The name Alan Turing might not be familiar in every household yet his contribution to the Second World War effort is now widely accepted as extraordinary and essential.

He applied his brilliant and unique mathematical mind to breaking the secret codes used for important communications by the Nazi war command. His work on the Enigma codebreaking machine is now the stuff of legend and films. Without him the Nazis could have won the war.

He is also recognised in many circles as the father of modern computing. Without his work I may not be able to type this article into my laptop. So Alan Turing was undoubtedly an intellectual giant and 2nd World War hero. Why then did he die a broken man in 1954 aged only 41?

Some speculate that Alan Turing was killed by MI5 but the official inquest recorded a verdict of suicide through consumption of cyanide. He was hauled before a court in 1952 and convicted of the crime of gross indecency which meant no more than being gay.

He was actually convicted of a crime because he had had consenting sexual relations with another adult man. This hero of the Nation some five years earlier was now a convicted criminal spared prison only because of his recognised contribution to the war effort. He was spared jail but not punishment. He was ordered to undergo experimental hormone therapy which caused significant breast enlargement and other unwelcome physical changes. In modern language the process would be described as a form of 'chemical castration'. Alan Turing described the process as horrible and humiliating.

What a shameful and heartless period in British justice that was. The Offences against the Person Act 1861 under which Alan Turing was convicted was only repealed in 1967. He pled guilty to his involvement in a sexual relationship with another man because he felt no remorse whatsoever. The relationship only came to light as a result of an investigation into a burglary at his home. Now some 61 years after his conviction Alan Turing was, on December 24th, granted a posthumous pardon under a Royal Prerogative of Mercy. He had already secured an official public apology in September 2009 by then Prime Minister Gordon Brown for his "appalling" treatment by the British justice system.

Hopefully all of us welcome this pardon and recognition that what happened to Alan Turing was wrong and morally reprehensible. However it stands as a pompous and hypocritical gesture if left on its own.

Alan Turing was criminalised for being a gay man in 1952. An estimated 75,000 other men were similarly criminalised under the same 1861 Act. A real tribute to Alan Turing would be the introduction of Turing's law which automatically pardons all those men wrongly criminalised for consenting sex with other adult males.

Under the 2012 Protection of Freedoms Act individuals convicted can apply to have their names removed. They shouldn't have to apply. They should be automatically removed. And what about those who died with their names on criminal records? They too should have their names removed.

Alan Turing was an exceptional individual but his shameful treatment under the Offences against the Person Act 1861 was not exceptional. It affected thousands of other men. Their names and criminal records should also be cleared.