The High Court has heard a two-day challenge to the City of London Corporation’s policy on who may use the Kenwood Ladies’ Pond and the Highgate Men’s Pond on Hampstead Heath, in one of the first cases to test what the Supreme Court’s ruling on the legal meaning of sex means for services run by a local authority.
The charity Sex Matters brought the judicial review, arguing that the corporation’s approach breaches the Equality Act 2010. The City of London Corporation, which manages the heath, contends that its arrangements are lawful and that it has balanced the interests of different groups of users. Judgment has been reserved.
What the policy says
In June the corporation confirmed that the ladies’ pond would be accessible to trans women and the men’s pond to trans men, while the mixed pond would remain open to everyone. The ponds are among the best-known open-air swimming sites in London, used year-round by cold-water swimmers and bathers.
The ladies’ pond opened in 1926 and has been a women-only space for a century. Its rules, like those of the men’s pond, are set by the corporation as the managing authority rather than by statute.
The arguments put to the court
Sex Matters argues that permitting people to use a facility reserved for one sex on the basis of gender identity amounts to indirect discrimination against women, and that the corporation has misread its obligations under the Equality Act. Its case relies in part on the Supreme Court’s April 2025 judgment, which held that in the Equality Act sex refers to biological sex.
The corporation argues that nothing in the Equality Act requires a blanket exclusion, and that the law allows organisations to make provision for trans people as well as for women and men. It says its decision was taken after consultation and is consistent with its duties as a public body managing a large open space.
TransLucent, a trans-led group, was granted permission to intervene in the proceedings. Its submissions are understood to focus on the practical consequences for trans people of being excluded from single-sex facilities and on how the law treats organisations that choose to be inclusive.
Why a swimming pond matters legally
The case is being watched well beyond Hampstead because it addresses a question that many public bodies have avoided since last year’s ruling: whether a service provider that opens a single-sex space to trans people on the basis of self-declared identity is acting unlawfully.
Councils, sports clubs, refuges, changing rooms and hospitals all run single-sex facilities and have been waiting for guidance about how to apply the judgment in practice. A ruling that the corporation’s approach is unlawful would force a review of policies across the public sector. A ruling that it is lawful would confirm that organisations retain discretion, provided they can justify their decisions.
The corporation has emphasised that the ponds are a unique case. They are unstaffed for much of the day, they have no changing rooms in the conventional sense, and they have been used by a self-regulating community of bathers for generations. It argues that those conditions justify an arrangement that would not necessarily be appropriate elsewhere.
What happens next
The court is expected to give judgment in writing in the coming weeks. Whatever the outcome, both sides have indicated that the case is likely to be appealed, and the question of how single-sex services should be provided is likely to reach the Court of Appeal before it is finally settled.
For bathers, the practical arrangements at the ponds remain unchanged while the case is decided. The corporation has said it will continue to apply its current policy, and the Kenwood and Highgate ponds continue to operate on their usual winter timetable.
The case also illustrates how quickly a decision about a local facility can become a national test. The pond rules were changed after a consultation that attracted thousands of responses, most of them from outside the immediate neighbourhood, and the legal challenge was funded by a campaigning organisation rather than by a local user.
