After years of campaigning “to promote clarity about sex in law, policy and language in order to protect everybody’s rights”, Sex Matters finally achieved “clarity” on the definition of sex in the Equality Act 2010 (EA2010). The supreme court ruled that in the EA2010 – the UK’s most significant piece of equalities legislation – “sex” referred to “biological sex” (sex recorded at birth) only, and did not include sex as amended by a gender recognition certificate (GRC).
This ruling was initially welcomed by many, including Keir Starmer, the prime minister, and women and equalities minister Bridget Phillipson. Many of those who supported the court’s decision appeared to believe it would draw a line under “toxic” debates, and settle disputes, not escalate them. And why wouldn’t they? After all, Sex Matters had explained that defining sex in this way would “make clear that single-sex services, accommodation, associations, charities and sports are allowed”, while “not remov[ing] protection against discrimination for transgender people, because ‘gender reassignment’ is a separate protected characteristic from sex”.
Who would argue against that?
Inclusivity changes have followed
Yet, fast forward nine months, and we have seen trans people banned overnight from the trans-inclusive services, facilities and organisations they have used without harm for decades. After years of inclusion, the Women’s Institute and Girlguiding announced that they would no longer be able to accept trans women or girls as members. Trans women are to be newly banned from the main 2026 Labour Women’s Conference, while Kenwood ladies’ pond, whose members voted democratically in 2024 to remain trans-inclusive with recent overwhelming support from the public, has faced legal threats (from Sex Matters) to exclude all trans women.
In other words, providers and organisations are being told they can no longer be trans-inclusive, even if they and their members want to. This post-ruling interpretation sits uneasily with the statements of Lord Hodge, the supreme court justice who presided over the case, who “pointed out that the case before the court had nothing to do with how or where single-sex spaces should be created” since “[t]hese points weren’t argued before us”. While some legal challenges to trans inclusion have to date thankfully failed, faced with the threat of costly legal action, regulatory pressure, hostile guidance, negative articles in right-wing news media and social media pile-ons, many other organisations have simply ‘obeyed in advance’ and chosen exclusion as the ‘safest’ option.
Misapplication of terms
At the same time, the supreme court’s “biological” definition of “sex” (which applies specifically and only to the statutory interpretation of the EA2010) is now being arbitrarily pushed into other unrelated pieces of legislation, such as Scotland’s hate crime and public order bill or the Workplace Regulations 1992. This after-the-fact expansion of the court’s definition rides roughshod over the fact that, under the Gender Recognition Act 2004, a GRC still changes a person’s legal sex “for all purposes”, unless a clear exception is made.
There has been a surge in the terms “biological man” (or “biological woman”) being shoehorned into media reporting about trans women or trans men respectively. This is despite the supreme court explicitly noting (para 2) that: “It is not the role of the court to adjudicate on the arguments in the public domain on the meaning of gender or sex, nor is it to define the meaning of the word ‘woman’ other than when it is used in the provisions of the EA 2010.”
Where does this come from?
Where has this transphobic media terminology bubbled up from? Perhaps this letter from Sex Matters to the BBC can shed some light, as it rails (incorrectly) that “The law recognises that men can never become women. No-one needs to say, write or pretend that they can.”
It’s worth noting that Sex Matters’ denial of personal, legal and social identities is extended in this letter not just to trans people, but also to those with intersex variations or even just women with elevated testosterone profiles, as Sex Matters summarily dismisses athletes Caster Semenya and Barbra Banda as “men”.
Reading Sex Matters’ letter to the BBC in full gives a sense of the viciousness of its objections to what it refers to as “the oppressive influence of transgender ideology”, the “controlling hand of the BBC’s LBGT [sic] and identity team”, and the “over-representation of individuals with a transgender identity”, which they dismiss as no more than a “minority belief system”.
Nonetheless, the BBC seems to have happily adopted Sex Matters’ position without question or consultation, with leaked guidance indicating that BBC journalists are now expected to describe trans women as “biological males”, and with the BBC claiming (like Sex Matters) this is required for clarity, regardless of how trans+ people might experience such terms.
The right to live authentically
I have flagged Sex Matters’ attempt in April 2025 to use the supreme court ruling as a reason to halt the planned NHS puberty blocker trial. Rather than quietly dropping this bizarre line of argument, in a letter to Wes Streeting in November, it doubled down on this retroactive justification, arguing that “Following For Women Scotland, it is no longer tenable for a clinician to offer a treatment pathway intended to enable a child to grow up to live as a member of the opposite sex ‘for all purposes’.”
