A very binary story: Understanding gender and sex, in and beyond the shadow of law

1. Introduction: gender and sex changes

In 2004, during the passage of the UK’s Gender Recognition Bill through parliament, shepherded by a young David Lammy as parliamentary under-secretary of state for constitutional affairs, an article was published in The Telegraph, entitled ‘Gender is no Substitute for Sex’.^[1] The article argued that – outwith the bounds of grammar in language – there is no such thing as gender; people had sexes, not genders, and the term gender, as used to describe a person, was a recent, invasive and inaccurate Americanism that was being used by UK politicians for politically correct motives.

The Gender Recognition Act 2004 (GRA) – which uses the terms sex and gender practically interchangeably – was introduced later that year. It was crafted in close consultation with trans people, and was in the main received positively, with the UK being held up as world-leading in its approach, particularly since it did not require people to undergo serious, intrusive surgeries in order to be granted a gender recognition certificate (GRC).

I wrote my first peer-reviewed article, published by Feminist Legal Studies in 2005, in response to the GRA.^[2] The title of my article mimicked that of the Telegraph story – ‘Gender is no Substitute for Sex’ – but it countered the story’s core claim. I acknowledged the positive aspects of the 2004 Act for trans people who wanted to change their birth certificate to recognise their lived gender, but I argued that the linguistic shift to gender across the socio-political landscape still leaves intact an underlying bedrock of fixed, binary sex. I argued, too, that the Act was flawed in requiring that sex/gender changes be permanent; and in its continued pathologisation of transness, since the system for legally recognising a person’s ‘acquired’ gender relies on an intrusive and medicalised process that effectively concretises gender as binary and as a discernible (and ‘ideally static’^[3]) core ‘truth’ of personal identity. It seemed to me that what sex someone identifies as would not matter quite so much were it not for the fact that sex seems to have an almost mythical, mystical power as the core truth of what it means to be human. Perhaps, I thought, this power will dissipate over time. Things can only get better, right? So where are we now, over 20 years later?

The remainder of this article begins by first discussing recent sex/gender conflicts, which culminated in the 2025 landmark decision in For Women Scotland Ltd v Scottish Ministers^[4] on the legal definition of sex in the Equality Act 2010, before stepping back in time to examine the legacy of the decision in Corbett v Corbett.^[5] Through an analysis of Corbett, which has been a key ‘influencer’ in this area of law, I will demonstrate how current legal problem-representations of gender and sex depict them as binary, biological and fundamental but separable aspects of human experience that problematically map the nature/culture divide long critiqued by feminism, centring trans women as a particularly dangerous threat to cis women’s safety in the process. The article ends by exploring what we might hope for with respect to how sex and gender are given meaning and significance in socio-political discourse. I argue that just as legal sex and gender have historical trajectories, rooted in the medico-biological discourses informing, and produced by, Justice Ormrod’s decision in Corbett, they also have future potency, which can be shaped by and reflect non-normative knowledges, stories and ways of living gender and sex, within – and outwith – the shadow of law.

2. Current legal problems: understanding gender and sex in law

In the two decades since the GRA was passed in 2004, it is clear that these problems – of how to define sex and gender, and what significance these terms should have – have not disappeared. If anything, disagreements have intensified. Public discourse in the UK is saturated with controversies and conflicts about the definition and significance of gender and sex, to the extent that some have described this moment as one of gender/sex ‘culture wars’.^[6] And conflicts are not only playing out across legacy media or social media platforms. In the tradition of what scholars have previously called naming, blaming and claiming,^[7] it seems that more people are ‘going to law’ to resolve conflicts over the meaning and significance of sex.

But the nature of the cases, and the litigants bringing them, has not been as we might have expected. Over the last 20 years since the GRA’s introduction, a linear progress narrative might have predicted ongoing successful queer and trans human-rights-based equality claims, and perhaps even additional statutory reform, intended to further refine equality-based frameworks like the gender recognition system or the Equality Act 2010, on the basis that they require updating or now languish behind those of other jurisdictions. Lawrence and Taylor have called this the ‘getting better’ discourse that is sometimes adopted by governments wishing to signal their commitment to equality and diversity, one that is built on heteronormative thresholds of key life stages (marriage, parenting etc) and colonial comparisons of ‘progress’ across jurisdictions.^[8]

Yet, leaving aside a handful of cases (for example litigating whether current legal protections for queer and trans people extend to non-binary people who do not identify as simply either male or female),^[9] legal changes that further advance the human rights of queer and trans people have not been trending. Progress has stalled, perhaps because of complacency, or, as Lawrence and Tayor suggest, because of a combination of messiness caused by fiscal uncertainty, post-Brexit instability and potentially controversial issues being relegated to the ‘too tough’ in-tray.^[10] Furthermore, some legislative attempts to extend legal protections – for instance, the Scottish government’s modernisation of the gender recognition process in 2022, intended to simplify the gender recognition process for trans people – have been met with forceful resistance or, as in the Scottish example, have ultimately failed.

Granted, the rights-based approach to queer emancipation has been widely critiqued by feminist and queer activists and scholars (among others) as being inadequate and constraining, and as having been only intermittently successful in the past in achieving inclusive equality or robust discrimination protections for queer and trans people.^[11] Yet in the last (at least) five years, there has been a sharp rise in the number of cases contesting the meaning and significance of sex and gender. These cases have largely involved courts being asked to balance the (supposedly competing) rights of trans people with or against the rights of people with different characteristics protected under the Equality Act 2010 – that is, specifically women, and people with protected (religious or gender critical) beliefs.

Contemporary conflicts have arisen over trans women’s access to women’s single-sex spaces (such as public toilets, or workplace changing rooms),^[12] sex-differentiated activities (such as women’s sporting competitions),^[13] and whether critical views and beliefs about trans people’s sex and gender can be expressed freely in the workplace.^[14] Most of this litigation has been initiated by those intent either on excluding trans people from specific services, spaces or activities, or on expressing their trans exclusionary or so-called ‘gender critical’ views. Strategies to achieve these aims have included: argumentation before employment tribunals, utilising Article 10 of the ECHR on freedom of speech, and the Equality Act 2010 discrimination and harassment provisions; and statutory interpretation-based challenges in judicial reviews of trans inclusive state policies and practices. In essence, litigation has focused on the meaning and significance of gender and sex in the context of the boundary between two historically oppressed groups, where courts are asked to arbitrate a conflict about what it means to have, be or hold views about a particular gender or sex. An apparent conflict between women’s and trans rights was also the reason given by the UK government when blocking the Gender Recognition Reform Act, passed by the Scottish parliament in 2022, from becoming law.^[15]

The decisions in these cases have mostly resulted in exclusionary legal (and socio-political) effects for queer and trans people. Legal decision-making in these contexts has largely leaned towards narrowing the scope of trans people’s rights, by promoting the category of ‘sex’ as being more significant – that is, more scientifically observable and classifiable, more ‘real’, and more legally salient – than gender. Arguments about which takes primacy culminated in the 2025 case For Women Scotland that has prompted somewhat showy celebrations from some, but anxiety and distress to many queer, trans, non-binary people, and people with variations in sex characteristics.

