Turing was prosecuted for homosexuality in 1952, when such acts were still criminalised in the UK. He accepted treatment with estrogen injections (chemical castration) as an alternative to prison. Turing died in 1954, 16 days before his 42nd birthday, from cyanide poisoning. An inquest determined his death a suicide; his mother and some others believed it was accidental.[7] On 10 September 2009, following an Internet campaign, British Prime Minister Gordon Brown made an official public apology on behalf of the British government for "the appalling way he was treated." The Queen granted him a posthumous pardon on 24 December 2013.[8][9]