The woman who would bring down Brexit: Smiling Remain campaigner Gina Miller arrives at the Supreme Court as judges prepare to announce whether Theresa May needs MPs' approval to trigger EU departure

The 11 top judges are due to decide whether the Prime Minister can use executive powers to begin the formal process of leaving the EU - or if Theresa May must pass legislation. The government is widely expected to suffer another humiliating defeat in the wake of an earlier decision by the High Court. But Downing Street has already insisted the result will not change Mrs May's pledge to invoke the Article 50 process by the end of March.