While Britain's highest court said there was no clear winner in its ruling, trans groups said the decision would undermine their rights.

The force has become one of the first to announce a change of policy in light of the divisive court ruling. It means that trans women in custody will be searched by male officers, while officers who are trans women will no longer be able to search female detainees.

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