On 16 April 2025, the UK Supreme Court issued a ruling on the meaning of ‘sex’ in the Equality Act 2010 (EA), after a group called For Women Scotland challenged the Scottish Government’s interpretation of the Act. The Scottish Government had interpreted safeguards that are provided in the EA for the protected characteristic of ‘sex’ to include people who have legally changed their sex and hold a ‘gender recognition certificate’. The Supreme Court ruled that, for the purposes of the EA, ‘sex’ means only what they term ‘biological sex’. Initial reactions to this ruling, such as from the Equality and Human Rights Commission, suggest it could have far-reaching consequences for trans rights in the UK. Members of the Centre for the Study of Sexuality and Culture respond below to various aspects of the ruling, drawing on their research in gender and sexuality studies to do so. 

 

On Sex and Gender

To understand how the Supreme Court ruling has legitimised the idea that trans women ‘are’ ‘biological men’, and trans men ‘biological women’, it’s helpful to look at the way the judgment positions transition as a process of ‘gender reassignment’ that leaves ‘sex’ unchanged for the purposes of the Equality Act. The distinction between sex and gender is often assumed to be a useful tool for explaining transness: we commonly hear, for example, that a trans person is anybody whose ‘gender identity’ differs from their ‘sex assigned at birth’. In the judgement and in its interpretation by the Equality and Human Rights Commission, however, the notion that sex is immutable even if gender is variable has the effect of erasing the efficacy of transition. Those with the protected characteristic of ‘gender reassignment’ are produced as a class unto themselves. In the language of anti-transness, they are now ‘trans-identified’, rather than people who have become men, or people who have become women.

 

How did we get here? ‘Sex’ used to be transition’s ordinary organising term. By this we just mean that it was via the category of ‘sex’ that transition was imagined – hence the 1980 BBC documentary about Julia Grant, A Change of Sex, in which the word ‘gender’ is rarely used. It’s spoken once or twice by the psychiatrist Dr John Randall, which hints at its clinical history: the use of the term ‘gender’ to signify the social or cultural dimensions of sex first emerged in the mid-century thinking of John Money and Robert Stoller, who worked with intersexuals and transsexuals respectively. Before then, ‘gender’ was mainly a linguistic term for grammatical relations between words. At the outset of the 1970s, Money and Stoller’s ideas were picked up and reworked by feminists such as Ann Oakley, the British sociologist, and Kate Millett, a literary critic for whom ‘gender’ helped to name the associations and expectations patriarchal society superimposes on sexual differences between females and males. Millett also suggested that gendered life might sometimes have skewed our sense of what those sexual differences are. 

 

The uptake of ‘gender’ was initially uneven – only a few feminist texts used the word in the first half of the 1970s – but the concept became a powerfully generative site of feminist thought. Nevertheless, terms like ‘sex role’ and ‘sexual identity’, which used to mean something more like gender expression than sexual orientation, continued to be used into the 1980s by feminists and trans people alike. Black feminists such as Hortense Spillers showed that the sex-gender distinction was a racial arrangement by pointing out how gender as a vector of familial inheritance was refused to the enslaved. In the 1990s, the term ‘transgender’ started to circulate, gradually overtaking ‘transsexual’ as the preferred term of many Western trans people and, following its adoption by institutions, helping to popularise Stoller’s distinction between sex and ‘gender identity’ – a person’s own sense of themselves as sexed – as a way of explaining what a trans person was. The academic humanities were animated by discussion of gender. Sex, a category that was once as much social as biological – just look up the word in a nineteenth-century realist novel – was increasingly, though not exclusively, left to the scientists.

 

The Supreme Court states that it is not its role to adjudicate on the meanings of sex and gender in the public domain. Yet it would nonetheless seem that a version of the sex-gender distinction has implicitly informed their decision: the version of Sex Matters, for whom sex is an unalterable fact, gender a fanciful notion that seeks to deny or conceal sexual reality, rather than, as 1970s feminists suggested, reveal the ways in which reality is shaped by relations of power. At the same time, gender and sex are still used interchangeably, as they are in the Gender Recognition Act: the judgement speaks of both ‘acquired gender’ and ‘acquired sex’ and somewhat begrudgingly grants sexual biology a limited mutability when it acknowledges that transition may involve ‘a change in physiological or other attributes of what must necessarily be biological sex [my emphasis]’ (para 200). Ultimately, the judgement decides it is feasible to assign women rights based on ‘sex’, trans people rights based on ‘gender reassignment’. In doing so, however, it excises the efficacy of transition, even as it admits to the possibility that biological sex can be modified. 

 

Indeed, by exempting sex and gender from history – from the social and political forces that have informed their meanings – we risk collectively forgetting that ‘sex itself’ is a site of change: in the words of feminist historian of science Sarah Richardson, ‘a history of contestations’. 

 

Suggested Readings

Germon, Jennifer. 2009. Gender: A Genealogy of an Idea. New York: Palgrave MacMillan.

Lavery, Grace. Pleasure and Efficacy. On Pen Names, Cover Versions, and Other Trans Techniques. 2023. Princeton, New Jersey: Princeton University Press.

