In the USA the position has been far less clear with a number of state rulings going against trans people and the exclusion of trans people from recent legislation improving the rights of lesbian and gay people. However on Friday all that changed with a landmark ruling in the Federal District Court for the District of Columbia in the lawsuit by Diane Schroer against the Library of Congress. There have been rulings in favour of transgender plaintiffs under the federal sex discrimination statute but the first time a court has ruled that "sex" includes "gender identity." It is likely that there will be an appeal, but legal opinion indicates that this ruling may be difficult to overturn.
My in-box has been filled with comment on this case since the judgement was published on Friday, with a near party like atmosphere in the trans community. This is a hugely important case and will have a significant impact on attitudes towards trans people. I was going to comment earlier but have waited for comment from Jillian Weiss, who is probably the leading expert in workplace rights for trans people in the US. Her comment has been well worth the wait and I highly recommend that you read her post which is a comprehensive analysis of the case and impact of the judgement.
Landmark federal decision on transgender employment discrimination: Schroer v. Billington - Analysis from Dr Jillian Weiss
This CNN Interview with Diane Schroer, conducted before the decision, explains the background to the case and why the decision is so important.
In the UK if a public sector employer had offered a job and then withdrawn it on being informed that the applicant was planning to undergo gender reassignment, it would be a clear case of sex discrimination. Interestingly here, as in the USA, it is religious based objection that is often behind resistance to changes in legislation regarding LGBT people. Ironically Judge Jefferson in this case used treatment of religious discrimination to support gender identity discrimination as Jillian Weiss Explains
"[Judge Jefferson] recognizes that the definition of sex is a hotly contested areas, so he changes gears, and says that it is unnecessary to decide what the scientific definition of sex is. Rather, the only question is what the statutory definition of sex is. And since the Civil Rights Act of 1964 prohibits discrimination based on race, national origin, sex and religion, he analogizes the "sex" claim to the "religion" claim. He notes that no court would accept the argument that discrimination based on changing religion is allowed, even though the statute does not explicitly state this. He also notes that race discrimination has not been limited to exclude discrimination based on interracial marriage or interracial friendships.
So those many courts that have accepted a similar argument -- that sex discrimination is limited to exclude changing sex -- are wrong."
I do urge you to read Jillian's Post - Whilst specifically applicable to the USA many of the principles discussed are universal and provide a good understanding of the fundamental principles of equalities law in practice.