3. For women? Scotland in the spotlight

In April 2025 the UK Supreme Court ruled that ‘sex’ in the Equality Act 2010 means ‘biological sex’ (even though the term biological sex does not appear in the statute, and is not defined in the court’s judgment), which the court said meant ‘birth sex’. The effect of the ruling is to preclude trans people with a GRC from protection, under the protected characteristic of sex, in their legally certified gender (although trans people can still be protected under the protected characteristic of gender reassignment).^[16] The result for a trans person with a GRC is that, in contrast to the common understanding and practice that their certified ‘acquired’ gender was their legal sex for all purposes, they are now to be treated as their birth sex under the Equality Act 2010, despite the fact that it is their legally certified ‘acquired’ gender that is salient for marriage and other aspects of family law and medical law. Thus, a trans man can have a same-sex marriage with a male cisgender partner, but the same trans person’s sexual orientation would be characterised as heterosexual under the Equality Act.

It is difficult to see how this court-decreed, discordant, dual sexual citizenship, requiring continual transition back and forth across the legal, binary category of sex, is ethically justifiable. We might also question whether it is compliant with human rights such as the right to private and family life under Article 8 of the ECHR, the scope of which arguably extends to harmonious psychological and bodily integrity, and the right to a consistent and coherent, rather than fractured and fragmented, private and family life. Ironically enough, the Supreme Court in For Women Scotland maintained that the GRA protects trans people from ‘unacceptable discordance’ in their sense of identity,^[17] missing the point that their own judgment puts any potential congruent experience of identity at risk. Of course, the liberal, formal equality argument put forward by the Scottish ministers in For Women Scotland – that trans people with legal certification are ‘just like us’ – is not only hetero-cisnormatively assimilationist (and who is ‘us’, after all?), but it also makes invidious distinctions between GRC holders and non-holders that feed ideas of ‘real’ versus ‘pretend’ trans people, ostensibly justifying the abjection of non-certified trans and non-binary people. Nonetheless, this conservative, formalistic ‘equality as sameness’ framing failed to convince the Supreme Court, who held that trans people should be treated in equality law as their ‘birth sex’.

Many people worried about trans exclusion have commented on various aspects of the political problem of sex/gender we currently face in the UK (though it is not confined to the UK), including the failure of feminist solidarity, the relationship between trans exclusionary activism and far right politics,^[18] and the rise in hate crimes motivated by hostility towards transgender people.^[19] There have also been many responses to the Supreme Court judgment itself,^[20] criticising, among other things, the court’s somewhat ‘extraordinary’ failure to consider settled European law or human rights jurisprudence.^[21] For instance, rather astonishingly the court did not refer to relevant EU law, such as the Recast Equal Treatment Directive (2006/54/EC), the Gender Directive (2004/113/EC), or P v S and Cornwall County Council,^[22] all of which were still applicable during the Brexit transition period when the For Women Scotland case began its legal journey. Neither was mention made of the Third Chamber European Court of Human Rights decision of Semenya in 2023, in the context of competitive sport, that the concept of sex discrimination is expansive enough to include discrimination based on variations in sex characteristics.^[23] Nor did the Supreme Court consider the impact of their judgment – that the definitions of woman and man in the Equality Act 2010 are biological – on trans people’s rights under Articles 8, 12 or 14 (the articles under which the ECtHR in Goodwin v UK^[24] had found the UK to have violated trans people’s rights). Written arguments on Article 8 were put before the court by Amnesty International, who were permitted to intervene in the case,^[25] and consideration of whether domestic legislation is compatible with the ECHR, and how to render it so if it is incompatible, is mandated by section 3(1) of the Human Rights Act 1998. Nonetheless, there is no substantive discussion of human rights law in the For Women Scotland decision. Moreover, the ECtHR in Goodwin clearly stated that biological factors on their own did not allow the UK to explain or justify the non-recognition of trans people.^[26] Arguably this finding applies equally to the scope of gender recognition – that is, biological sex (whatever that is intended to mean) does not justify preventing a trans person from accessing equality protections in their certified sex.

Atrey also questions the court’s neglect of equality jurisprudence. In equality law generally, she explains, protected characteristics have been enumerated but not defined.^[27] Courts have avoided an essentialist approach to the characteristics, but rather taken a functional and purposive approach that focuses on ‘the disadvantages attached to grounds of discrimination’ as opposed to any apparently inherent ‘properties’ of the grounds.^[28] This allows people to claim discrimination based on protected characteristics (such as race and disability) without having to first arrive at a single agreed definition of those protected characteristics.^[29] Grounds in equality law are, therefore, not pre-discursive scientifically objective classifications but are socially constituted – and, as Atrey argues, constantly being reconstituted through the less favourable treatment of discriminators, and the application by courts of the discrimination law provisions themselves. The definition of ‘sex’ and ‘woman’ offered by the UK Supreme Court in For Women Scotland somewhat distorts the existing approach in equality law, but perhaps even more remarkably, the court does not allude to this jurisprudence at all. The court also neglects to mention the Equality and Human Rights Commission (EHRC) Employment Statutory Code of Practice;^[30] address the public sector equality duty (as set out in s 149 of the Equality Act 2010), which requires public bodies to, among other things, foster good relations between people with different protected characteristics;^[31] or engage in an intersectional analysis of combined discriminatory treatment on the grounds of sex and gender reassignment.^[32] In other words, the Supreme court is silent on many essential aspects of equality and human rights law and policy that could – should – have informed their decision.

With respect to sex discrimination specifically, sex has not always been defined, or intended to apply, solely or simply as a binary biological concept. The meaning given to sex as a ground of discrimination has, in other words, shifted over time. In European human rights law, sex discrimination has included discrimination based on gender reassignment, and variances in sex characteristics, as we saw above. In the UK, it has expanded to include gender as experienced by the person – as expressed or as perceived by the discriminator – as well as biologically based material manifestations such as child birth, pregnancy or menopause, before contracting again under the Supreme Court’s interpretation of it in For Women Scotland, which does not account for how sex discrimination has long ‘read in’ gender-based discrimination based on gender norms and stereotypes.^[33]

For instance, with respect to indirect discrimination, unfavourable treatment of individuals who are unable to work certain hours due to caring responsibilities often affects women disproportionately. This is not because of their biological sex per se, but because of gender norms that assign caregiving roles primarily to women. In Burden v Chief Constable of Hampshire Constabulary,^[34] for example, a Southampton tribunal held that an employer’s provisions, criteria and practices, individually or cumulatively, indirectly discriminated against female employees who were more likely to have childcare responsibilities. These sorts of responsibilities could include care for others, such as elderly relatives or other family members, but such responsibilities are disproportionately borne by women not because of their biological sex but because of social scripts and stereotypes about gender. More recently, the landmark case of Dobson v North Cumbria Integrated Care NHS Foundation Trust [2021] ICR 1699 found that claimants do not need to present complex statistical data to support the contention that women bear the disproportionate burden of childcare: all courts must take notice of the factual basis of this ‘childcare disparity’.^[35]

Others have condemned the judgment’s reductive representation of sexual orientation as binary and solely based on biological sex;^[36] the lack of scientific basis for the judgment that sex is biological;^[37] the complete absence of trans voices from the decision-making process (applications from trans individuals to intervene were refused without reason, while permission to intervene was given to organisations Sex Matters, Scottish Lesbians, The Lesbian Project and the LGB Alliance, who intervened in favour of the For Women Scotland position); and the failure to consider what a biological, binary interpretation of sex in the Equality Act means for people with variations in sex characteristics and for non-binary people.^[38] And while the court says it is merely ‘clarifying’ the law, and the judgment has prompted an embarrassment of endorsements on that basis, this belies the court’s approach to interpretation and narration of the law, which manifestly was selective in what it regarded as relevant sources from which to draw in developing its reasoning, in who it accepted as intervenors, and in its consideration of the possible consequences for trans people and other gender/sex non-conforming individuals.^[39] As Hannaford has pointed out, the court openly revealed its own starting view – that trans women are not women – by stating the question in the following way: ‘if sex means certified sex, how can an organisation consider the needs of, or disadvantage to, women separately from men?’^[40]

