To follow on from my previous post, here is a very good reason why the European Court of Human Rights would be well advised to shut its gob and hope nobody points out all the ways in which it has already overreached its powers in this regard.
Let's just imagine for one moment that Janette's hypothetical situation comes to pass. The UK legislates to guarantee single sex spaces for women and girls, which has the effect of making gender recognition certificates essentially meaningless because men could only be considered legally women in situations where no one actually cares what sex they are.
The European Court of Human Rights says, "You can't do that."
The UK says, "Yes we can."
The European Court of Human Rights says, "No you can't, it's against trans people's human rights."
The UK says, "Oh really? Can you point to where it says that in the treaty we signed?"
The European Court of Human Rights says, "It's in the jurisprudence."
The UK says, "Your jurisprudence? That you made up? Not the treaty that we actually signed? Heh. Well we're not bound by it then. Bugger off."
And then what happens?
Lots of other countries realise they are not bound by it either.
And right wing governments in countries such as Italy and Poland start to say, "Oh, cool. We don't actually have to do the gender recognition certificate nonsense at all, do we? No one can actually make us. Right, well that's that law scrapped!"