The U.K. must hold a vote in Parliament before starting the two-year countdown to Brexit, a panel of London judges decided, likely setting up a constitutional confrontation at the country’s Supreme Court next month.
“If notice is given under Article 50, it will inevitably have the effect of changing domestic law,” Judge John Thomas said Thursday, delivering a decision that is a setback for Prime Minister Theresa May’s plan to unilaterally start the process by the end of March by invoking Article 50 of the Lisbon Treaty.
The decision in London comes less than a week after a Northern Irish judge rejected a pair of challenges to the Brexit process, and the Supreme Court has already set aside time for an appeal hearing Dec. 5 to 8, a government lawyer said. Investors have looked to the lawsuits to delay Brexit amid concerns that the prime minister is prioritizing immigration controls over safeguards for trade and banking. The June 23 referendum has caused the pound to lose 17 percent of its value — more than any other major currency — before the ruling over fears that whatever deal emerges from negotiations between May and the EU will leave the country worse off.
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“It might mean that the Prime Minister has to show her hand a little more,” said Stephanie Flanders of JPMorgan Asset Management in an interview on Bloomberg Television. It’s likely to mean “a bit more transparency about the deal and a bit more of a debate domestically. I would not assume that the pound stays up from here or that we’re not leaving the EU.”
Liam Fox, the trade secretary, said the government would examine the ruling carefully.
The London legal challenge, brought by Gina Miller, who runs an investment startup, and Deir Dos Santos, a hairdresser, sought a court ruling that it would be illegal for the government to invoke Article 50 without first consulting Parliament.
Last month in Belfast, Justice Paul Maguire rejected a pair of challenges to the Brexit process, ruling that it was beyond the power of the Belfast court to interfere in how the government triggers Article 50. He dismissed claims related to lawmakers’ votes and the Good Friday Peace accord in Ireland.
During the London hearings, Attorney General Jeremy Wright said that the challenge at its basic level was an attempt to interfere with democracy. Lawyers representing the claimants said that May’s bid to trigger Brexit on her own would amount to an unconstitutional power grab that tramples upon centuries of legal precedent.
Triggering Article 50 is “irrevocable,” Wright said during the case.