UK Supreme Court Excludes Trans Women from Definition of ‘Woman’

In a potentially devastating development, the UK Supreme Court has ruled that the legal definition of “woman” under the country’s Equality Act does not include transgender women, although they remain protected from discrimination as transgender individuals.

The ruling on Wednesday was applauded by anti-trans groups, while LGBTIQ+ activists warned that it could significantly impact the rights and inclusion of trans people.

The court’s five judges unanimously found that the definitions of “woman” and “sex” in the Equality Act 2010 (EA 2010) refer specifically to biological sex and therefore exclude transgender women, even those who hold Gender Recognition Certificates (GRCs).

This decision opens the door to lawfully excluding trans women—despite being legally recognised as women—from single-sex spaces and services, such as bathrooms, changing rooms, and women-only hostels.

Focus on Biological Sex

The judges ruled that “as a matter of ordinary language,” the sex discrimination provisions in the Equality Act can only be interpreted as referring to biological sex. They argued that a consistent and clear interpretation of the law depends on “man” and “woman” being defined biologically.

In a media summary, the court added that interpreting sex to include GRC-recognised gender “would also weaken the protections given to those with the protected characteristic of sexual orientation, for example, by interfering with their ability to have lesbian-only spaces and associations.”

Despite this, the court insisted that its interpretation “does not remove protection from trans people, with or without a GRC,” reiterating that transgender individuals remain protected from discrimination under the Act on the grounds of gender reassignment.

Case Brought by Anti-Trans Group

The years-long case was brought by For Women Scotland (FWS), a group that opposed the Scottish government’s position that the term “woman” includes transgender women. FWS has become known for its anti-trans stance and received financial support from Harry Potter author J.K. Rowling.

The 87-page judgment is complex, and LGBTQ+ and human rights organisations say they need time to analyse its full implications.

Rights Groups Respond

Simon Blake, CEO of UK LGBTQ+ rights group Stonewall, expressed “deep concern at the widespread implications of today’s ruling from the Supreme Court. It will be incredibly worrying for the trans community and all of us who support them.”

Blake added: “It’s important to be reminded that the Court strongly and clearly reaffirmed that the Equality Act protects all trans people against discrimination based on gender reassignment and will continue to do so.

“Once we fully digest the judgment, we will work with stakeholders across all sectors to provide as much clarity as possible.”

Amnesty International UK also responded, calling the ruling “disappointing” and affirming that “legal gender recognition is a human right.”

The organisation added, “We all have the right to live free from discrimination and fear. Trans rights are human rights.”

A Global Backslide on Trans Rights

The ruling comes amid a growing international backlash against the rights of transgender people, with many pointing to rising hostility led by right-wing movements, including the Trump administration in the United States.

As trans communities face increasing legal and social challenges worldwide, the UK Supreme Court’s ruling will be seen by many as a troubling step backward in the global fight for equality and inclusion.