The evidence dossiers

Eleven British subjects, each built the same way: key facts with dates, the background, what the documents say, the positions of the parties, this site's reading marked as interpretation, and the open questions. Sources are listed and linked at the foot of every dossier.

The Cass Review: findings and recommendations

What did the Cass Review find about youth gender medicine in England, and what did it recommend?

The Cass Review was commissioned by NHS England after serious concerns emerged about the capacity, clinical model and evidence base of the national service for children and young people presenting with gender-related distress. For many years, the Tavistock’s Gender Identity Development Service, usually known as GIDS, was the sole national NHS specialist service in England. Referrals rose sharply and the profile of those referred changed substantially, with a marked increase in adolescent girls and young people with complex mental-health, neurodevelopmental and safeguarding needs.

Tavistock GIDS: rise, whistleblowers and closure

How did the Gender Identity Development Service grow, who raised the alarm, and why was it closed?

The Gender Identity Development Service (GIDS), run by the Tavistock and Portman NHS Foundation Trust, was for many years England’s sole national specialist service for children and young people experiencing gender-related distress. Its centralised structure meant that referrals from across England, and at points from other UK nations, were channelled towards one provider and associated satellite clinics.

For Women Scotland and the meaning of sex in the Equality Act

What did the UK Supreme Court decide in April 2025 about the meaning of sex, and what follows for single-sex services?

De zaak van For Women Scotland draaide formeel niet om toiletten, kleedkamers of ziekenhuisafdelingen. Zij ging over de vraag wie als “woman” telt bij het streven naar een betere vertegenwoordiging van vrouwen op Schotse publieke besturen. Maar de juridische vraag was veel breder: wat betekenen de woorden “sex”, “man” en “woman” in de Equality Act 2010, gezien section 9 van de Gender Recognition Act 2004?

The UK conversion-practices ban and exploratory therapy

Why have successive UK governments struggled to draft a conversion-practices ban, and what would it mean for therapists?

Successive UK governments have struggled to legislate because there is broad agreement on one proposition but sharp disagreement on another. Few dispute that violence, threats, coercion, forced confinement, assault, sexual abuse, forced marriage, exorcism involving abuse, or attempts to compel a person to renounce same-sex attraction should be prohibited. Much of that conduct is already criminal under existing law. The difficult question is whether, and how, criminal law should regulate conversations, counselling, prayer, family pressure and therapeutic work concerning sexuality or gender iden

Schools guidance on gender-questioning children in England

What has the Department for Education told schools about social transition, and what is the legal position?

For several years, English schools have faced competing requests and duties when a child says that they wish to be treated as the opposite sex, changes their name or pronouns, or seeks access to opposite-sex facilities. The Department for Education’s answer has now moved from proposed non-statutory guidance to safeguarding guidance which schools and colleges must have regard to.

Keira Bell, Bell v Tavistock and detransition in the UK

What did the Bell v Tavistock litigation decide, and what is known about detransition in Britain?

Keira Bell became the public face of a legal challenge to the former Tavistock and Portman NHS Foundation Trust’s Gender Identity Development Service (GIDS). Bell had received puberty-suppressing medication as an adolescent, later took testosterone and underwent surgery, and subsequently detransitioned. Together with “Mrs A”, the mother of a teenage girl, she sought judicial review of the lawfulness of the consent arrangements used when children and young people were referred for puberty blockers.

Single-sex spaces and women's sport in the UK

How do UK law and British sporting bodies handle single-sex provision and male inclusion in female sport?

The UK has never had a single, uniform rule requiring every sporting body to organise competition by sex in exactly the same way. Instead, Parliament created a legal framework in the Equality Act 2010, while national governing bodies decide how that framework applies to the physical demands, contact risks, competitive level and practical structure of their own sports.

Gender-critical belief, Forstater and free speech

How did Forstater v CGD Europe protect gender-critical belief, and which cases followed?

Forstater v CGD Europe arose from a workplace dispute during the United Kingdom’s 2018 consultation on reform of the Gender Recognition Act 2004. Maya Forstater, then a visiting fellow at CGD Europe, had expressed views on sex, gender identity, women’s rights and proposed self-identification reforms on social media. She contended that biological sex is real, important and immutable, and that it should not be conflated with gender identity.

NHS England, the royal colleges and institutional reversal

How did British medical institutions move from affirmation to caution, and which bodies still resist?

England’s institutional change did not begin with the Cass Review, but Cass gave it a formal evidential and administrative centre. For much of the previous decade, the NHS pathway for adolescents who met specialist criteria assumed that puberty suppression could precede masculinising or feminising hormones. NHS England’s 2016 policy provided for cross-sex hormones from “around” age 16 within the Tavistock’s Gender Identity Development Service (GIDS), while describing puberty blockers as part of the available treatment pathway after assessment and pubertal staging (NHS England, 2016). ([england

Puberty blockers in the UK: the evidence, the ban and the trial

Why did the UK stop routine prescription of puberty blockers, and what is the proposed clinical trial?

Puberty blockers are gonadotrophin-releasing hormone analogues, or GnRHa medicines. They suppress the hormonal signals that drive puberty. In paediatric medicine they have established licensed uses, including treatment for central precocious puberty. Their use for children and adolescents experiencing gender incongruence or gender dysphoria is different: it is off-label, meaning that the medicines have not been authorised by the regulator for that indication.

Scotland's Gender Recognition Reform Bill and the Section 35 order

What did the Scottish bill propose, why did the UK government block it, and what happened in court?

The Gender Recognition Reform (Scotland) Bill was presented as a reform of the Gender Recognition Act 2004 process in Scotland. A Gender Recognition Certificate, or GRC, is a legal document issued under the 2004 Act. Before the proposed Scottish changes, an applicant normally had to be at least 18, provide medical reports including a diagnosis of gender dysphoria, show that they had lived in the acquired gender for two years, and apply to a UK Gender Recognition Panel.