While public attention has been fixed on the repercussions of the For Women Scotland Supreme Court judgment and growing restrictions on the right of trans children and young people to transition, an insidious and existential threat to the future of the trans community has been working its way into the very core of the UK Government.
Like other forms of anti-trans activism, it cloaks itself in the language of ‘biological reality’ and ‘common sense’ while pursuing its discriminatory and ideological ends. But unlike more visible flashpoints –healthcare, education, the workplace – it is further concealed by its apparent technicality and presumed impenetrability.
In this obscurity, trans-exclusionary data activism (TEDA) has, over the past decade, gained considerable ground. Its impacts are deeply consequential yet often unrecognised: essentialising the category of ‘sex’, delegitimising ‘gender’, and pushing trans, nonbinary, and intersex people into the statistical shadows – where they can be dismissed as aberrations or maligned as corruptions of otherwise healthy data.
Two recent peer-reviewed articles – Kevin Guyan’s Trans-exclusionary data activism in the UK and A Critical Response to the UK’s “Sullivan Review” Into Sex and Gender in Research and Data by Jay JD Todd and Felicity Callard – highlight both the methods and the consequences of TEDA. Guyan defines it as a movement with shared tactics and goals; Todd and Callard examine its most ambitious institutional expression to date: the UK Government-commissioned review of sex and gender data, better known as the Sullivan Review.
The Sullivan Review
The Sullivan Review is an ideal case study for TEDA. It exemplifies what Guyan describes as “the invention of a problem [that] invites a solution”. Against the backdrop of a political push to “[kick] woke ideology out of science”, sociologist Alice Sullivan – a member of the anti-trans campaign group Sex Matters’ advisory board – was tasked by the Conservative Government with leading a review intended to shape data practices across all areas of government and publicly-funded research.
As Todd and Felicity reveal in their critique of the review, it follows the TEDA playbook closely. Born out of a manufactured controversy, it advances an absolutist, ‘biology-first’ approach centred on sex assigned at birth. It treats sex as binary and immutable, arguing that allowing self-identification or more inclusive categories (for example, to accommodate intersex people) undermines “clarity”.
In doing so, the review misrepresents scientific and medical consensus on the complexity of sex and gender, dismisses the value of community input in question design, and promotes survey methods that steer respondents towards anti-trans framings.
Yet these approaches are also likely to produce – simply put – bad data. Survey researchers have long recognised that respondents answer questions according to how they interpret them, not according to the survey designer’s preferred definitions. Forcing respondents to engage with a rigid and contested idea of “biological sex” is therefore likely to result in inconsistent and unreliable answers.
The review further advocates a one-size-fits-all model across all domains of data collection and calls for reduced oversight from research ethics committees. This runs roughshod over the careful, context-specific decisions researchers must make about what data is relevant and ethical to collect in light of their research objectives.
Already, the Sullivan Review has been used to shape government data policy. Following the review, the Government Statistical Service (GSS) announced plans to develop harmonised standards on sex and gender identity. At the same time, the Secretary of State for Health and Social Care instructed the health service to immediately suspend applications from under-18s to change the sex marker on their medical records.
If national data policy continues to be influenced by the Sullivan Review, the consequences are clear: the effective erasure of trans, intersex, and gender-diverse people from official data, alongside heightened risks of outing, harassment, and discrimination when accessing public services.
TEDA Creep
Since the publication of the Sullivan Review, TEDA militants have gained traction in pushing overly simplistic approaches to sex and gender data across multiple domains.
During deliberations on the Data (Use and Access) Bill, several amendments – supported by anti-trans pressure groups – were aimed at mandating that all past and future records held by UK public authorities reflected “sex at birth” only. This would have meant that businesses, employers, landlords, etc. would have been able to out virtually any person they suspected of being trans through routine identity checks using digital verification systems.
While these amendments failed, the broader strategy has not shifted. TEDA actors continue to target key data infrastructure, pursuing a dual objective: erasing trans people in some contexts, while hypervisibilising them in others.
