LONDON — When Britain’s Supreme Court made its landmark ruling last month that only biological women are women, some people said it helped settle the long, contentious debate over the rights of transgender people and their access to single-sex spaces.
In the days since the ruling, leaders have executed screeching U-turns. Prime Minister Keir Starmer, who had declared “trans women are women,” called it “a welcome step forward” for “real clarity.”
But clarity is proving elusive.
The ruling will probably have implications on a wide range of British life: admission to changing rooms, participation in soccer clubs, how the BBC refers to transgender people in its news reports.
Britain is now trying to answer questions other democracies are addressing. Do trans people serve in the military? Are trans women welcome at a lesbian club? Allowed to run marathons in their gender category?
Transgender activists and their supporters have condemned the court’s decision as harmful, ignorant and confusing. Masses have protested, including at Parliament Square, where pro-trans demonstrators vandalized a statute of Millicent Fawcett, a Victorian-era campaigner for women’s suffrage.
Helen Belcher, managing director of the advocacy group TransActual, said the ruling and ensuing guidance “hasn’t provided clarity but chaos.”
Forcing trans women to use a toilet stall or hospital ward that doesn’t match their gender identity “outs them, breaks their privacy and is degrading,” she said. She predicted transgender people would seek protection under human rights law.
The first lawsuits are already being prepared, including one by Britain’s first transgender judge, who is appealing the judgment to the European Court of Human Rights in Strasbourg, France.
A transgender woman from Glasgow, Scotland, announced she was planning to seek asylum in Argentina.
Supporters of the decision stress that court rulings must be followed, but heads are spinning at human resources departments over exactly how. Many public and private organizations say they’re awaiting “further guidance.”
Others are dashing ahead. A day after the court ruling, the British Transport Police said transgender women who are arrested on the railway system would be strip-searched, if necessary, by male officers.
Politicians have been struggling to find the right line.
The leader of the opposition Conservative Party suggested that transgender people might simply opt to use the unisex restrooms for people with disabilities.
Labour government cabinet minister Pat McFadden said there would be no “loo police” to enforce single-sex spaces. But if there’s no enforcement, critics asked, what’s the use of rules?
The unanimous ruling by Britain’s highest court was hailed by the plaintiffs, the feminist group For Women Scotland, as returning “common sense” to decisions about who can enter a women’s shelter, for example, or serve a sentence in a women’s prison.
The plaintiffs sued the Scottish government, which had argued that trans people with government-issued gender recognition certificates had the same sex-based protections as women born female.
The United Kingdom has issued about 8,500 such certificates. The 2021 census reported that transgender people over 16 made up about 0.5 percent of the population of England and Wales, or about 262,000 people. But the Office for National Statistics said recently that the number might be an overestimate because some people might have misunderstood the question.
The Supreme Court ruled that the terms “woman” and “sex” as they appear in Britain’s Equality Act referred only to a biological woman and to biological sex — the sex one was assigned at birth.
“To reach any other conclusion,” the court wrote in an 88-page judgment, “would turn the foundational definition of sex on its head.”
The Equality and Human Rights Commission, responsible for enforcing antidiscrimination laws, announced interim guidelines.
“A trans woman is a biological man,” the commission stated, and “a trans man is a biological woman.”

In settings such as hospitals, gyms, shops, restaurants, pubs and offices, it said, trans women “should not be permitted to use the women’s facilities and trans men … should not be permitted to use the men’s facilities.”
The commission urged businesses to provide mixed facilities “where possible” and said transgender people should not be subjected to
discrimination.
After a period of public comment — expected to be full-throated — the commission is set to issue final guidance in June.
Nicola Sturgeon, the former leader of Scotland, said the guidance as written “potentially makes the lives of trans people almost unlivable.”
Susan Smith, co-director of For Women Scotland, called the criticism “frankly wrong and quite disturbing.”
“There is absolute clarity” in the ruling, she said, “but there is also resistance.”
She said her group was fighting for women’s rights to secure single-sex spaces. “People get very worked up about the toilets, but that wasn’t our priority,” she said. She imagines more unisex lavatories, or a men’s room, a women’s room and a third “that just says toilet.”
Smith said her group sued to protect women in “our most vulnerable spaces,” such as hospital wards, changing rooms and shelters for women who have suffered domestic violence.
Society had been “changed by stealth,” she said, and the ruling was fair and balanced.
It is against the law in Britain to discriminate against someone for a “protected characteristic.”
The nine characteristics are age, disability, gender reassignment, marriage and civil partnership, pregnancy and maternity, race, religion or belief, sex, and sexual orientation.
The commission stressed that transgender people need protections, too: “Where facilities are available to both men and women, trans people should not be put in a position where there are no facilities for them to use.”
Trans activists said the decision left them fearful that rights for which they had fought and won were being taken away as British institutions, one by one, issue guidelines.
A recent example: The Football Association was the first major governing body in sport to amend its rules. Starting next month, the FA said, transgender women will no longer be able to play in women’s soccer in England.
“We understand that this will be difficult for people who simply want to play the game they love in the gender by which they identify,” the FA said in a statement. “We are contacting the registered transgender women currently playing to explain the changes and how they can continue to stay involved in the game.”
The association said that there were fewer than 30 transgender women registered among millions of amateur players.
A judge in Edinburgh, Scotland, said she would issue a court order to make clear that government schools needed to provide separate toilets for girls and boys based on their biological sex. This was in response to parents discovering that their children were using gender-neutral lavatories at primary school.
Some resistance is emerging, too.
The trade union that represents civil service workers and those working in the public sector said the interim advice is “clearly not fit for purpose and is damaging in its advice and will be impossible to implement.”
More than 1,000 leaders in the arts signed an open letter warning that cultural venues “are unable to magic up new toilet facilities” and that “this kind of segregation will have significant social, cultural and economic impact.”
On London’s Hampstead Heath, the women’s-only Kenwood Ladies’ Pond welcomed transgender women in 2019. The City of London Corporation noted the court ruling but advised that “existing policies remain in effect at this time.”
There were protests.