Millett, Kate. 1970. Sexual Politics. Urbana and Chicago: University of Illinois Press.

Oakley, Ann. 1972. Sex, Gender and Society. London: Temple Smith.

Richardson, Sarah S. 2013. Sex Itself: The Search for Male and Female in the Human Genome. Chicago and London: University of Chicago Press.

Spillers, Hortense. 1987.  “Mama’s Baby, Papa’s Maybe: An American Grammar Book.” Diacritics, 17, No 2: 64-81

Wilson, Ara. 2021. “Gender Before the Gender Turn.” Diacritics 49, no. 1: 13-39

 

On the Biological

One of the founding maxims of second-wave feminism was Simone de Beauvoir’s widely cited phrase from The Second Sex (1949): ‘one is not born, but rather becomes, a woman’ (p. 293). As Beauvoir writes: ‘If her functioning as a female is not enough to define woman, if we decline also to explain her through the “eternal feminine”, and if we nevertheless admit, provisionally, that women do exist, then we must face the question: what is a woman?’ (p. 4-5). To answer this question through the prism of becoming is to draw attention to the multiple ways this category is socially produced and lived in different historical and cultural contexts – varying both between those bodies named by it and within one embodiment across a lifetime. For Beauvoir, the answer to this question cannot be found in biology, since biology is not simply a set of determining ‘data’; rather, it is a contested field of knowledge about living things that has continued to evolve since the early nineteenth century (Foucault, 1970). As Beauvoir argues: biology is not irrelevant; but neither is it destiny.  

 

Becoming a woman requires navigating a set of deep-seated social expectations and prohibitions. Since the 1970s, feminists have rejected the institutionalisation of biological determinism that has justified prejudicial assumptions about women’s inferiority. In 1977, the Combahee River Collective stated that ‘any type of biological determinism’ is a ‘dangerous and reactionary basis on which to build a politic’. Since then, Black feminists have repeatedly demonstrated how naturalised definitions of ‘womanhood’ mobilise racial and class inequalities and idealise white, middle-class femininity (Lewis, 2018). The language of biology disguises the prescriptiveness of changing cultural norms. For example, the UK’s Football Association banned women between 1921 and 1971 (purportedly because their breasts would get in the way); yet in 2022, the Lionesses were celebrated as UEFA champions. If a woman were merely a self-evident biological category, how could we account for the profound changes across the centuries and generations in terms of how she looks, acts, labours and desires?

 

So how has this language entered legal and regulatory discourses to redefine the categories of ‘sex’, ‘woman’, ‘man’ in ways that are currently curtailing the established rights of trans people in the UK to access public facilities, to receive appropriate medical care and to live with dignity? 

 

The 2025 Supreme Court ruling and the subsequent Equality and Human Rights Commission interim guidance, each adopted the term ‘biological sex’, without ever defining it. As if it were merely a set of data, the Supreme Court mobilised biology to exclude trans women as women from the Equality Act. In a letter to Rt. Hon. Bridget Phillipson, a group of biologists and doctors have subsequently criticised this strict binary definition of sex, rejecting it as ‘an over-simplification … not capable of capturing biological diversity present in human populations’, and concluding therefore that this is ‘an unsafe basis for policy’ (emphasis in original). Rather than being determined by one phenomenon, they argue, ‘sex’ refers to several different biological elements, including: ‘external genitalia, gonads, chromosomes, hormones, and secondary sex characteristics’. Similarly, on 28 April, the resident doctors’ wing of the BMA passed a conference motion declaring that to impose a binary definition on either sex or gender ‘has no basis in science or medicine, while being actively harmful to transgender and gender-diverse people’; they dubbed the ruling ‘biologically nonsensical’ and ‘scientifically illiterate’. As these protests make clear, it is wrong-headed and misleading to define the category woman legally through an appeal to the biological as self-evident data, which it is not.

 

 

In 1988, Section 28 of the Local Government Act naturalised the heterosexual family to prohibit any state-funded ‘promotion of homosexuality as a pretended family relationship’ (emphasis added). In hindsight, this law is widely regarded by all political parties as unjust and discriminatory, designed to humiliate and segregate. The homophobic media coverage of Section 28 represented lesbians and gays as ‘having gone too far’ in wanting more than simply to be quietly tolerated. The parallels with the transphobia currently circulating widely in media and public debates are striking. It remains to be seen how history will judge this moment. 

 

Suggested Readings

Combahee River Collective. 1977. 

https://www.blackpast.org/african-american-history/combahee-river-collective-statement-1977/

de Beauvoir, Simone. 2010 [first published 1949, first translated in 1953] The Second Sex, trans. by Constance Borde and Sheila Malovaney-Chevallier. London: Vintage. 

Foucault, Michel. 2018  [first published in translation 1970] The Order of Things. London: Routledge.

Lewis, Gail. 2009. ‘Birthing Racial Difference: Conversations with my Mother and Others’. Studies in the Maternal, 1:1, pp. 1-21.

Riley, Denise. 1988. Am I that Name? Feminism and the Category of ‘Women’ in History. London: Palgrave Macmillan.

