On 16th April 2025, a significant UK Supreme Court ruling in a landmark case, For Women Scotland Ltd v The Scottish Ministers, clarified that under the Equality Act 2010, the term “woman” refers exclusively to biological sex. This judgment marks a significant shift in how the law interprets the concepts of “man,” “woman,” and “sex” within the Equality Act, explicitly stating that these terms do not include gender identity or acquired gender status, even where an individual holds a Gender Recognition Certificate (GRC).
The case arose from a challenge to legislation passed by the Scottish Government, which attempted to redefine “woman” in the context of gender representation on public boards. The Supreme Court held that such redefinition was unlawful, as the Equality Act is a reserved matter and must be interpreted consistently across the UK. The Court’s decision confirms that when applying single-sex exceptions in law, such as those governing spaces like women’s shelters, hospital wards, or competitive sports—biological sex is the determining factor.
The ruling has far-reaching consequences for employers, public bodies, and service providers. It confirms that while trans individuals continue to be protected under the characteristic of gender reassignment, they do not automatically gain access to single-sex spaces designated for the opposite biological sex, even if they hold a GRC. This distinction has a direct impact on how organisations must frame and apply policies around inclusion, access, and accommodation.
Importantly, the Gender Recognition Act 2004 remains unchanged by this ruling. Trans individuals with a GRC still receive legal recognition of their acquired gender for most purposes, including documentation, marriage, and pensions. However, the Equality Act 2010 now clearly distinguishes biological sex from legal gender in the context of single-sex services and spaces.
Employers and service providers must now carefully assess their internal policies to ensure compliance with this legal clarification. Many existing diversity and inclusion policies were built around gender identity as a basis for access and may no longer be legally compliant under the clarified Equality Act interpretation. For example, policies allowing access to facilities based solely on self-declared gender identity should now be reviewed to ensure they do not breach the law’s definition of sex-based protections.
Organisations must also ensure that any exclusion of trans individuals from a single-sex service or space is based on a legitimate aim, such as ensuring safety, privacy, or dignity and that such exclusion is proportionate. Decisions made without proper consideration of these factors may lead to legal challenges under the Equality Act’s prohibition against discrimination on the basis of gender reassignment.
To reduce the risk of claims and ensure balanced inclusion, employers should take proactive steps. First, they should review and, where necessary, revise all relevant policies, such as those related to toilet access, uniform, facility use, and HR procedures, making clear distinctions between biological sex and gender identity. Providing alternative gender-neutral or accessible options, such as unisex toilets or private changing areas, can help accommodate all staff or service users without breaching legal definitions.
Managers and HR personnel should receive training on the implications of this ruling, particularly in how to balance the rights of individuals with those of the wider workforce or service users. When an organisation decides to restrict access to a space or service on the basis of biological sex, it is advisable to document the reasons behind this decision clearly demonstrating the legitimate aim and proportionality as required under the law.
Finally, organisations should monitor further guidance expected from the Equality and Human Rights Commission (EHRC) to help navigate practical implementation. Communicating policy changes sensitively and clearly is also essential to maintaining trust and fairness among staff and stakeholders.
This ruling presents both clarity and challenge: clarity in legal terms, but challenge in operational execution. Employers and service providers must now walk a careful line—ensuring legal compliance while continuing to foster respectful, inclusive environments for all protected groups.
To find out more information or to discuss the UK Supreme Court Ruling on the definition of ‘sex’, please get in contact with our team of experts.
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