On 11 July 2002, 17 judges unanimously ruled that the United Kingdom violated the Article 8 and 12 rights of transsexual people, through the continued denial of any legal mechanism to correct the gender registered for them at birth, and through maintaining their inability to marry according to their acquired gender.
The cases of Goodwin & I vs UK were a watershed, requiring specific action by the Labour government of the day, after previous administrations had dragged their heels on the issue for 32 years.
The rulling in Goodwin & I vs UK led evenutally to the enactment of the Gender Recognition Act 2004.
http://www.legislation.gov.uk/ukpga/2004/7/contents - for the actual legislation
You can download a copy of the Act from:
GIRES have put a summary of the Act ontheir website: