EHRC’s interim guidance on biological sex taken down following legal challenges

In April 2025, the Supreme Court confirmed in the case of For Women Scotland Ltd v The Scottish Ministers (“FWS”) that, for the purposes of the Equality Act 2010, the definition of “sex” is biological sex. This relies upon a binary definition of sex: for intersex people, their “biological sex” will be the sex that they were assigned at birth. The FWS decision was widely publicised, due to its far-reaching implications on the application of the Equality Act 2010. There remains a lot of uncertainty in this area, and much of this developing area of law remains untested. Organisations are best placed to be extremely cautious and take expert legal advice on policy and decisions which could be affected by this decision.

What did the Supreme Court decide?

Prior to FWS, it had been widely understood that the possession of a Gender Recognition Certificate could change a person’s sex for the purposes of the Equality Act 2010, and that a transgender person could be grouped with individuals with the same gender when applying the provisions of the Equality Act 2010. The FWS decision means that transgender women do not have the protected characteristic of being a woman, and transgender men do not have the protected characteristic of being a man. Transgender people are protected against discrimination in respect of their biological sex, and in respect of their protected characteristic of gender reassignment.

The implications of this are still not fully understood. The law in this area is nuanced and fact specific; there is not a one-size fits all answer. The court was clear that organisations still must have mind not to discriminate against transgender individuals; for example, a decision to make a service or provision single-sex could still be discriminatory against transgender individuals under the Equality Act. There are various conditions which must be met in order for a service to be provided on a single or separate sex basis, but there are also circumstances in which not providing a service on a single-sex basis could put an organisation at risk of claims.

The EHRC guidance 

On 25 April 2025, nine days after the Supreme Court decision, the EHRC released updated interim guidance, in respect of the changes arising from the FWS decision. The EHRC confirmed that the interim guidance is to be superseded by the updated Services Code, which is statutory guidance on the Equality Act 2010. The draft code was submitted to the Minister for Women and Equalities for approval on 4 September 2025 and is eagerly awaited by many organisations.

The Good Law Project (and other Claimants) have issued a legal challenge against the EHRC interim guidance, stating that it contains a series of legal errors, and has been published in breach of the EHRC’s statutory duties. The Claimants argue that the guidance either (i) is legally flawed and misrepresents the position under the Equality Act 2010, or, failing this, (ii) the Equality Act is incompatible with the Human Rights Act 1998. This challenge is due to be heard later this month. In October, the EHRC took down the interim guidance. 

The above further demonstrates the complexities and uncertainty in this area. Organisations are best placed not to rely on the interim guidance or other online resources for the time-being. The EHRC now advises as follows: “duty bearers should: … continue to take specialist legal advice, as before, on their obligations under any relevant legislation, including the Equality Act 2010 and Human Rights Act 1998”.