THE UK SUPREME COURT’S SEX DEFINITION RULING AND ITS LESSONS FOR KENYAN EQUALITY LAW: In For Women Scotland Ltd v The Scottish Ministers [2025] UKSC 16

INTRODUCTION

In For Women Scotland Ltd v The Scottish Ministers [2025] UKSC 16, the UK Supreme Court held that the term “sex” under the Equality Act 2010 (UK) refers to biological sex, not gender identity—even in cases where an individual holds a Gender Recognition Certificate (GRC). 

This decision has stirred intense debate in the UK and beyond, not only for its legal and social impact on transgender rights but also for the policy tensions it exposes in balancing sex-based protections with gender identity recognition.

For Kenya, which is yet to enact comprehensive equality legislation that explicitly addresses transgender identities, this ruling offers significant jurisprudential and policy lessons as the country grapples with emerging questions of gender diversity, constitutional rights, and human dignity.

KEY TAKEAWAYS FROM THE UK RULING

Legal Sex Means Biological Sex

The Court clarified that, for the purposes of the Equality Act 2010, the words “man” and “woman” refer to biological sex. This affects eligibility for sex-based rights and services—such as pregnancy protections or women-only shelters.

GRC Does Not Override Sex-Based Protections

While UK law allows individuals to change legal gender via a GRC, the Court found that such recognition does not displace the biological definition of sex where it would render statutory protections “incoherent.”

Trans Protections Still Apply—Separately

Transgender individuals remain protected under the characteristic of “gender reassignment,” but not under the sex characteristic unless aligned biologically. 

POLICY AND JURISPRUDENTIAL POLICY AND JURISPRUDENTIAL IMPLICATIONS FOR KENYA

1. Kenya’s Legal Framework on Equality and Non-Discrimination

Article 27 of the Constitution of Kenya guarantees equality and freedom from discrimination, including on grounds of “sex” but is silent on “gender identity” or “gender reassignment.” Kenyan anti-discrimination law under the Constitution and Employment Act (2007) remains relatively underdeveloped on transgender rights.

What the UK ruling highlights:

Kenya urgently needs statutory clarity on whether “sex” in its laws refers to biological sex or self-identified gender, particularly in education, employment, healthcare, and public services. Courts and Parliament must anticipate these debates before rights conflicts escalate.

2. Recognition of Transgender Persons in Law

The UK’s dual-track system—biological sex for legal protections and separate trans recognition through the GRC—presents a model worth interrogating.

Kenyan relevance:

Currently, there is no gender recognition law in Kenya. Trans individuals often rely on judicial review or administrative discretion to amend identity documents—a burdensome and inconsistent process. A statutory mechanism akin to the UK’s GRA 2004 could provide legal certainty but must be crafted to avoid the UK’s current conflicts.

3. Single-Sex Spaces and Institutional Guidelines

The UK decision empowers providers of women-only services (e.g., shelters, prisons) to restrict access based on biological sex.

For Kenya:

Prisons, hospitals, schools, and public toilets are already gender-segregated, but lack clear guidelines on trans inclusion. 

The ruling suggests that Kenya must develop institutional protocols that balance sex-based protections (e.g., for women and girls) with trans rights under dignity, privacy, and equality provisions of the Constitution.

4. Impact on Employment and Workplace Equality

The UK judgment interacts with the landmark Forstater ruling, which protects gender-critical beliefs in the workplace.

For Kenya:

This raises potential tensions between freedom of belief (Article 32) and protection from discrimination (Article 27). As gender identity issues surface in Kenyan workplaces—especially in urban and civil society contexts—employers will need to adopt non-discrimination policies that are inclusive but constitutionally sound.

5. The Role of the Judiciary and Judicial Philosophy

The UK Court’s approach was one of statutory literalism, privileging legal coherence over progressive reinterpretation.

Kenyan courts—particularly the High Court and Court of Appeal—have been more progressive in interpreting constitutional rights. In C.K. (A Child) through Ripples International v Commissioner of Police (2013), for example, the Court emphasized substantive equality and human dignity as central to justice for marginalized groups.

The question for Kenyan jurisprudence will be: Can a progressive interpretation of "sex" and "equality" in our Constitution accommodate gender identity, even in the absence of legislative clarity? Or must Parliament act first?

6. Legislative Reform and Policy Development

The UK ruling is already prompting debate about reforming the Equality Act and the Gender Recognition Act. Similar pressure is inevitable in Kenya as global human rights standards evolve.

Policy guidance:

✓Review the Persons Deprived of Liberty Act, Prison Rules, and healthcare guidelines to ensure they address the rights of gender-diverse persons.

✓Amend the Registration of Persons Act to create a transparent and rights-based process for gender marker changes on official documents.

✓Develop a Gender Identity and Expression Policy Framework through the Ministry of Gender or the Kenya National Human Rights Commission (KNHRC). 

CONCLUSION

The UK Supreme Court’s reaffirmation of biological sex as the legal benchmark for equality law should not be viewed as an isolated ruling. It is a jurisprudential response to rising global tensions between trans inclusion and sex-based rights. 

For Kenya, the ruling underscores the need for proactive legal and policy interventions that reconcile our constitutional commitment to dignity and equality with emerging questions of gender identity.

As a legal community, we must ensure that the law protects all Kenyans—without erasing, excluding, or politicizing the identities of any group. Now is the time for principled engagement, policy innovation, and human rights-based legal reform.

Author's Bio: Teddy Okello is an Advocate of the High Court of Kenya and Program Lead at the Institute for Policy and Diplomacy, Nairobi, Kenya. His work focuses on review, critique and development of global frameworks for governance, finance, climate change, trade, security and geopolitics. Email: T.Okello@ipd-global.com