It is possible that former judge Victoria McLoud will challenge the decision on Article 6 grounds – that is, that the process lacked fairness because the Supreme Court refused her application to intervene without reasons.^[41] There will be other litigation to come, no doubt. For the time being though, in lieu of either an Act of Parliament reforming the Equality Act 2010 to expressly protect trans people under the protected characteristic of sex either in their lived or legally certified sex (for which there is clearly no appetite currently) or another Supreme Court judgment (which is unimaginable), we are stuck with For Women Scotland, and its fundamental misrecognition of the trans, non-binary and intersex people who will bear the economic, psychological and somatic cost of that judgment. In the wake of the decision, some organisations, service providers and public bodies have already begun to exclude trans and non-binary from spaces and activities they were previously using without any problems (even though the judgment gave no guidance or mandate on how to include or exclude trans people), by making changes to systems, memberships or access to services. They have done so on the basis of either the EHRC’s interim update that followed the decision (but has now been withdrawn), or how they anticipate the decision will be operationalised following the much anticipated revised Statutory Code of Practice on Services, Public Functions and Associations, overseen by the EHRC.^[42] The potential ramifications of the judgment are therefore ongoing and as yet unknown; this undermines any claim that the decision has brought legal clarity, much less other sorts of clarity.^[43]

4. In the shadow of law, what is the problem represented to be?

It is not only the legal consequences for gender/sex non-conforming people that worry commentators. The nature of public debate and public attitudes towards trans people have also prompted concern. The 2023 British Social Attitudes survey found that ‘attitudes towards people who are transgender have become markedly less liberal over the past three years’ and that ‘64% describe themselves as not prejudiced at all against people who are transgender, a decline of 18 percentage points since 2019 (82%).’^[44] Also in 2023, the UN Independent Expert on Protection Against Violence and Discrimination Based on Sexual Orientation and Gender Identity expressed concern about the ‘levels of misinformation feeding political, social, and legislative debates around legal recognition of gender identity’ in the UK,^[45] and the ‘profound and wide-ranging damage to the mental health of trans people’ caused by public political discourse.^[46]

This discourse is dominated by zero-sum game, binary logic, which prioritises sex, understood as ‘biological’, over gender, understood as ‘social’, a logic by which law is asked to police the categorical boundaries between gender and sex, and between women and men. The idea of ‘biological’ sex as it appears across this legal and public discourse is grounded in normative assumptions, some of which are contradictory. One such assumption is that we only know someone’s sex by their genitals as observed at birth: this is an assumption steeped in deference to medical knowledge and practice; and a culturally produced hetero-cis, colonial and racialised norm-framework about body shapes and congruence that categorises each of us according to legibility within that framework. Another is that ‘true’ biological sex is chromosomal, which can never be changed, notwithstanding genital surgeries or hormonal treatment: this idea is usually expressed in binary terms – one has XX or XY chromosomes denoting female and male sex respectively – whereby people with variations in sex characteristics are understood as outliers who need not bother us too much. Contemporary scientific understandings of sex have increasingly offered more complex explanations and evaluative criteria, according to a number of variables: genitals, gonads, hormones, chromosomes, the brain and, most recently, genomic sex. But as Vernica Sanz shows, the starting point is still the assumed binary nature of sex. The dichotomous framework of sex difference has dominated Western thinking since at least the eighteenth century when, according to Thomas Lacquer, medicine began to supersede religion as the ‘epistemological authority’, and colonial ideologies were utilised to hierarchise racial differences and sex dimorphism.^[47]

Sanz details the historical and ongoing contestations between medical science and other disciplines, and within science itself, to wrest control over the meaning of sex. The popularity and credibility of these various theories and epistemological claims of sex science have waxed and waned over time, with the search for a sole sex ‘master gene’ of binary sex difference eventually giving way to more interactional, multi-faceted models, and the advent of ‘neurofeminist’ insights showing the very small statistical differences between male and female brains.^[48] Yet the framework of binary biological sex seems hard to shift, with contradictions and complexities (for example in chromosomal make-up) dismissed as anomalies or ‘numerical errors’.^[49]

Dimorphic sex is also still regularly (and sometimes glibly) invoked as ‘real’ by those campaigners and scholars wishing to exclude trans people from certain spaces (often by imposing what some trans people have called ‘bio-segregation’^[50]), in contrast to the phantasm of gender, which is said to be an ‘ideology’. It is as if merely acknowledging the idea of gender as an aspect of oneself somehow denies the reality of sex, suggests Butler – as if saying that sex is constructed or mutable makes it inherently unreal or untrue.^[51] This sort of interpretation is only possible where sex realists reduce gender to a single possible meaning – gender identity – neglecting and negating the decades of work done by feminists demonstrating how gender is conceptualised and operationalised as a social construct that has material consequences; and how the sexed body (for some, ‘biological’ sex) has long been utilised as a colonial, patriarchal tool for the control of women.^[52]

Thus, if we move to ask the Carol Bacchi question – ‘what is the problem represented to be?’^[53] – we might say that the ‘problem’ as it is made out in law, but also by certain socio-political actors, is one of (real, material, scientific) biological sex being supplanted in law and in cultural life generally by (not real, constructed, imagined) psycho-social gender. Examined closely, there are two central features to this representation.

One is the harm said to be caused by trans women in particular: where once the objection to (self-declared) transgender recognition and acceptance in civic life was said to be that opportunistic and predatory men would impersonate (trans?) women to gain access to ‘real’ (cis) women-only spaces in order to cause harm,^[54] both legacy and social media – and others – have more recently moved to problematising trans women themselves as inherently dangerous, duplicitous and devious,^[55] or as taking up space and resources reserved for ‘real’ (cis) women, who are discriminated against by employers and service providers who enforce the ‘perceived’ rights of trans women to be included in such spaces.^[56] For instance, in the Peggie employment tribunal case mentioned earlier, the mere presence in the NHS Fife women’s changing room of Dr Beth Upton, a trans woman doctor, was described by the cis woman claimant, and some of those reporting on the incident, to be in and of itself a form of sexual harassment.^[57]

Another fundamental aspect of the current ‘problem-representation’ is its dyadic conceptual logic – sex versus gender, fixity versus fluidity, with biological (scientific) explanations and definitions trumping socio-psychological (phenomenological) ones. Feminists have shown how these sorts of oppositional, dichotomous pairings (male/female, public/private, reason/emotion etc) are usually expressed and operationalised hierarchically, with the first term being prioritised or privileged;^[58] feminists have also spent decades challenging the Eurocentric, colonial, pathological and patriarchal roots of the nature/culture divide upon which the sex/gender dyad is imbricated.^[59] Yet in current legal and public discourse, there is a conflict pre-baked into how we talk about and represent the human characteristics and experiences commonly referred to as gender and sex that prioritises a binary biological framing. If we look closely, however, we see that the law’s romance with the dimorphic sex model is longstanding. So when, how and why has this biological ‘turn’ come about?

