How did the UK Supreme Court define a woman and what happens now?

LONDON -- In a judgment with far-reaching implications, the U.K. Supreme Court ruled Wednesday that a woman is someone born biologically female and that transgender women are excluded from that legal definition.

The ruling was cheered by some feminists who have campaigned to safeguard rights for women on the basis of biological sex. Trans rights campaigners were disappointed, and worry about the ruling's implications for transgender women.

The court was asked to determine the definition of a woman under Britain’s 2010 Equality Act, which sets out protections against discrimination on the basis of sex, sexual orientation, race, religion and other traits.

The case stems from a 2018 law passed by the Scottish Parliament calling for 50% female representation on the boards of Scottish public bodies. Its definition of women included trans women whose gender is legally affirmed with a Gender Recognition Certificate.

A feminist group, For Women Scotland, challenged that in court, saying the Scottish government had overstepped its powers by effectively redefining the meaning of “woman.”

The group lost a ruling in a Scottish court in 2022 but was later granted permission to take its case to the Supreme Court, which held hearings in November.

Justice Patrick Hodge said he and four other judges ruled unanimously that “the terms woman and sex in the Equality Act refer to a biological woman.”

In the law, “the words ‘sex,’ ‘woman’ and ‘man’ … mean (and were always intended to mean) biological sex, biological woman and biological man,” the judges wrote.

The judges argued that a broader definition that includes transgender people would make the Equality Act “incoherent and unworkable.”

“We can identify no good reason why the legislature should have intended that sex-based rights and protections under the (Equality Act) should apply to these complex, heterogenous groupings, rather than to the distinct group of (biological) women and girls (or men and boys) with their shared biology leading to shared disadvantage and discrimination faced by them as a distinct group,” they wrote.

The ruling makes no mention of intersex people, who also are not explicitly protected under the Equality Act.

As in other countries, the issue has polarized opinion, pitting transgender rights campaigners against “gender critical” feminists, who argue that trans women's rights should not come at the expense of those who are born biologically female.

For Women Scotland said it was “absolutely jubilant” at the ruling. “Harry Potter” author J.K. Rowling, a prominent supporter of the group, said the court victory had “protected the rights of women and girls across the U.K.”

But LGBTQ+ charity Stonewall said there is “deep concern” surrounding the ruling's consequences.

Vic Valentine, manager of the group Scottish Trans, said the judgment “seems to have totally missed what matters to trans people — that we are able to live our lives, and be recognized, in line with who we truly are.”

Amnesty International U.K. described the ruling as “disappointing,” but said it is “important to stress that the court has been clear that trans people are protected under the Equality Act against discrimination and harassment.”

The Supreme Court judges stressed that their ruling should not be seen as an attack on transgender people. They said it “does not remove or diminish the important protections … for trans people” under the Equality Act, which bans discrimination against transgender people.

It’s unclear what the ruling will mean in practice.

The judgment highlights a range of spaces and services that could be intended just for women, including “rape or domestic violence counselling, domestic violence refuges, rape crisis centers, female-only hospital wards and changing rooms.” The law already allowed for trans women to be excluded from single-sex spaces under certain circumstances, but Wednesday’s ruling appears to make such a ban easier.

The ruling could also see transgender female athletes excluded from participating in women’s and girls sports, and there could also be ramifications in workplaces.

But much depends on how the ruling is interpreted and implemented.

Hannah Ford, an employment partner at law firm Stevens & Bolton, told the BBC that because of the ruling, ensuring workplaces are welcoming places for trans people will be “an uphill battle.”

She said one positive aspect was that “at least we have simplicity and clarity. So it is in one sense a triumph of sense over legal incoherency and legal fiction.”