Key Points

In a unanimous ruling, the court clarified that the legal definition of "woman" in the context of the Equality Act (EA) 2010 is based on biological sex rather than gender identity.

A group of campaigners in Scotland brought the challenge in 2018, arguing that those rights should only safeguard those assigned as women at birth. But the Scottish government said that a trans woman with a GRC is legally a woman and should therefore be afforded the same legal protections, CNN reported.

In its judgment, the court said, "The Supreme Court unanimously allows the appeal. It holds that the terms 'man,' 'woman,' and 'sex' in the EA 2010 refer to biological sex. Lord Hodge, Lady Rose and Lady Simler give a joint judgment, with which the other Justices agree.

It added, "The definition of sex in the EA 2010 makes clear that the concept of sex is binary, a person is either a woman or a man. Persons who share that protected characteristic for the purposes of the group-based rights and protections are persons of the same sex and provisions that refer to protection for women necessarily exclude men. Although the word "biological" does not appear in this definition, the ordinary meaning of those plain and unambiguous words corresponds with the biological characteristics that make an individual a man or a woman. These are assumed to be self-explanatory and to require no further explanation. Men and women are on the face of the definition only differentiated as a grouping by the biology they share with their group."

The court further clarified that transgender individuals are still protected under the Equality Act 2010 through its provisions on indirect discrimination, regardless of whether they possess a Gender Recognition Certificate (GRC).

"Consequently, transgender people (irrespective of whether they have a GRC) are protected by the indirect discrimination provisions of the EA 2010 without the need for a certificated sex reading of the EA 2010, both in respect of any particular disadvantage suffered by them as a group sharing the characteristic of gender reassignment and, where members of the sex with which they identify are put at a particular disadvantage, insofar as they are also put at that disadvantage. Again, this does not entail any practical disadvantage or involve any discordance between the claim and the individual's position in society. On the contrary, the claim will be founded on the facts of a particular shared disadvantage. Transgender people are also protected from indirect discrimination where they are put at a particular disadvantage which they share with members of their biological sex," the ruling said.

- ANI