Top UK judges grill government lawyer on Brexit plans

British government legal council James Eadie speaks at the Supreme Court in this image taken from video in London, Monday Dec. 5, 2016 . The Supreme Court began hearing a landmark case Monday about who has the power to trigger Britain's exit from the European Union the government or Parliament. (The Supreme Court via AP) (The Associated Press)

This is a general view of the Supreme Court, with the judges at right and legal councils at left, in this image taken from video in London, Monday Dec. 5, 2016 . The Supreme Court began hearing a landmark case Monday about who has the power to trigger Britain's exit from the European Union the government or Parliament. (The Supreme Court via AP) (The Associated Press)

Protestors in costume demonstrate outside the Supreme Court in London, Monday, Dec. 5, 2016. May's government will ask Supreme Court justices to overturn a ruling that Parliament must hold a vote before Britain's exit negotiations can begin _ a case that has raised a constitutional quandary and inflamed the country's heated debate about Brexit. (AP Photo/Frank Augstein) (The Associated Press)

British Supreme Court judges are grilling a government lawyer for a second day over plans to trigger the U.K.'s divorce from the European Union without a vote in Parliament.

Lawyer James Eadie is arguing that the government has the authority under ancient powers known as royal prerogative to enact voters' decision to leave the EU.

High Court judges ruled last month that a vote by lawmakers was needed first. The government is challenging that decision at the country's top court.

Eadie argues that Parliament has already had its say, by passing the law that made June's EU membership referendum possible.

On the second day of the hearing Tuesday, judges pressed Eadie for details and at one point accused him of giving contradictory answers.

The hearing is due to end Thursday.