During the investigation, Turing acknowledged a sexual relationship with Murray.
Homosexual acts were illegal in the United Kingdom at that time, and so both were charged with gross indecency under Section 11 of the Criminal Law Amendment Act 1885, the same crime that Oscar Wilde had been convicted of more than fifty years earlier.
Turing was given
a choice between imprisonment or probation conditional on his agreement to undergo hormonal treatment designed to reduce libido. He accepted chemical castration via oestrogen hormone injections. A side effect of the treatment caused him to grow breasts (it is worth noting that theories around the causes of homosexuality at this time were either faulty sex horomones or more Freudian theories).
http://en.wikipedia.org/wiki/Alan_turing#Conviction_for_indecency