Supreme Court settles the question of what is a woman.

As per my quote of the day, there are a lot of people who are amazed that it took the Supreme Court to settle the question of what is a woman.

But there is a reason why so many people have been equivocating over this for a decade.

We need to strike the balance which protects and ensures respect for trans people without jeopardising, or indeed completely dismantling, freedoms and protections for which women have been fighting for centuries.

As Professor Cass pointed out in her review, it is most unfortunate that this debate has become so toxic.

It cannot be right that anyone who wants to ensure that there are effective measures in place to protect women from sexual predators is at risk of being labelled a transphobe or "TERF" who hates trans people and can be demonised.

Nor is it right that anyone who wants to see trans people treated decently is in danger of being accused of wanting to abolish rights and protection for women.

There are a small number of extremists and hardliners on both sides against whom such accusations are fair, but most of those who want to protect women do not hate trans people and most of those who want to protect trans people do not hate biological women.

The Supreme Court was obviously well aware of the need to avoid throwing either women or trans people under the bus and this was crystal clear from the way Lord Hodge presented the court's ruling and urged people not to take it as a victory for one group in society over another.

The court ruled - and I believe this was exactly what parliament intended when it passed the 2010 equalities act - that the provisions in that act providing for single sex spaces for women were intended to protect biological women.

The Supreme Court made very clear that the law still protects trans people. And I want to emphasise that just as most CIS people are not sexual predators but some are, and the law must protect the vulnerable from them, most trans people are not sexual predators but some are, and the law must protect the vulnerable from them too.

It was always utterly ridiculous that male sexual predators who had been convicted, or even accused, of attacking women should have been allowed to be held in women's prisons if they claimed to identify as women. Or that people with male bodies should have been able to claim access to women's refuges if they claimed to identify as women.

Those ludicrous ideas are now as dead as the dinosaurs, and good riddance.

I suspect that we have some way to go before Britain has finished determining exactly how all this will work and how we strike the balance I referred to between protecting women and protecting trans people. I also suspect that many of the people who are celebrating the Supreme Court ruling are under the impression that it is wider in scope and more far-reaching than it actually is.

But from the clear majority welcome, or at last acceptance of the ruling, including from certain politicians who are now pretending that this has always been their position when it certainly wasn't not long ago, I think we can conclude that this is a defining moment in British politics.