Brexit Ruling at Supreme Court Could Test Unity of the U.K.

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Fresh from a bruising encounter at the hands of European Union judges, the British government faces yet another Brexit case on Thursday -- this time at the Supreme Court in London.

At issue is a question that goes to the heart of the United Kingdom’s constitutional setup: Can Scottish First Minister Nicola Sturgeon lawfully pass her own rival Brexit bill?

The bill was the Scottish parliament’s response to Prime Minister Theresa May’s nationwide withdrawal legislation which Sturgeon says would see hard-fought local powers transferred straight back to London if and when the U.K. leaves the European Union.

A ruling will come just hours after May faces a confidence vote from Conservative Party members of Parliament amid growing opposition to her Brexit deal.

How did we get this far?

In the 2016 referendum, Scotland voted emphatically to remain in the EU and the devolved government feels very strongly on the subject. The Scottish parliament passed its own Continuity Bill while resisting May’s main Brexit legislation. Sturgeon called the U.K.-wide measures a "naked power grab."

What is the legislation?

Passed in March, the Scottish legislation seeks to preserve devolved powers when EU law is converted into British law. It would also allow Scotland’s laws to keep pace with EU rules going forward.

And what is the Supreme Court ruling on?

The U.K. government has asked the panel of seven judges to decide if the Continuity Bill is constitutional. It says the Withdrawal Bill already covers the whole country and that devolved powers will then be passed back to Scotland. Local officials in the parliament also had their own doubts about the legality of the Scottish measures.

What happens if May wins?

It would allow May to impose British sovereignty. "The Brexit process has raised some concerns that the status of the Scottish parliament is being undermined," says Nicola McEwen, politics professor at the Centre on Constitutional Change at Edinburgh University. "If the court finds in favor of the U.K. Government, those concerns may be confirmed."

And what if the Scottish win?

The EU’s top court said on Monday that the U.K. could, if it chose to, revoke its intention to leave the bloc. May’s team of lawyers tried to kill the case -- brought by a group of Scottish lawmakers -- because they said the government had no intention of performing a U-turn.

By contrast, Thursday’s case can’t stop Brexit but if different parts of the country are able to retain EU law in different ways, it will introduce uncertainty for any business that operates across the U.K., said Akash Paun, senior fellow at the Institute for Government in London.

What’s the bigger picture?

For the U.K. to challenge the status of Holyrood, as the Edinburgh-based Scottish assembly is known, is politically sensitive. With Brexit, the Scottish government has been "cut out" of the decision-making, Paun said. It also risks playing into the hands of the nationalists who are trying to build a case for another independence referendum.

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