5. Law, science and binary sex/gender: a polyamorous love triangle?

In some ways, it is tempting to blame Justice Roger Ormrod. A canter through the Westlaw case database suggests that he, in Corbett (decided in 1970), was the first – if not the last – to represent sex and gender in such starkly oppositional ways.^[60] His reasoning took place in the context of assessing the validity of a marriage, and it was the first reported case that determined marriage validity by reference to the (binary, fixed, biological) sex of the parties. Previous cases had addressed marriage validity, but usually by reference to whether or not the marriage could be annulled on grounds of non-consummation. The significance of consummation to an assessment of validity had therefore required the term’s careful definition by judges. What is interesting, though, is that even in consummation cases where a wife had undergone some sort of surgery to construct a ‘vaginal passage’, as it was called, judges had stated that consummation was still possible. This was held to be the case whether the wife had undergone a successful vaginal ‘lengthening’ procedure that allowed for ‘full connexion’ (as in B v B [1955] 3 WLR 237) or where there had been a more substantial vaginal construction (as in SY v SY [1962] 3 WLR 526). In other words, women with partially or fully ‘constructed’ vaginas were able to participate in valid marriages as wives. The Court of Appeal in the latter case deemed this finding was especially important to ensure that women with constructed vaginas could be held to have committed adultery, but could also be protected by criminal law if they had been raped (other than by their husbands of course, since that protection was not put in place until 1991 in England and Wales^[61]). In both B v B and SY v SY, the wife concerned was referred to throughout the case as ‘she’ and ‘her’, and there is no mention of sex – or gender – in the judgments.

Justice Ormrod was asked a slightly different question by the petitioner: either to find that there had been no consummation or to find that April Ashley was a ‘person of the male sex’, in either case the result being the nullity of the four-year marriage between her and the Scottish aristocrat Arthur Corbett, who had always known that Ashley had been registered as male at birth. Having heard the testimony of two ‘court medical inspectors’ who said there was no physical impediment to sexual intercourse (that is, there was a functioning vaginal opening), Ormrod’s answer was that Ashley was not a woman. The decision rendered the marriage void, and effectively ended the alimony payment she was receiving from Corbett.

Ormrod’s view of marriage as ‘essentially a relationship between man and woman’ meant that the validity of the (heterosexual) marriage rested on ‘whether the respondent is or is not a woman’. In framing the legal issue in this way, Justice Ormrod then took a predominantly scientific approach to the question of April Ashley’s womanhood, drawing on the testimony of six medical experts who were called, and his own medical knowledge and experience, when emphasising the need to examine closely the evidence about April Ashley’s genitals, gonads and chromosomes.

He stated:

[T]he criteria must, in my judgment, be biological, for even the most extreme degree of transsexualism in a male or the most severe hormonal imbalance which can exist in a person with male chromosomes, male gonads and male genitalia, cannot reproduce a person who is naturally capable of performing the essential role of a woman in marriage. In other words, the law should adopt, in the first place, the first three of the doctors’ criteria, i.e. the chromosomal, gonadal and genital tests, and, if all three are congruent, determine the sex for the purpose of marriage accordingly, and ignore any operative intervention.^[62]

Ormrod’s analysis relies on medical science but is still a legal determination.^[63] The complex relationship between these two powerful discourses – law and medicine – has been interrogated by feminists such as Carol Smart.^[64] Smart argued that both medicine and law can operate to disqualify the lived experiences of marginalised or minoritised individuals and communities, whereby either one or both take on a supposedly neutral truth-seeking role. In this way, powerful hegemonic, authoritative medical and legal meanings are produced and reproduced and take hold over time, their apparent neutrality masking inequity and injustice based on gender, sex, race and other structural forms of oppression. This chimes with Sanz’s characterisation of the circularity of the biological two-sex model whereby ‘meaning travels from one place to the other with no clear origin and in which challenges to the binary are buried under the weight of centuries of a two-sex model. With no clear reference, the imprecision is precisely where the power of the network resides.’^[65]

Why did Ormrod take this sort of medical, biological approach? According to his obituary published in the British Medical Journal,^[66] (Sir) Roger Ormrod was the first judge to be awarded a Fellowship of the Royal College of Physicians, having initially graduated with a law degree from Oxford and later qualifying in medicine, and serving as a major in the Royal Army Medical Corps during the Second World War before returning to practice law. He later became the co-founder of the British Academy of Forensic Sciences. The author of that obituary stated that Ormrod had a ‘profound knowledge of divorce law, and of human nature’. April Ashley may well have disagreed with the latter claim, but it is clear he was a well-respected legal figure; he was described by Dunn as ‘one of the great reforming judges of the twentieth century’,^[67] while Edward Cazelet praised Ormrod’s ability to move with shifting social tides, as well as advances in medical science, noting his ‘considerable understanding of Psychiatry’.^[68] A further Times obituary, by an unnamed author, suggests that Ormrod was a radical with a strong social conscience,^[69] and he is said to have been crucial in developing the law on no-fault divorce, emphasising the ‘vital need to protect women and children’.^[70]

Only one of these biographers (Dunn) mentions the Corbett case, and even so, only in passing. Most applaud Ormrod’s pragmatic approach that prioritised the consequences of divorce over a moral judgement of the parties’ behaviour (notwithstanding his overtly moralistic comments in the later case of A v C [1978 Fam 58] that surrogacy was ‘irresponsible bizarre and unnatural’). Ormrod himself saw the sort of broad multi-disciplinary legal and medical training he had experienced as highly beneficial in legal education and practice, going as far as to say that the practice of criminal law should involve some training in psychology.^[71] In any event, while his judgment in Corbett was an unfortunate result for April Ashley, the decision might also be described as the first step on the path towards our current legal problem-representation of gender and sex, and a consequence of Ormrod’s interdisciplinary training and ‘dual’ perspective.^[72]

Notwithstanding critical reactions at the time and since, it is certainly true that many participants in more recent legal debates on the meaning and significance of sex and gender continue to support Ormrod’s binary oppositions, and the primacy of the initial, primary term in the hierarchical dichotomy – sex, fixity, biology. Some contemporary academics and lawyers refer to Corbett as if it were still good law – including the Employment Appeal Tribunal in Forstater,^[73] in which Justice Choudhury referred approvingly to Corbett as the current authority on the definition of sex as biological and its primacy over gender as psychological. This seems odd, given that, as the Supreme Court in For Women Scotland acknowledged, the Corbett decision related to sex for the purposes of marriage.^[74] Justice Ormrod was clear to point out that:

Since marriage is essentially a relationship between man and woman, the validity of the marriage in this case depends, in my judgment, on whether the respondent is or is not a woman… The question then becomes what is meant by the word ‘woman’ in the context of a marriage, for I am not concerned to determine the ‘legal sex’ of the respondent at large.^[75]

Although the decision in Corbett was not intended to have general effect, it was applied uncritically by the Court of Appeal in the case of R v Tan.^[76] While noting that one of the defendants had lived as a woman, had undergone surgical ‘sex change operations’ and had been through a marriage ceremony with a male co-accused, the court held that the defendant was male for the purposes of section 30 of the Sexual Offences Act 1956, thereby upholding their conviction for living on the earnings of prostitution, which could only be committed by a man and which attracted a more serious penalty than the common law offence of ‘keeping a disorderly house’. The court took the view that ‘both common sense and the desirability of certainty and consistency’ required them to extend the reasoning and decision in Corbett to the criminal law context.^[77] As Lady Hale underscored in A (Respondent) v Chief Constable of West Yorkshire (Appellant), it was a ‘nonsense’ that section 30 of the 1956 Act could only be committed by a man, and ‘scarcely surprising that the Court of Appeal found it convenient to apply the Corbett reasoning in that case’.^[78]

