The U.K. Supreme Court's decision adds to the mounting rollback of protections for trans people across the globe.

The Supreme Court of the United Kingdom ruled Wednesday that trans women are not legally women under the British Equality Act.

Trans women are not legally women under the Equality Act, the Supreme Court has ruled in a landmark judgment. Campaign group For Women Scotland (FWS) brought a series of challenges – including to the UK’s highest court – over the definition of “ woman ” in Scottish legislation mandating 50 per cent female representation on public boards.