Scott, Joan W. 2013. ‘The Uses and Abuses of Gender’. Tijdscrift voor Genderstudies. Nr 1. pp. 63-77.

 

On Common Sense

A number of media responses to the UK supreme court’s recent ruling on the meaning of “sex” in the Equality Act 2010 claimed it as a victory for “common sense”. Such responses take it for granted that there is a simple meaning to words like sex, woman, and man and express relief that we can finally just let them mean what we “know” they all mean. While the authors of the ruling stopped short of calling it “common sense”, they nonetheless presented it in terms of similar kinds of unquestioned certainty: what is “clear”, “unambiguous”, “objective”, “reasonable”, “sensible”, “plainly intended” or in the “ordinary meaning of the words used”.

 

But for decades scholars have questioned the belief in certainty like this—in ideas or positions that are seemingly so clear as to be unquestionable. Scholars like Antonio Gramsci, Stuart Hall, Clifford Geertz and, more recently, Sara Ahmed have in various ways argued that what passes for “common sense” is in fact a set of values that have come to seem normal and eternal, but are actually rooted in the biases of their particular historical moment. We only have to look at how ideas that might previously have seemed like common sense no longer do—ideas about race, or marriage or disability—to see that “common sense” is not a stable and unchanging basis for reasoning.

 

The judgment itself implicitly seems to suggest that what is plain or obvious might not be quite so straightforward insofar as it requires more than 80 pages of complex, technical legal argument in order to establish what is supposedly unambiguous. Indeed, if the express purpose of the judgment is to ascertain the intended meaning of terms in the Equality Act, one might argue that a more obvious or “common sense” approach would be to consult someone who was closely involved in drafting it. For example, Melanie Field, the senior civil servant who oversaw the writing of the Act, has been clear that Parliament’s intention at the time was to give trans people with gender recognition certificates the same sex discrimination protections as those living in their gender assigned at birth. The supreme court therefore has issued a judgment that goes against what was “plainly intended”.

 

What emerges through the judgment is that what seems plain or obvious to the Justices actually reveals that they take a very particular (and not necessarily “common”) approach. For example, part of their reasoning for why a “biological” definition of sex is the only one that makes sense is because, if a broader definition were to be adopted, this would create a category “woman” that includes trans women and this would be “a confusing group to envisage” (para 239). This is because there would apparently be nothing that unites this group: no “shared biology leading to shared disadvantage and discrimination faced by them as a distinct group” (para 172). Here, they can only imagine a group united by a narrow vision of biology, yet elsewhere they recognise that groups are constituted by “societal expectations or structures affecting their group” (para 153). This latter point is more in line with some feminist scholars who have argued that women as a group are constituted by their social position within patriarchy and by their shared vulnerability to patriarchal violence, rather than by biology. Indeed, it would be hard to see how trans women do not share this vulnerability and do not also have need to access some of the “single-sex” services that the judgment believes they should have no automatic right to access: rape crisis centres, domestic violence refuges and related counselling services, amongst others. Rather than expressing a general common sense, the Justices’ view betrays a deep biological determinism, an easily questioned belief that what unites women or gives them coherence as a group is some kind of shared biology (exactly what biology is shared is unspecified). 

 

What is plain to see is that what passes for common sense changes over time. Rather than appeal simply to what is apparently clear, obvious and unambiguous, surely it’s more helpful to interrogate what makes a given idea seem unquestionable and think about whose interests are served in the process. 

 

Suggested Readings  

Ahmed, Sara. 2023. ‘Common Sense as a Legacy Project’. Feminist Killjoys blog <https://feministkilljoys.com/2023/05/30/common-sense-as-a-legacy-project/> 

Geertz, Clifford. 1975. ‘Common Sense as a Cultural System’. Antioch Review 33, no. 1: 5-26

Hall, Stuart et al. 1978. Policing the Crisis: Mugging, the State, and Law and Order. London: Macmillan

Mackinnon, Catherine A. 2023. ‘Exploring Transgender Law and Politics’, ‘Feminist Frictions: Key Concepts and Controversies’, Signs Journal <https://signsjournal.org/exploring-transgender-law-and-politics/> 

 

Where Next? On Ordinariness

At a time of such intense hostility towards trans people, it may seem odd to talk about ordinariness. Rightly, many people have pointed out that trans people make up a tiny minority of the population. Yet it also seems important to remember that everybody has a relationship to sex and gender. Everybody, moreover, experiences some form of sexual change during their lifetime: puberty, menopause, lowering testosterone levels. Sexual change is ordinary, but its different forms lead to particular needs. Menopause is routinely treated with HRT, for example. Every human being carries the genetic information that could lead to the development of male and female secondary sexual characteristics: our chromosomes condition the hormonal environment that influences those characteristics’ development, but hormones change, leading to alterations in how our genes are expressed. Those whose lives move them towards transition, whatever form it may take, are no less worthy of respect and appropriate care than anybody else, and as Henry Rubin suggested, they, we, have the right to desire ordinariness too – to go about our everyday lives ‘unmarked by suspicion and hostilities’. 

 

Dr Gareth Gavin, Professor Jackie Stacey, Dr Ben Nichols

Centre for the Study of Sexuality and Culture

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