CEO of Sex Matters, Maya Forstater, went as far as to suggest that trans pupils should be forcibly outed when using school toilet facilities, arguing that efforts to respect a trans child’s identity and protect their privacy would not be in their “best interests, since it will only worsen the child’s dissociation from the unchangeable physical reality of their sex”. This claim has absolutely no legal or scientific basis, but disturbingly echoes the Heritage Foundation’s pseudoscientific language of “reconcil[ing] with their biological sex”. The National Union of Students has flagged how such forced outing would likely result in increased isolation, school avoidance, discrimination and distress.
The right to healthcare
And yet, Forstater’s claim fits with Sex Matters’ increasingly bold and bizarre statements on trans healthcare in general. Initially, Sex Matters appeared to welcome the 2024 Cass Review of gender identity services for children and young people, with its emphasis on “the importance of building a better evidence base” (p.6). And yet Sex Matters is now directly opposing attempts to build that evidence base, by calling for the planned PATHWAYS puberty blocker trial (recommended by Cass) to be scrapped.
Maybe this is unsurprising, given that Sex Matters has previously referred to gender-affirming care for trans children and young people as the “fastest-growing and most brutal form of conversion”. Echoing the careful playbook of Sex Matters’ director of advocacy Helen Joyce, this topsy-turvy crusade is now being extended to target adult healthcare, with Sex Matters also referring to evidence-based care for transgender adults as “state-sponsored conversion therapy”. At the same time, it strenuously opposes the government’s planned trans-inclusive ban on actual conversion practices – a ban that has been called for by the Parliamentary Assembly of the Council of Europe, and has the support of multiple international human rights experts as well as the UK’s leading healthcare bodies.
So much for clarity. So much for the preservation of trans people’s rights.
Power and influence
You might think that this increasingly ‘masks-off’ extremism would make those with influence and authority more wary of engaging with a group like Sex Matters – especially given that it has recently been revealed that Sex Matters is currently under investigation by the Charity Commission.
And yet, last September, Keir Starmer was happy enough to appoint Sex Matters (ex-) trustee Tim Allan as his new executive director of communications. And barely a week after the new chair of the Equality and Human Rights Commission (EHRC), Dr Mary-Ann Stephenson, took up her post on 1 December, she reached out to Sex Matters for a meeting to discuss their “mutual priorities”. This appears, at best, to indicate a shocking lack of due diligence and, at worst, an indication that Starmer or Stephenson take little issue with the extremes of Sex Matters’ agenda.
And yet, perhaps some are waking up to the fact that Sex Matters is not quite what it has seemed. Recently, health and social care secretary, Wes Streeting, expressed surprise that gender-critical MPs were now objecting to the planned puberty blocker trial. Despite explicit public lobbying in the mainstream media by the outgoing EHRC chair Baroness Kishwer Falkner, equalities minister Bridget Phillipson has still not approved the EHRC’s new code of practice (which sets out mandatory, blanket bans of trans people from gender-aligned services). Instead, Phillipson chose to intervene in the ongoing judicial review of the EHRC’s position with a submission that outlines arguments for how trans inclusion might still be possible. (Sex Matters, unsurprisingly, intervened to argue that trans exclusion is a must).
The price of appeasement
Perhaps some are starting to realise that supporting Sex Matters’ position has entangled them in something they never intended to sign up for. Appeasement does not moderate or halt them; it only shifts the Overton window, until those seeking compromise find they have surrendered nearly everything they once stood for — look at what Starmer has achieved by trying to compromise with Trump.
In trying to accommodate the “reasonable concerns” of those like Sex Matters, the UK has tumbled from first place to 22nd on the ILGA Europe Rainbow Map. There is alarm and condemnation from multiple international human rights bodies, including the Commissioner for Human Rights of the Council of Europeand 18 UN independent experts. Trans people are literally looking to flee the UK.
Meanwhile, Sex Matters is looking to extend its reach far beyond the UK, intervening in a supreme court case in the US, and supporting the efforts of the recently-formed Athena Forum, a gender-critical group explicitly established to protest the progress of trans rights and protections in Europe.
I stand by my previous claim that Sex Matters’ true agenda is eliminationist. What was framed as clarity has in truth enabled an ever-widening set of exclusions, with no indication that the demands, nor the impacts, will stop here.
Now is the moment to wake up and step back. The UK has given Sex Matters an inch, it’s taken a mile, but it’s not (yet) too late to get off the ride.
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