London, April 16, 2025 — In a landmark ruling likely to reshape legal and policy interpretations of gender identity across the United Kingdom, the Supreme Court has declared that transgender women — even those holding Gender Recognition Certificates (GRCs) — do not meet the legal definition of “woman” under the Equality Act 2010.
The unanimous decision, delivered by a panel of five justices on Wednesday, stems from a legal challenge brought by the gender-critical group For Women Scotland (FWS). The ruling is expected to have significant implications for gender rights, especially concerning the provision of single-sex spaces and protections under the law.
Backed by author J.K. Rowling and advocacy group Sex Matters, FWS argued that the term “woman” in the Equality Act must be interpreted based on biological sex rather than self-identification or legal gender recognition. The Scottish government opposed this stance, pointing to the Gender Recognition Act 2004, which permits legal sex change “for all purposes” through a GRC.
However, the Supreme Court ruled that interpreting “sex” as anything other than biological would render the Equality Act “incoherent and impracticable to operate.”
“The meaning of the terms ‘sex’, ‘man’, and ‘woman’ in the [Equality Act] 2010 refer to biological sex,” the court said. “Any other interpretation would create insurmountable practical problems.”
The justices highlighted specific concerns, including the undermining of legal provisions for pregnant women, the erosion of protections for sexual orientation, and the disruption of same-sex spaces and services. They warned that extending the definition of “woman” to include trans women with GRCs would complicate areas such as women-only charities, fair competition in sports, and the public sector equality duty.
Justice Lord Hodge explained: “Interpreting sex as certificated sex would cut across the definitions of ‘man’ and ‘woman’ in the [Equality Act 2010] — and thus the protected characteristic of sex — in an incoherent way.”
The court also rejected the notion of a separate legal category of “certificated sex,” stating it would “weaken the protections given to those with the protected characteristic of sexual orientation” by blurring the legal boundaries between sex and gender identity.
The UK Government welcomed the ruling, saying it brought much-needed legal certainty.
“We have always supported the protection of single-sex spaces based on biological sex,” a government spokesperson said. “This ruling brings clarity and confidence for women and service providers such as hospitals, refuges, and sports clubs.”
The decision has sparked renewed calls from some quarters for a review or redraft of the Equality Act, while others warn it risks rolling back years of progress for the trans rights movement.