Writing a few years after the judgment, in the Medico-Legal Journal, Ormrod suggested that Corbett demonstrates the fundamental distinction (or, as he says, conflict) between the disciplines of law and medicine: legal classifications require fixed binary categories, whereas human biology is often not reducible to ‘exclusive categories’ or ‘yes or no answers’.^[79] However, he went on to assert that, while this may present problems for jurists determining the sex of individuals, fortunately for us, ‘the law is largely indifferent to sex’.^[80] Whether or not this was the case in 1972, currently, far from being indifferent, the law – as a lever or strategy for social change – is deeply embroiled in socio-political sex/gender conflicts, as we have seen. Moreover, Ormrod’s own moralistic reasoning about the ‘natural’ role of a woman in marriage is patently clear in Corbett and other cases, such as A v C cited above, as is his lack of compassion or understanding, as demonstrated in his comments in G v G (Custody: Transsexual Parent) (1981) (unreported, Fam Div), where he said that the ‘male to female transsexual’ parent had created the problem leading to the custody dispute and that if the claimant went to visit his (sic) child ‘dressed in a way which is bizarre or aggressively feminine, or anything of that kind, it will show that his appreciation of the child’s welfare is defective’.^[81]

Needless to say this approach has prompted much critique,^[82] but the point here is that Ormrod has been represented as progressive on some fronts, but his attitude to trans women like April Ashley (to whose description as an ‘elegant pastiche’ he referred approvingly^[83]), and his framework for understanding the ‘problem’ she represented for divorce law, has bequeathed us an unhappy legacy of a binary, biological model of sex/gender that has directly influenced how the sex/gender legal ‘problem’ is represented today.

6. How might we understand sex and gender outwith the shadow of Corbett’s legacy? Or, where to from here?

Evidently, the law itself has had a central role to play in constructing concepts of sex and gender, and shaping understanding and experiences of gender and sex over time. As mentioned earlier, although some legal voices have vocally departed from the Corbett orthodoxy,^[84] many contemporary jurists and scholars – and lobbyists – continue to refer to Corbett in ongoing current legal conflicts over gender and sex.^[85] But this raises a further set of important questions: Why are people (increasingly) going to law to impose or resolve this sex/gender ‘problem’? Are these cases to be understood simply as a ‘pushback’ against a socio-political, if not legal, acceptance of an increasingly wide range of non-normative genders, sexes and sexualities? What do litigants expect to achieve, and what do they hope law can deliver? And who is choosing not to go to law, but rather to conceptualise, embody and live sex and gender outwith the shadow of law? What alternative extra-legal frameworks are there within which it is possible to understand and live genders and sexes?

These are the key questions that require us to trace how the term gender first began to be used outside the grammatical context in psychiatry and psychology to describe people’s roles and behaviour that were supposedly out of synch with their embodied sex,^[86] and how the terms gender and sex have taken on a legal life of their own. Whether or not we can or should aim to construct a world without legal binary gender and sex^[87] is to some extent beyond the point in this specific inquiry. Rather, assembling a comprehensive picture of the legal landscape since the mid-twentieth century will help us to understand how we have arrived at our current legal problem-representation. And as the political tectonic plates underpinning this legal landscape continue to move, bringing uncertainty and apprehension, understanding the past helps to prepare us for what might come next.

But law is not everything. Engaging with secondary literature on the meaning and significance of gender and sex, across a range of disciplines, including medical science, will also provide some clues to how extra-legal understandings of sex and gender have developed, in parallel, in convergence with or in opposition to law. But it will be just as important to step into the interstices where law, medicine and academic scholarship are not the dominant narratives. Social movement archives, as well as feminist and queer museums, galleries and exhibitions, are rich resources for understanding the colour and texture of people’s lives negotiated in the shadow of law, helping to produce a multi-layered socio-political repository, and living cultural history of gender and sex, including political attitudes towards, and engagements with, resistances to legal regulation.

In other words, the project before us is not only to apprehend how gender and sex have evolved, in the shadow of law, but to understand what gender and sex have looked like, and might look like, if we step outside that shadow. As Sanz has shown, sex (and sex science) has a history and, I suggest, by extrapolation, sex (and gender) must also have a future. This thought reminds us that we will not always be where we are now, and that there will be other ways of seeing and living genders and sexes. Some scholars have focused on questions about the future of legal gender, and by association, legal sex, such as ‘[w]hat would be the social, cultural and political implications if the ways that state law treated people’s sex/gender radically changed?’^[88] Equally, it is essential to imagine sexes and genders outwith law, as layers of living that inflect and are inflected by other prisms of selfhood.

In the context of increasing ascendancy of AI, virtual reality and ‘Reality Labs’, it is not clear what place and significance material and embodied aspects of sex and gender will continue to hold – though it is clear that machine-based language models can replicate embedded sex/gender, race and other legal and socio-political biases.^[89] This radical uncertainty about the future requires us to keep in mind the question of how we might move through the world, and through change, with hope for ‘the world as we might desire it to be’ as Tanya Serisier has said.^[90] After all, diverse and inclusive communities, material or otherwise, are built through trust, collaboration, curiosity and shared, experiential learning and practice, not simply the threat of legal intervention or even the promise of equal protection. Recognising this allows us to be proactive in our collective attempts to (re)produce non-normative knowledges, stories and ways of living genders and sexes, and to create change and promote intersectional and interstitial ‘radical equity’ – that is, transformation through affirmative solidarity and allyship practices and passions, within and outwith law.

1. Frank Johnson, ‘Gender is no Substitute for Sex’ Daily Telegraph (24 February 2004). Lammy has spoken publicly in support of trans rights – see, eg, Caitlin Prowle, ‘Lammy on Trans Rights: “There are some Dinosaurs on the Right” and “in our own Party”’ (LabourList, 27 September 2021) <https://labourlist.org/2021/09/anti-trans-members-are-dinosaurs-who-want-to-hoard-rights-says-lammy/> accessed 30 June 2026. David Lammy is, at the time of writing, one of the few prominent Labour front bench MPs who has been consistent and outspoken in his support of trans people’s equality and human rights. ↑

2. Sharon Cowan, ‘“Gender is no Substitute for Sex”: A Comparative Human Rights Analysis of the Legal Regulation of Sexual Identity’ (2005) 13(1) Feminist Legal Studies 67–96. ↑

3. ↑

4. For Women Scotland Ltd v Scottish Ministers [2025] UKSC 16. ↑

5. Corbett v Corbett (otherwise Ashley) [1970] 2 All ER 33. ↑

6. Bart Cammaerts, ‘The Abnormalisation of Social Justice’ (2022) 33(6) Discourse and Society 730; Sandra Duffy, ‘Moral Panics and Legal Projects’ (2025) 1(1) Gender and Justice 78. ↑

7. William Felstiner, Richard Abel and Auston Sarat, ‘The Emergence and Transformation of Disputes: Naming, Blaming, Claiming…’ (1980–1981) 15(3–4) Law and Society Review 631. ↑

8. Matson Lawrence and Yvette Taylor, ‘The UK Government LGBT Action Plan: Discourses of Progress, Enduring Stasis, and LGBTQI+ Lives “Getting Better”’ (2020) 40(4) Critical Social Policy 586. ↑

