Thirteen months after the UK supreme court delivered its landmark ruling that sex in the Equality Act refers to biological sex, and 10 days after an updated draft “code of practice” from the Equality and Human Rights Commission (EHRC) was laid before parliament, the UK is once again rowing about single-sex spaces, and particularly toilets. Once again, the purpose and value of those spaces for women are at risk of being eclipsed by complaints from people who would prefer that they didn’t exist in a way that complies with the current law. The code confirms that there is no legal way to open a single-sex service to people of the other sex, even if they are trans. Organisations are told to address the likely disadvantage to trans people by offering alternative, mixed-sex facilities. Associations (membership organisations with rules) can be trans-inclusive if they want, as long as they do not claim to be single-sex. Bridget Phillipson, the women and equalities minister, said that avoiding any new “burden on business” was one of the reasons why the revised guidance has taken more than a year to arrive.

The angry reaction from trans rights groups was expected. “Bathroom bans”, in the US phrase, are a totemic issue. Public toilets are the only single-sex space that most of us encounter on a daily basis. Trans campaigners see the guidance as a mandate to exclude them from ordinary life. But for entry to single-sex spaces, the criteria must be sex, and the code is clear that any checks – for example, if a trans man were to be mistaken for a biological man in a women’s health setting – must be made “sensitively” to avoid discrimination or harassment.

Among those who welcomed the supreme court ruling, there is relief but also frustration. The charity Sex Matters has criticised a section of the code that says sex “should be treated as special category personal data”, and therefore kept private. This, it argues, risks making single-sex spaces harder to operate. The implications go far beyond toilets, which were never the top priority of groups including For Women Scotland, Woman’s Place UK and Fair Play for Women, which led the UK campaign for sex-based rights.

From the start, they were more bothered about spaces that are less visible but which have special status in the women’s movement: prisons, refuges, rape crisis centres, lesbian groups, women’s health centres and sports.

Attacks on the exclusionary nature of such spaces by the trans rights movement are a key reason why gender-critical feminism exists. Several of its leading figures are lesbians or sexual abuse survivors (or both) who have spoken publicly about this. Karen Ingala Smith, co-founder of the Femicide Census – which records women killed by men – bravely stuck her neck out years before Women’s Aid, the national domestic abuse charity, came out in support of single-sex services. Her book, Defending Women’s Spaces, explains from a refuge provider’s perspective why they are important to traumatised victims of domestic violence, as they rebuild their confidence and reestablish boundaries.

Trans people also suffer from high rates of domestic abuse and need access to services. There are justified concerns about inadequate funding. But mixed-sex support groups already exist, and a trend towards gender-neutral commissioning has been noted. The vast majority of public spaces and activities are already mixed-sex – which is why the Equality Act refers to single-sex ones as “exceptions”. What is not OK is the removal of this option on grounds that it is bigoted to seek a female-only space; or the claim that a service is single-sex when it is not.

The law is the law. The EHRC is only the messenger. So far, Reform UK is the only party with a plan to repeal the Equality Act. But if a campaign materialises to get rid of single-sex spaces, details on the rising levels of sexual violence will feature prominently in the arguments against it. Endlessly, radical and gender-critical feminists are accused of stigmatising transgender people and fixating on anatomy. But while there is no global body to analyse the science in the way that the International Olympic Committee has adjudicated on male advantage in sport, a vast body of evidence points to males’ far greater propensity for violence and sexual abuse.

Nature or nurture? Take your pick. Biological drives need not come into it. The point is, first, that a gender transition – particularly one made later in life – cannot erase the previous person, and everything that went into shaping them. And second, that since there is no objective test of gender identity, there is also no failsafe way to distinguish a transgender woman from a man who wishes to access female spaces.

Research is limited, in what is inevitably a highly contested area. But there are facts that back up the gender-critical view. In 2024, a government minister reported that out of 245 transgender prisoners identifying as women in England and Wales in 2024, 151 were convicted of a sexual offence – a far higher proportion than the roughly 2% of female prisoners jailed for sex crimes. Other data may point to different conclusions, but it remains scarce – for example, we don’t even know how many trans people live in England and Wales, after a question on the 2021 census was botched.

The threat posed by men to women is not the only reason why single-spaces matter. Fairness in sport and the right of women, including lesbians, to have their own groups, are also important. So are the privacy and dignity of women who are obliged to change their clothes at work, such as the nurses in Darlington who objected to undressing in front of transgender colleagues, and brought claims against their NHS employers.

But with 739,000 female victims of sexual offences in England and Wales last year, and grim trends including the huge rise in camera-enabled crimes (indecent exposure, voyeurism, filming of abuse, image-sharing), many women see the case for single-sex spaces getting stronger rather than weaker, both as a tool of prevention and as a resource for survivors. I said before that loos weren’t the main issue, and they aren’t, but mixed-sex school toilets strike me as one of the worst ideas that anyone has ever had.

The trans population faces its own challenges. The code is emphatically not a reason to disregard these. But it should not have taken the supreme court, or the EHRC, to make it clear that sacrificing single-sex spaces is not the answer.

• Susanna Rustin is a social affairs journalist and the author of Sexed: A History of British Feminism

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