The Imitation Game star Benedict Cumberbatch has signed an open letter to the British government calling for thousands of gay men convicted of gross indecency to be granted the same pardon as codebreaker Alan Turing.

Benedict Cumberbatch in the Imitation GameBenedict Cumberbatch as Alan Turing in The Imitation Game

Cumberbatch, who has been nominated for an Oscar for his portrayal of Turing in the biopic, has added his name to the letter, which has already been signed by 40,000 people. The letter calls on the royal family to back the campaign and give a pardon to all those who were convicted of a crime because of their sexuality.

If the pardon is granted the records of 15,000 living men would be wiped clean. Published in The Guardian, the letter begins, “The UK’s homophobic laws made the lives of generations of gay and bisexual men intolerable.”

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“It is up to young leaders of today including the Duke and Duchess of Cambridge to acknowledge this mark on our history and not allow it to stand."

“We call upon Her Majesty’s government to begin a discussion about the possibility of pardoning all the men, alive or deceased, who like Alan Turing were convicted.”

Benedict Cumberbatch in the Imitation GameCumberbatch and co-star Keira Knightley in the Oscar nominated movie.

Turing was granted a posthumous pardon by the Queen in 2013 after being convicted of gross indecency in 1952 for having a relationship with 19 year old Arnold Murray.

He was one of 49,000 men in Britain convicted of indecency under laws banning gay sex. The mathematician subsequently committed suicide in 1954, he had been rendered impotent after undergoing court order hormonal treatment designed to reduce libido.

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“Turing was one of the greatest heroes of the 20th century, a man whose work on the machines that deciphered the Enigma codes helped win World War II and who was pivotal in the development of modern computers,” the letter continues.

Other signatories to the letter include British actor and broadcaster Stephen Fry, civil rights campaigner Peter Tatchell, The Imitation Game’s director, Morten Tyldum, and Turing’s niece Rachel Barnes.