident.
There has been a long campaign to clear the mathematician's name, including a well-supported e- petition and private member's bill, along with support from leading scientists such as Sir Stephen Hawking.
The pardon under the Royal Prerogative of Mercy will come into effect on Tuesday. A pardon is only normally granted when the person is innocent of the offence and where a request has been made by someone with a vested interest such as a family member. But on this occasion a pardon has been issued without either requirement being met.
In September 2009, then-prime minister Gordon Brown apologised to Dr Turing for prosecuting him as a homosexual after a petition calling for such a move.
An e-petiton - titled "Grant a pardon to Alan Turing" - received 37,404 signatures when it closed in November last year. The request was originally declined by Lord McNally on the grounds that Dr Turing was properly convicted of what at the time was a criminal offence.