British high court hears challenge to EU exit plan

LONDON — Britain’s top judges pledged Monday to consider with impartiality the contentious question of who has the power to trigger the United Kingdom’s exit from the European Union — the government of Prime Minister Theresa May or Parliament.

The court’s most senior justice, David Neuberger, opened a four-day hearing by condemning the “threats of serious violence and unpleasant abuse” directed at lead claimant Gina Miller and others arguing that Parliament should have a say.

Neuberger and 10 other justices at the country’s top court must decide whether May’s government can invoke Article 50 of the EU’s key treaty, the trigger for two years of divorce talks, without approval from lawmakers.