9. Taylor v Jaguar Land Rover Ltd [2020] ET/1304471/2018 (acknowledging that the protected characteristic of gender reassignment in the Equality Act 2010 can include non-binary people); Mx M v the Secretary of State for the Home Department [2020] UKUT 313 (IAC) (stating that the asylum protection ground of sexual orientation includes non-binary people); R (Elan Cane) v the Secretary of State for the Home Department [2021] UKSC 56 (holding that the UK does not recognise other than male or female markers on passports); Lockwood v Cheshire and Wirral NHS Trust & Others [2025] ET/240211/2024 (holding that the protected characteristic of gender reassignment does not automatically include non-binary people). For discussion of different approaches across Europe see Tuur Desloovere, ‘Transgender Laws in Transition: European Courts on Non-Binary Gender Recognition’ (Oxford Human Rights Blog, 11 August 2019) <https://ohrh.law.ox.ac.uk/transgender-laws-in-transition-european-courts-on-non-binary-gender-recognition/> accessed 30 June 2026. ↑

10. Lawrence and Taylor (n 8). ↑

11. The literature is vast but see, eg, Carol Smart, Feminism and the Power of Law (Routledge 1989); Elizabeth Kingdom, What’s Wrong with Rights?: Problems for Feminist Politics of Law (Edinburgh University Press 1991); Dean Spade, Normal Life: Administrative Violence, Critical Trans Politics, and the Limits of Law (Duke University Press 2015) esp ch 2; Libby Adler, Gay Proiri: A Queer Critical Legal Studies Approach to Law Reform (Duke University Press 2018); Ratna Kapur, ‘The Sexual Subaltern and Law: Postcolonial Queer Imaginaries’ in Joel Fischel and Brenda Cossman (eds), Enticements: Queer Legal Studies (New York University Press 2024). ↑

12. See, eg, Peggie v Fife Health Board [2025] ET(Scotland)/4104864/2024; Kelly v Leonardo UK Ltd [2025] ET(Scotland)/8001497/2024; O’Neil v UCU [2025] ET/3309730/2023 & ET/3309731/2023 <https://assets.publishing.service.gov.uk/media/684992653a2aa5ba84d1df3d/Dr_D_O_Neill___Other_v_University_and_College_Union_3309730.2023___Other_FMH_Reserved_Judgment.pdf> accessed 30 June 2026. ↑

13. Haynes v Thomson (on behalf of the English Blackball Pool Federation) [2025] EWCC 50, Canterbury County Court, K01CT207. See also the European Court of Human Rights Third Chamber decision on sport and differences in sex characteristics: Semenya v Switzerland App no 10934/21 (ECtHR, 11 July 2023). ↑

14. See, eg, Forstater v Centre for Global Development Europe [2021] UKEAT 0105/20/JOJ; Higgs v Farmor’s School [2025] EWCA Civ 109; Mackereth v DWP [2022] EAT 99; Adams v Edinburgh Rape Crisis Centre [2024] SLT (Tr) 89. ↑

15. For discussion, see Sharon Cowan, ‘Trans Rights, Queer Times: In Search of a New Hope’ (2025) 47(1) Journal of Social Welfare and Family Law 108. ↑

16. For Women Scotland (n 4). For discussion of how the case arose, see Cowan (n 15). Importantly, the judgment does not apply in Northern Ireland, which has its own equality provisions. For discussion, see CRG Murray and Aoife O’Donoghue ‘The Definition of Sex: For Women Scotland (FWS) Ltd v The Scottish Ministers’ (2025) 6(AD1) Northern Ireland Legal Quarterly 73. ↑

17. At para 100. ↑

18. See, eg, Ruth Pearce, Sonja Erikainen and Ben Vincent, ‘TERF Wars: An Introduction’ (2020) 68(4) The Sociological Review 677; Jules Gill-Peterson, A Short History of Transmisogyny (Verso Books 2024); Gina Gwenffrewi, ‘Isla Bryson and the Burden of Representation: Inflammatory Media Coverage of Trans Women in the UK in 2023’ in Ben Colliver and others (eds), Contemporary Issues in Transphobic Hate and Prejudice: Transforming the Narrative (Routledge 2026). ↑

19. Although the number of these offences in England and Wales reported to the police fell by 2 per cent in 2023–24, the number (4,780) was almost double that reported in 2020–21 (2,799) (which itself was more than double the number recorded in 2016–17). See Home Office, ‘Hate Crime, England and Wales, Year Ending March 2024’ (gov.uk, 10 October 2024) <https://www.gov.uk/government/statistics/hate-crime-england-and-wales-year-ending-march-2024/hate-crime-england-and-wales-year-ending-march-2024#section2> accessed 30 June 2026. See also ‘Transgender Hate Crimes Recorded by Police Go Up 81%’ (BBC News, 27 June 2019) <https://www.bbc.co.uk/news/uk-48756370> accessed 30 June 2026. ↑

20. For instance, Cowan (n 15); Alexander Maine ‘For Women Scotland: An Interpretation of Equality Rooted in Biology’ (2025) 47(2–3) Journal of Social Welfare and Family Law 377; Kenneth Norrie, ‘Case Comment: For Women Scotland Ltd v The Scottish Ministers [2025] UKSC 16’ [2025] Juridical Review 182; Cal Horton, ‘Towards a Theory of Cis-Supremacy: Conceptualising Ongoing Barriers to Trans Equality’ (2025) 59 Sociology 485; A James Hannaford, ‘Bad Law, Worse History and the Role of the Court: Re-reading For Women Scotland Ltd v The Scottish Ministers’ (2025) 2 Exceptions 73; Crash Wigley, ‘For Women Scotland: A Legal Critique’ (Trans Legal Project, 29 April 2025) <https://www.translegalproject.org/post/for-women-scotland-a-legal-critique> accessed 30 June 2026; Shreya Atrey, ‘Grounds in Equality Law: Before and After For Women Scotland’ (2026) 89(3) MLR 379. ↑

21. Wigley (n 20); Conor Gearty, ‘Unwelcome Remnant’ (2025) 47(18) London Review of Books <https://www.lrb.co.uk/the-paper/v47/n18/conor-gearty/unwelcome-remnant> accessed 30 June 2026. Gearty argues that the Supreme Court are ‘quietly editing the Human Rights Act out of existence’. See also Lewis Graham, ‘Has the UK Supreme Court Become More Restrained in Public Law Cases?’ (2024) 87(5) MLR 1073. ↑

22. Case C-13/94 [1996] ECR I-02143 (holding that discrimination on the grounds of gender reassignment is sex discrimination). Views differ as to whether or not this case law was overwritten by the Equality Act’s ‘separation’ of the protected characteristic of sex discrimination from the protected characteristic of gender reassignment. For a comprehensive analysis of the applicable ‘missing’ European law, see Claire Bradley, ‘Why the FWS Case was Wrongly Decided by the UK Supreme Court – in Light of the EU Law Historical Context’ (EU Law Analysis Blog, 12 August 2025) <https://eulawanalysis.blogspot.com/2025/08/a-detailed-legal-analysis-which.html> accessed 30 June 2026. She argues that ‘for the Supreme Court to exclude all EU law when interpreting the Equality Act is incomprehensible, given that most of the Equality Act gives effect to obligations under EU law’. ↑

23. Semenya v Switzerland App no 10934/21. Note, though, that ultimately the Grand Chamber did not uphold this aspect of the Third Chamber judgment, since it found a violation only in respect of Semenya’s procedural rights, because Switzerland had no jurisdiction to hear her substantive complaints of discrimination: Semenya v Switzerland [GC] App no 10934/21 (ECtHR, 10 July 2025). ↑

