Human rights and the age of consent
"Up until 2004, it was possible for two gay men to be prosecuted for having sex if one was aged 16 or 17, even though it was legal for heterosexual couples.
"This blatant unfairness was only removed as a result of an ECHR ruling, one [sic] the right to a private life"
Tom Brake MP, 26 May 2015
Mr Brake is pretty much correct in what he says—the law was changed after a challenge under the European Convention on Human Rights. But the change happened in 2001, rather than 2004.
The law concerned homosexual acts performed by men—in principle, it wasn't just "gay men" who could fall foul of them.
It was a criminal offence for men to have sex with each other at all until 1967 in England and Wales, until 1980 in Scotland and 1982 in Northern Ireland. Reforms making it legal for men to carry out a "homosexual act in private" (unless they were in the armed forces or merchant navy) set the so-called age of consent at 21.
This was lowered to 18 in the 1990s.
At that point the age of heterosexual consent, and women having sex with women, was 16 in Great Britain, as it had been since 1885 and still is. Northern Ireland raised it to 17 in 1950, before lowering it to 16 again in 2008.
Mr Brake is right that both male partners could be prosecuted if one was below the age of consent.
A gay man called Euan Sutherland was concerned by this, so in 1994 he brought a case to the European Commission of Human Rights, which used to filter applications to the human rights court. In 1997, the Commission concluded that the law was discriminatory, and a breach of Mr Sutherland's right to a private life.
The Commission passed the case to the European Court of Human Rights (nowadays it would go there directly), and the government agreed to change the law. It promised to try to pass legislation bringing the age of consent for "homosexual acts" in line with that for everyone else.
So it's correct to say that the government acted because of this judgment. But it didn't take until 2004 to get the change through: the relevant Act was passed in 2000, using a procedure that bypassed the House of Lords (which had blocked two previous attempts). It came into force on 8 January 2001.
This satisfied the European Court of Human Rights, which struck out the Sutherland case a couple of months later.
When he said 2004, Mr Brake may have been thinking of the Sexual Offences Act 2003, which came into force the following year and replaced a lot of the previous laws in this area. The age of consent is now set by that Act.
Update 2 October 2015
We updated the article to clarify that the relevant law concerned homosexual acts performed by men; it didn't apply to "gay men" exclusively, and didn't apply to women at all.