U.S. Supreme Court

Brexit dominates UK politics, from Supreme Court to Commons

The drama of Britain's exit from the European Union was being acted out this week on two of London's grandest stages: the Supreme Court and the House of Commons chamber. The plot is gripping, but the ending is still a mystery.

Inside the Supreme Court building, lawyers and judges on Thursday wrapped up four days of hearings about who has the power to trigger the EU exit — lawmakers or the government. In the nearby House of Commons, on the other side of Parliament Square, British legislators have been debating when that should happen and how it should unfold.

David Neuberger, president of the Supreme Court, said the judges would rule on the complex case "as quickly...