The Office for National Statistics’ inclusion of a gender identity question in the 2021 Census marked a significant step forward. Yet following complaints from TEDA activists, the resulting data – potentially the most robust estimate of the UK’s trans population – lost its official accreditation. Looking ahead, the ONS consultation on the Census 2031, alongside the ongoing harmonisation work underway by the GSS, will facilitate further infiltration of TEDA viewpoints.
The proposed digital ID scheme has become another focal point. Since its announcement in September 2025, groups such as Sex Matters have argued that digital ID should include sex assigned at birth, citing concerns about “inaccurate” forms of identity like passports that supposedly “mix” sex and gender identity. They even provide illustrative examples of how this Digital ID data could be used; revealing how, in the dystopian future of their wildest dreams, your sex assigned at birth would be scrutinised at every turn: Renting in a shared flat. Joining a gym. Applying for a job. Even signing up for a dating service.
Most recently, spurred on by the For Women Scotland Supreme Court judgment, the Government Equality Office updated its guidance on gender pay gap reporting to recommend employers take steps to ascertain all employees’ “biological sex” by taking “proportionate” action if they suspect sex data they already have to be “unreliable”. What this proportionate action looks like is not specified, so we can only imagine that some HR departments will begin to operate like amateur transvestigation bureaus.
In this way, enabled by broader anti-trans developments, the TEDA agenda continues to extend its shadowy claws deeper and deeper into our everyday lives.
Human Rights Considerations
Articles highlighting the threat of TEDA come at a time of growing awareness of and resistance to panoptic government surveillance, with resistance to compulsory digital ID so great that the government reversed course on its being mandatory after a UK Parliament petition received 2.9 million signatures.
It is therefore clear there is great public support for affirming individuals`right to privacy as one of the most fundamental human rights. These rights are protected under Article 12 of the Universal Declaration of Human Rights, Article 8 of the European Convention on Human Rights, Article 17 of the International Covenant on Civil and Political Rights, and the UK General Data Protection Regulation. The Gender Recognition Act 2004 goes beyond this to provide additional safeguards against the disclosure of a trans person’s gender history.
For this reason, it is deeply troubling that TEDA actors increasingly advocate for an approach to data that would normalise the intrusive interrogation of people’s sex – at times necessitating the scraping of data from medical and civil records like birth certificates – without any clear rationale or tangible benefit to society beyond the conviction of a vocal and obstinate few that, contrary to scientific consensus, sex is immutable, binary, and should be privileged over the complexities of lived reality.
The Biopolitics of TEDA
TEDA operates behind the scenes intentionally. Its proponents aim to conceal their work behind the common belief that how we collect data is a technical, bureaucratic preoccupation. But TEDA’s effects are not to be underestimated. By reshaping how data is collected and interpreted, it quietly influences who is counted, how they are understood by public institutions, and whether they are able to legitimately affirm their human rights.
On a more personal level, it shapes how people understand us, how they treat us. It also affects how we understand and treat ourselves.
Crucially, this is not only a threat to trans, intersex, and gender-diverse people. An approach to data that distrusts self-identification and privileges a researcher’s authority over one`s personal identity has far-reaching implications. It sets a precedent that could reshape how all forms of identity data are collected – affecting other categories that rely even partially on self-identification, such as sexual orientation or ethnicity.
Resisting TEDA therefore requires more than technical critique of its harmful methodologies – though that is an essential place to start. It demands that our society grapples with the real existential threats to all marginalised peoples of unethical data practices run amok.
To divert briefly into the philosophical – in Foucauldian terms, we might understand this as a struggle over classification as a tool for the production of ‘truth’ itself; over who gets to define the categories through which life is made visible, and on what terms. These categories are not neutral or natural at all – they are produced by and embedded in the systems that govern us.
We must resist efforts to concentrate more power over our identities into administrative systems of biopolitical management, where people are reduced to increasingly narrow categories optimised for bureaucratic convenience over lived reality. We must continue to educate ourselves about the ways classification can be used to control us – the book Rainbow Trap by Kevin Guyan is a good place to start – and we must write to our political representatives urging them to resist movements like TEDA that seek to weaponise data against marginalised communities.
By taking action in this way, we not only affirm our right to self-articulation, we also increase our very capacity for self-determination.