Excellent summary in the wake of the UK Supreme Court interpretation of the Equality Act:
If you have strong feelings about what a woman is, that’s fine – whatever they are, this judgement isn’t asking you to change them. The court has stressed that it is not its role “to adjudicate on the arguments in the public domain on the meaning of gender or sex.” Instead, its job was to try to figure out what politicians and the lawyers they worked with meant by the term when they drew up the Equality Act (2010).
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Part of the difficulty with this area of law is that when the Equality Act was written, there was very little public awareness of trans people, and that ignorance extended to the people working on the bill. Although cases of trans men getting pregnant already existed, they dismissed these as anomalous and unlikely to become relevant. Although LGBT groups such as the Equality Network advised them of the existence of non-binary people, they felt that this was a tiny minority not worth worrying about. They were similarly quick to ignore concerns raised by intersex people, and they adopted a binary definition of sex. This would inevitably lead to difficulties as public attitudes and behaviours changed, and as gaps between the law and lived reality emerged.
In the judgement released today, the judges defined ‘biological sex’ as “the sex of a person at birth.” This is, in fact, far from a watertight definition, but, helpfully, they also referenced For Women Scotland’s rather clearer “biological sex as recorded on their birth certificate.” The judges, however, are experts in law, not in medicine or biology, and they did not take evidence from anyone in that category. They therefore make statements such as “as a matter of biology, only biological women can become pregnant,” which might seem reasonable to the average person but which overlook the fact that intersex people sometimes find themselves with inaccurate birth certificates.