Britain’s Supreme Court to rule on legality of Parliament shutdown next week after unprecedented hearing

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Britain’s Brexit drama will take a new twist next week when the country’s Supreme Court rules on the legality of Prime Minister Boris Johnson’s decision to suspend Parliament for five weeks.

The high court ended an unprecedented three-day hearing Thursday during which Mr. Johnson was described as “the father of lies” and came under attack from former Conservative prime minister John Major. The President of the Supreme Court, Brenda Hale, said a ruling was expected early next week.

The decision could open the door to Parliament returning as early as next week, setting up another showdown over Brexit between Mr. Johnson and a rebel alliance of opposition and Conservative MPs. Mr. Johnson has been battling Parliament over his pledge to pull Britain out of the European Union on Oct. 31 – with or without a withdrawal agreement. A majority of parliamentarians have been trying to prevent a no-deal Brexit and recently passed a law that requires the Prime Minister to seek an extension if he hasn’t struck an agreement by Oct. 19. Mr. Johnson has indicated he will try to find a way around the law.

The Supreme Court has to decide whether Mr. Johnson’s decision to prorogue Parliament from Sept. 9 to Oct. 14 was entirely within his prerogative as Prime Minister or whether he was trying to stifle debate about Brexit.

The case comes after two lower courts recently came to contradictory conclusions. A court in London ruled that, according to constitutional convention, the Prime Minister’s decision was political and beyond judicial review. However, a panel of judges in Scotland found that the courts could examine the motivation for prorogation and ruled that Mr. Johnson misled the public and tried to thwart Parliament.

During the Supreme Court hearing, Aidan O’Neill, a lawyer representing more than 70 MPs, urged the justices to uphold the Scottish ruling.

“We’ve got here the mother of parliaments being shut down by the father of lies,” he told the court. “Rather than allowing lies to triumph, listen to the angels of your better nature and rule that this prorogation is unlawful and an abuse of power which has been entrusted to the government.”

Mr. Major joined the attack on his successor, arguing in a written filing that Mr. Johnson had not been truthful and that the court must intervene. The inescapable conclusion from Mr. Johnson’s actions, Mr. Major wrote, was that "the decision was in fact substantially motivated by a desire to obstruct parliament from interfering with the Prime Minister’s plans.”

His lawyer, Edward Garnier, added: “This isn’t a case where statements made, other than through the formal court process, can be taken to be the whole truth and nothing but the truth and at their face value.”

Mr. Major, who was in office from 1990 to 1997, has emerged as a formidable critic of Mr. Johnson’s Brexit strategy. He opposes a no-deal Brexit and has criticized Mr. Johnson’s approach as “bluster and threat.”

And he’s not the only former Conservative prime minister to take on Mr. Johnson. David Cameron, who resigned after the Brexit referendum in 2016, has also been scathing. In his recently released memoirs, Mr. Cameron accuses Mr. Johnson of lying during the referendum and caring only about his political future when he decided to co-chair the Vote Leave campaign.

Mr. Johnson has insisted that the prorogation had nothing to do with Brexit and that Parliament usually shuts down for a couple of weeks in the fall to accommodate annual political conventions. He added that as a new prime minister he also wanted to start a fresh session with a throne speech to outline his priorities. During the court hearing, a lawyer for the government, Richard Keen, said the decision to suspend Parliament was beyond the reach of the judges.

“This is forbidden territory" and takes the court “into an ill-defined minefield that the courts are not properly equipped to deal with," he said.

As the hearing wound down, the EU issued an ultimatum to Mr. Johnson. Finnish Prime Minister Antti Rinne said Mr. Johnson had less than two weeks to come forward with concrete proposals to break the logjam over Brexit.

"If no proposals are received by the end of September, then it’s over,” Mr. Rinne said late Wednesday after a meeting in Paris with French President Emmanuel Macron.

Mr. Rinne is key because Finland currently holds the presidency of the European Council, which represents EU leaders. The post rotates among EU members, and Finland’s term runs until the end of the year.

Mr. Johnson has said he wants to strike a deal, but he has demanded changes to the so-called Irish backstop, a provision designed to keep the Irish border open after Brexit. He has yet to provide any written proposals. On Thursday, his officials said some ideas had been exchanged with EU negotiators, adding that Britain would not be held to “an artificial deadline.”

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