24. Goodwin v United Kingdom (2002) 35 EHRR 18. ↑

25. Amnesty International, ‘Amnesty International UK’s Third-Party Intervention in the Supreme Court Appeal of the Case of For Women Scotland v Scottish Ministers, Taking Place on 26th and 27th of November 2024’ (22 November 2024) <https://www.amnesty.org.uk/knowledge-hub/all-resources/amnesty-international-uks-third-party-intervention-supreme-court-appeal-case-women/> accessed 30 June 2026. In particular, see Amnesty International UK Written Intervention [2023] CSIH 37 <https://media.amnesty.org.uk/documents/UKSC202024.004220Written20Intervention20-20Amnesty20International2028as20_iparFZq.pdf> accessed 30 June 2026. ↑

26. Goodwin (n 24) para 82. See also para 100. ↑

27. Atrey (n 20) 380. ↑

28. ibid 381–90. ↑

29. John Gardner, ‘On the Ground of Her Sex(uality)’ (1998) 18 OJLS 167; Tarunabh Khaitan, A Theory of Discrimination Law (OUP 2015) 32; Atrey (n 20), citing Sandra Fredman, Discrimination Law (3rd edn, OUP 2022) 206. ↑

30. Wigley (n 20). For discussion of the substance of the current Code as it applies to trans people’s equality rights, see Sharon Cowan and others, ‘Sex and Gender Equality Law and Policy: A Response To Murray, Hunter Blackburn and MacKenzie’ (2021) 30(1) Scottish Affairs 74–95. ↑

31. R (Hurley) v Secretary of State for Business, Innovation and Skills [2012] EWHC 201 (Admin), which speaks at paragraph 77 of the need for ‘a rigorous consideration of the duty, so that there is a proper appreciation of the potential impact of the decision on equality objectives and the desirability of promoting them’. ↑

32. Hannaford (n 20) 99–104. ↑

33. Cowan and others (n 30). ↑

34. Southampton ET/1400244/2014. ↑

35. This judicial notice extends only to childcare, not to other forms of social care such as caring for elderly or disabled relatives. ↑

36. Robert Mullins, ‘For Women Scotland: Fastening the “biological” straitjacket’ (UK Constitutional Law Association Blog, 2025) <https://ukconstitutionallaw.org/2025/05/22/robert-mullins-for-women-scotland-fastening-the-biological-straitjacket/> accessed 30 June 2026. ↑

37. Medics at the British Medical Association’s (BMA) resident doctors conference in London in 2025 passed a motion stating that ‘attempting to impose a rigid binary has no basis in science or medicine’: Libby Brooks, ‘UK’s First Trans Judge Appeals to European Court of Human Rights over Supreme Court Ruling’ The Guardian (29 April 2025)

    <https://www.theguardian.com/society/2025/apr/29/uks-first-trans-judge-victoria-mccloud-appeals-to-european-court-over-supreme-court-ruling> accessed 30 June 2026. ↑

38. See, eg, Mullins (n 36). ↑

39. There have also been creative arts responses critiquing the decision, such as music, poetry and a parody alternative judgment. See, eg, Emily Grabham, ‘Parody Alternative Judgment: For Women Scotland [2025]’ (CLT, 1 May 2025) <https://criticallegalthinking.com/2025/05/01/parody-alternative-judgment-for-women-scotland-2025/> accessed 30 June 2026; SJ Cooper-Knock, ‘Equali-T’ (song, YouTube, 3 November 2025) <https://www.youtube.com/watch?v=3oYEAgZXW0M> accessed 30 June 2026. ↑

40. Hannaford (n 20) 95, citing For Women Scotland (n 4) para 240. ↑

41. Brooks (n 37). ↑

42. Equality and Human Rights Commission, Services, Public Functions and Associations Statutory Code of Practice (2011) <https://www.equalityhumanrights.com/equality/equality-act-2010/codes-practice/services-public-functions-and-associations-code-0> accessed 30 June 2026. At the time of writing the new Code has been laid before parliament but has not yet been approved by the Secretary of State: <https://www.equalityhumanrights.com/news/draft-services-code-practice-laid-parliament> accessed 30 June 2026. ↑

43. Simon McGarr has also queried whether the decision puts the UK at odds with EU Data Protection law: ‘Trans Rights are Data Rights’ (The Gist, 21 April 2025) <https://www.thegist.ie/the-gist-trans-rights-are-data-rights/> accessed 30 June 2026. ↑

44. Elizabeth Clery, ‘A Liberalisation in Attitudes?’ in Stuart Frankenburg, Elizabeth Clery and John Curtice (eds), British Social Attitudes: The 40th Report (National Centre for Social Research 2023) 4 <https://natcen.ac.uk/sites/default/files/2023-09/BSA%2040%20Moral%20issues.pdf> accessed 30 June 2026. ↑

45. UN Independent Expert on Protection against Violence and Discrimination Based on Sexual Orientation and Gender Identity, Country Visit to the United Kingdom of Great Britain and Northern Ireland (24 April – 5 May 2023) (OHCHR 2023) para 20 <https://www.ohchr.org/sites/default/files/documents/issues/sexualorientation/statements/eom-statement-UK-IE-SOGI-2023-05-10.pdf> accessed 30 June 2026. ↑

46. ibid para 27. ↑

47. Veronica Sanz, ‘No Way Out of the Binary: A Critical History of the Scientific Production of Sex’ (2017) 43(1) Signs: Journal of Women in Culture and Society 1, 3–4. See also Sonja Erikainen, Gender Verification and the Making of the Female Body in Sport: A History of the Present (Routledge 2019); Judith Butler, Who’s Afraid of Gender (Picador 2024) ch 9. ↑

48. Sanz (n 47) 12, 14. ↑

49. ibid 9. ↑

50. ‘The Rise of “EHRC Law”’ (Trans Legal Project, 22 June 2025) <https://www.translegalproject.org/post/the-rise-of-ehrc-law> accessed 30 June 2026. ↑

51. Butler (n 47) 135, 153. ↑

52. ibid 142–43. There is a healthy literature on sex, gender and the ‘real’, particularly in the Lacanian psychoanalytic tradition that I do not draw on here, but see, eg, Judith Butler, Gender Trouble (Routledge 1990) and Judith Butler, Bodies That Matter (Routledge 1993). ↑

53. Carol Bacchi, What’s the Problem Represented to Be? Analysing Policy Discourses (Pearson 2009). Bacchi asks this question in the context of policy, but it is equally relevant to legislative and judicial representations of problems. ↑

54. Alex Sharpe, ‘Will Gender Self-Declaration Undermine Women’s Rights and Lead to an Increase in Harms?’ (2020) 83(3) MLR 539. ↑

55. Gwenffrewi (n 18); Sara Ahmed, ‘Meaningless Sex: Some Thoughts on the Supreme Court, the EHRC and Other Feminist Dystopias’ (Feminist Killjoys, 29 April 2025) <https://feministkilljoys.substack.com/p/meaningless-sex> accessed 30 June 2026. ↑

56. See, eg, Hutchinson v County Durham and Darlington NHS Foundation Trust [2026] ET/2501192/2024 & others <https://www.judiciary.uk/wp-content/uploads/2026/01/Bethany-Hutchison-Others-v-County-Durham-and-Darlington-NHS-Foundation-Trust-2501192-24-Others-Reserved-judgment.pdf> accessed 30 June 2026. Also reported by the BBC: ‘Hospital “Regrets” Trans Nurse Row Distress’ (BBC News, 27 January 2026) <https://www.bbc.co.uk/news/articles/cqj2p7pe77zo> accessed 30 June 2026. ↑

