It says 19 on his Wikipedia page.
This says his conviction was in 1952.
This page says the age of majority was actually 21 for both genders until 1970. So, I had it wrong, Turing would also have been considered as having a relationship with a minor if he had been with a 19 year old girl. Supposedly the actual law he was convicted under was written in a very vauge way due to "Victorian morals" (Wikipedia), and he was convicted under "Gross indecency" without much description.
But if you want to quote the Wiki articles, that's fine, but it seems like you're missing the most important parts:
From https://en.m.wikipedia.org/wiki/Alan_Turing (emphasis mine):
> During the investigation, he acknowledged a sexual relationship with Murray. Homosexual acts were criminal offences in the United Kingdom at that time, and both men were charged with "gross indecency" under Section 11 of the Criminal Law Amendment Act 1885. Initial committal proceedings for the trial were held on 27 February during which Turing's solicitor "reserved his defence", i.e., did not argue or provide evidence against the allegations.
The above flat-out contradicts what you are saying.
Just in case, here's what the Section 11 of the Criminal Law act says https://en.wikipedia.org/wiki/Criminal_Law_Amendment_Act_188...:
> The clause provided for a term of imprisonment "not exceeding two years", with or without hard labour, for any man found guilty of gross indecency with another male, whether "in public or in private". No definition was given of what, exactly, constituted "gross indecency", as Victorian morality demurred from giving precise descriptions of activity considered immoral. In practice, "gross indecency" was widely interpreted as any male homosexual behaviour short of actual sodomy, which remained a more serious and separate crime.
Nowhere in any of the above does it say anything about him being arrested or convicted because his partner wasn't at the age of majority, and all of the above say that it was for homosexual acts.
Note that both Turing and Murray were charged with the same crimes, though which of them was charged with 'committing the act' and 'being party to the commission of the act' changes from date to date.
For heterosexual sex. It wasn't until the Sexual Offences Act in 1967 that male homosexual sex was legal at all:
And even then, it was only in your own home, England and Wales, and groups of two. The law wasn't brought into full equivalence with the law for heterosexual sex until 2001:
2001! Fucking 2001! What is wrong with this country?