UK Supreme Court rules legal definition of a woman is based on biological sex

Meanwhile, biologists and anthropologists recognize that human biological sex is complex and exists on a spectrum, rather than being strictly binary. This ruling is founded on legal definitions, not the full scope of biological diversity. Going forward we should strive to resolve the differences between legal and biological sex so we can make judgements that are more inclusive.

This is not actually that much of a sensation -- the judges have made it clear at the very beginning that it is not their place to define what is sex or gender. The only thing they do is clarify how the words "woman" and "man" are to be interpreted in existing laws that have been made to protect women (e.g., and usually, from men).

And the result is: it is the judgement that those laws are referring to the biological sex (which it itself is recognised as being subject to some debate, too, so the judgement refers to another common definition).

That's all. It is not a redefinition or anything. I cannot really understand the enthusiasm of one side or another. It just clarifies what those laws were meant to say, and I tend to agree that anything else would most likely be an unintended reinterpretation. The judges also make it clear that if law makers want more protection for other groups, e.g., trans people, they probably need to make more laws for that.

I also find that this is a very complex topic, because it was about the question whether in sex separated prisons, it is more important to protect trans women from cis men, or to protect cis women from imposter trans women cis men. I mean -- who knows a trivial solution to that? The judges clarified basically that the original law was probably just concerned about protecting cis women from cis men, because probably no-body thought about it. And for the sake of clarifying anything, they said that "woman" probably meant "biological woman". They were tasked to decide something, so they did.

And, well, at least that's I read into this... You can have a look for yourself, maybe, before taking one side.

Are you trolling?

Biological sex is not binary. There are (at least) three criteria to be considered:

(1) cromosomes. females are XX, males are XY. But other combinations exist: XXY, XXX, XXXY, etc. There is no universal agreement of how those combinations should be best matched to the binary system.

(2) phenotype. females have a vulva, a vagina, and ovaries, males have a scrotum, a penis, and testicles. But some people have no, or half, or a large, or small of one or another. Furthermore, the phenotype might not match with the chromosomes: one example is an XY chromosome type while the person has a vulva, vagina, and internal testicles. There is no universal agreement of how those people should best be classified to the binary system -- the best is probably to recognise that they are non-binary.

(3) hormone level. females have a typical level of hormons and males have different levels. But this is not universally clear-cut. This is one of the most frequent reasons for dispute at sport events when otherwise very obvious women have hormone levels that are 'too male'. Again, no universal agreement of what to do here: ignore the hormone levels in these cases? But why? Usually, they match. But not always.

There are also male outliers that have hormone levels that are higher than for males. These males might also be excluded from sports competitions for the same reason, despite being on the right side of the binary scale, but they are too far on that side. Again -- there is no agreement whether this is still the normal male category or maybe non-binary.

And this is just the biological sex. For gender and identification, there is more. If it wasn't so serious, it would be funny how some governments define sex as binary by reducing it to biological sex or maybe assigned sex -- it is really like making a law that pi is 3.

But note that the judges here made it clear that it is not their place to make a judgement on this complex topics.

Yes, I agree that that is a consequence. But before this judgement, the laws were ambiguous, which is arguable the worst that can happen with laws.