57. Peggie (n 12). The tribunal held that NHS Fife had discriminated against Sandie Peggie in their treatment of the complaint made against her by Beth Upton. Reporting on this case is prolific, but see, eg, <https://www.bbc.co.uk/news/articles/cy8p41z972vo> accessed 30 June 2026. The tribunal rejected Beth Upton’s application for anonymity during the hearing, to avoid identification in reporting of the case, and also allowed the claimant and her representatives to refer to Beth throughout as ‘he’ and ‘him’ so long as it was not done ‘offensively’ or ‘gratuitously’. It is difficult to see how, in an open court of justice, persistent misgendering by legal actors of Upton – who was ultimately found by the tribunal to have been harassed by the claimant including through misgendering – could be anything other than offensive. ↑

58. See, eg, Smart (n 11). ↑

59. For further discussion, see Sally Hines, ‘Sex Wars and (Trans) Gender Panics: Identity and Body Politics in Contemporary UK Feminism’ (2020) 68(4) The Sociological Review 699. ↑

60. Corbett (n 5). For an in-depth discussion of the background to the case and the decision, see Stephen Gilmore, ‘Corbett v Corbett: Once a Man, Always a Man?’ in Stephen Gilmore, Jonathan Herring and Rebecca Probert (eds), Landmark Cases in Family Law (Hart Publishing 2011). However, as Gilmore explains at 101, the Scottish succession case of In Petition of John Alexander Cumnock Forbes-Sempill and the Honourable Ewan Forbes-Sempill was heard in the Court of Session three years prior to Corbett, with the presiding judge Lord Hunter describing chromosomal evidence as the ‘least valuable of the available criteria’. ↑

61. R v R [1991] UKHL 12, [1992] 1 AC 599 (HL). ↑

62. ibid, at 47, emphasis added. ↑

63. Hannaford (n 20) 85. ↑

64. Smart (n 11). ↑

65. Sanz (n 47) 23. ↑

66. Roger Henderson, ‘Sir Roger Ormrod’ (1992) 304 British Medical Journal 1172 <https://doi.org/10.1136/bmj.304.6835.1172>. ↑

67. Robin Dunn, ‘Ormrod, Sir Roger Fray Greenwood (1911–1992), judge’, Oxford Dictionary of National Biography (2004) <https://www.oxforddnb.com/view/10.1093/ref:odnb/9780198614128.001.0001/odnb-9780198614128-e-51268> accessed 30 June 2026. ↑

68. Edward Cazalet, ‘The Wit, Wisdom and Jurisprudence of Sir Roger Ormord’ (address to the Family Law Bar Association, 6 May 1988) <https://www.jsasoc.com/Family_archive/Archive/Roger%20Ormrod/edward%20cazalet%20appreciation.pdf> accessed 30 June 2026. ↑

69. ‘Sir Roger Ormrod’ The Times (9 January 1992) <www.jsasoc.com/Family_archive/Archive/Roger%20Ormrod/roger%20ormrod%20obit%20times.pdf> accessed 30 June 2026. ↑

70. Henderson (n 66). ↑

71. Roger Ormrod, ‘The Reform of Legal Education’ (1971) 5(2) The Law Teacher 77, 84. See also Roger Ormrod ‘The Developing Relations Between the Law and the Social Sciences’ (1963) 4 British Journal of Criminology 320; Roger Ormrod, ‘Evidence and Proof: Scientific and Legal’ (1972) 12(1) Medicine, Science and the Law 9; Roger Ormrod, ‘The Debate Between Psychiatry and the Law: The Forty-eighth Maudsley Lecture, delivered before the Royal College of Psychiatrists, 15 November 1974’ (1975) 127(3) The British Journal of Psychiatry 193. He also had a lecture published in Current Legal Problems in 1987, on judicial discretion in the Court of Appeal and House of Lords: Roger Ormrod, ‘Judicial Discretion’ (1987) 40(1) Current Legal Problems 123. ↑

72. See Gilmore (n 60), who also gives this as a reason as to why Corbett, as a first instance decision, has been given such status in subsequent case law. ↑

73. Forstater (n 14). ↑

74. For Women Scotland (n 4) para 54. ↑

75. Corbett (n 5) para 47. ↑

76. [1983] QB 1053 ↑

77. ibid 1064 (emphasis added). ↑

78. [2004] UKHL 21, para 52. ↑

79. Roger Ormrod, ‘The Medico-Legal Aspects of Sex Determination’ (1972) 40(3) Medico-Legal Journal 78, 78 <https://doi.org/10.1177/002581727204000302>. ↑

80. ibid. ↑

81. Joseph M Thompson, ‘Transsexualism and Access to a Child’ (1982) 8 Journal of Medical Ethics 72. ↑

82. Zoë Playdon, The Hidden Case of Ewan Forbes: And the Unwritten History of the Trans Experience (Bloomsbury 2021). See also Lesley-Anne Barnes, ‘Gender Identity and Scottish Law: The Legal Response to Transsexuality’ (2007) 11(2) Edinburgh Law Review 162. ↑

83. Ormrod (n 79) 88. ↑

84. For example, Lord Justice Thorpe in Bellinger v Bellinger [2001] EWCA Civ 1140. Indeed, the Inner House of the Court of Session in For Women Scotland stated that Corbett (and Bellinger) were now of limited application. For Women Scotland Ltd v The Scottish Ministers [2023] CSIH 37 (Inner House, Court of Session, Second Division, 1 November 2023), per Lady Dorrian, para 38. See also see Laura Grenfell, ‘Making Sex: Law’s Narratives of Sex, Gender and Identity’ (2003) 23(1) Legal Studies 66. ↑

85. See, eg, the campaign and lobby group Sex Matters, ‘Supreme Court Judgment: Summary and Practical Advice’ (21 April 2025) <https://sex-matters.org/posts/publications/supreme-court-judgment-summary-and-practical-advice/> accessed 30 June 2026; and the academic Michael Foran’s contributions: Michael Foran, ‘Sex Has Always Meant Biological Sex’ (Knowing Ius, 19 April 2025) <https://knowingius.org/p/sex-has-always-meant-biological-sex> accessed 30 June 2026; Michael Foran, ‘Human Rights, Gender Recognition and Single-Sex Spaces’ (UK Constitutional Law Association, 11 February 2026) <https://ukconstitutionallaw.org/2026/02/11/michael-foran-human-rights-gender-recognition-and-single-sex-spaces/> accessed 30 June 2026. ↑

86. Jemima Repo, The Biopolitics of Gender (Oxford University Press 2015). ↑

87. Davina Cooper and Flora Renz, ‘If the State Decertified Gender, What Might Happen to its Meaning and Value?’ (2016) 43(4) Journal of Law and Society 483. ↑

88. See, eg, the excellent Future of Legal Gender project, funded by the ESRC 2018-2022, which has produced many publications (<https://futureoflegalgender.kcl.ac.uk/>). ↑

89. Kendra Albert and Maggie Delano, ‘Sex Trouble: Common Pitfalls in Incorporating Sex/Gender in Medical Machine Learning and How to Avoid Them’ (2022) arXiv 08227 <https://doi.org/10.48550/arXiv.2203.08227>. ↑

90. Tanya Serisier, Speaking out! Feminism, Rape and Narrative Politics (Palgrave MacMillan 2018) 215. See also Sara Ahmed, The Cultural Politics of Emotion (Edinburgh University Press 2004). ↑