UK Supreme Court Rules Legal Definition of ‘Woman’ Refers to Biological Sex

The United Kingdom’s Supreme Court has unanimously ruled that the legal definition of “woman” under the country’s equality laws refers exclusively to biological sex, excluding transgender women from this definition.

The judgment, delivered on Wednesday, is expected to reshape how equality legislation is interpreted and enforced across the UK, particularly regarding access to single-sex spaces and services.

The case stemmed from a challenge brought by campaign group For Women Scotland (FWS) against Scottish government guidance that recognized transgender women with a Gender Recognition Certificate (GRC) as women for the purposes of public sector board appointments. The Scottish government maintained that, under the 2004 Gender Recognition Act, individuals with a GRC should be legally recognized as women and entitled to the same protections.

However, FWS argued that such recognition should be limited to those assigned female at birth, warning of potential consequences for the integrity of single-sex services such as changing rooms, hostels, and communal accommodations.

Announcing the court’s unanimous decision, Lord Patrick Hodge stated that the terms “woman” and “sex” in the Equality Act 2010 “refer to a biological woman and biological sex.” The justices concluded that interpreting “sex” as certificated sex, rather than biological sex, would undermine the coherence of the law’s protections and could grant transgender women rights not available to those assigned female at birth, particularly in areas such as pregnancy and maternity leave.

The ruling was met with strong reactions on both sides of the debate. Gender-critical campaigners and women’s rights groups celebrated the decision as a victory for clarity and the protection of single-sex spaces, while LGBTQ+ advocates and trans rights organizations expressed concern about its impact on the rights and safety of transgender people.

“The court has given the right answer: the protected characteristic of sex – male and female – refers to reality, not paperwork,” said a spokesperson for the group Sex Matters.

Despite the court’s clarification, Lord Hodge emphasized that the ruling does not strip transgender individuals of legal protection. He noted that trans women, whether or not they hold a GRC, remain protected from discrimination on the grounds of gender reassignment under existing equality laws.

“This judgment does not remove protection from trans people,” he said, urging the public not to view the decision as a triumph for one group over another.

Political leaders responded swiftly to the ruling. The UK Labour Party described the decision as bringing “clarity and confidence” to the law, while the opposition Conservatives called it a “clear victory for common sense” and pressed for updated government guidance. Government officials reiterated their support for the protection of single-sex spaces based on biological sex, assuring the public that these spaces “are protected in law and will always be protected by this Government”.

The Supreme Court’s decision comes amid a period of heightened debate over transgender rights in the UK, with advocates warning that such rulings may further marginalize the trans community. According to recent government data, hate crimes based on sexual identity have risen sharply, and activists caution that the public discourse has become increasingly polarized and hostile.

As the legal and political ramifications of the ruling unfold, both supporters and critics agree that the Supreme Court’s judgment marks a pivotal moment in the ongoing debate over sex, gender, and equality in Britain.