Last week, the UK Supreme Court held that the terms “man,” “woman,” and “sex” in the Equality Act 2010 (EA) refer only to birth-assigned sex (‘biological’ sex) and not acquired or certificated sex on a Gender Recognition Certificate (GRC). It rejected the Scottish Ministers’ position that trans women with GRCs should be recognised as women under the EA. While the ruling has been criticised on multiple fronts, it raises particularly pressing questions about the adequacy of anti-discrimination protections for trans persons and the continued relevance of the Gender Recognition Act 2004 (GRA).

The GRA allows individuals to change their legal sex upon meeting a stringent set of criteria: diagnosis of gender dysphoria, evidence of having lived in their acquired gender for two years, and an intention to do so permanently. If granted, the issued GRC legally affirms a person’s acquired gender “for all purposes” (s.9(1)), unless disapplied by the GRA or another statute (s.9(3)). The key question before the Court was whether the EA implicitly disapplies this legal effect. The Court held that “sex” in the EA refers to biological sex, not certificated sex, meaning GRC holders are excluded from sex-based protections. It reasoned that recognising acquired sex could render some provisions—especially those on pregnancy and maternity that mention women as beneficiaries—incoherent and unworkable. In requiring a consistent understanding throughout the EA, it overruled the Inner House’s more flexible, context-sensitive interpretation that accommodated certificated sex in most provisions.

The Court assured that trans individuals remain protected under the EA. While this softens the blow of the decision, it is inadequate and raises broader concerns over the scope and significance of legal recognition.

First, the Court highlighted that trans persons are covered under the distinct protected characteristic of “gender reassignment.” This covers persons undergoing, proposing to undergo, or having undergone a process to change their sex; not limited to GRC holders. It recognises the process or fact of reassignment, and not the person’s sex. This places trans persons in a parallel but unequal category of protection, not fully mapping on to the spectrum of sex-based rights, such as equal pay entitlements, representation, access to single or separate sex services, or other substantive gender equality furthering measures that are exceptions to sex discrimination.

Second, the Court observed that trans people may claim sex discrimination based on perception— if they are perceived as a woman or suffer disadvantage similar to cis women. But these routes are legally tenuous and symbolically fraught. They rely on how others perceive a trans person’s identity, rather than recognising it as valid in its own right. It places additional burdens on trans claimants and reinforces the idea that trans women are not really women —protected only when they ‘mimic’ or are ‘misread’ as cis women.

Third, the case itself illustrates the consequences of the inability to address the structural sex-based disadvantages trans persons face. It concerned a Scottish law mandating at least 50% female representation on public boards. The government sought to include trans women with GRCs in the quota, but the Court ruled otherwise – only ‘biological’ women could count. While the Court suggested that trans representation could be pursued by other measures, it failed to consider how such measures could be operationalised, given that legal sex is binary in the UK, and GRCs are confidential. It also symbolically separates trans women from women’s equality efforts, narrowing the project of gender equality, and excluding an already marginalised group.

Fourth, the ruling also undermines the symbolic and practical value of a GRC. If legal sex does not determine one’s rights, participation, or protections under the EA—the central anti-discrimination statute—what is its value? By denying that acquired sex should justify distinct rights—even for those who meet the GRA’s stringent requirements—the Court weakened the foundation of legal gender recognition. It repeatedly suggested that trans women with and without GRCs may be indistinguishable and suffer similar disadvantages, implying that a legal document should not determine rights. If so, what meaningful function does the GRA serve?

Simultaneously, it also sets a dangerous precedent – allowing disapplication of 9(1) of the GRA absent express or necessarily implied disapplication; even when explanatory notes and the Equality and Human Rights Commission suggested otherwise.

The judgment raises a critical question: if legal sex does not secure access to rights, protections, or participation, what, then, is it for? Trans people deserve a legal system that not only symbolically recognises their identities but also protects and affirms them in practice.