LONDON (AP) — The drama of Britain's exit from the European Union was being acted out this week on two of London's grandest stages: the Supreme Court and the House of Commons chamber. The plot is gripping, but the ending is still a mystery.
Inside the Supreme Court building, lawyers and judges on Thursday wrapped up four days of hearings about who has the power to trigger the EU exit — lawmakers or the government. In the nearby House of Commons, on the other side of Parliament Square, British legislators have been debating when that should happen and how it should unfold.
David Neuberger, president of the Supreme Court, said the judges would rule on the complex case "as quickly as possible." That's likely to be in January.
Almost six months after Britons voted in a referendum to leave the EU, some aspects of the way forward are clear, but many remain uncertain.
THERE'S A TIMETABLE BUT NOT A ROADMAP
Lawmakers have voted to back Prime Minister Theresa May's March 31 deadline to start the U.K's. formal exit from the EU, after the government agreed to publish details of its negotiating plan.
May's Conservative government has been reluctant to reveal much about its strategy or goals, saying that would weaken its hand in negotiations with the EU. But facing defeat on an opposition motion Wednesday calling for it to disclose more details, the government agreed to publish "strategic plans" — though it's not clear how detailed they will be.
In return, lawmakers voted by a large majority to state Parliament's support for triggering two years of EU exit talks by March 31.
Both pro- and anti-Brexit forces are claiming the result as a victory. Labour Brexit spokesman Keir Starmer said the opposition was bringing "clarity, scrutiny and accountability" to the divorce process. Anti-EU Conservative lawmaker Iain Duncan Smith said the Commons had given the government a "blank check" for Brexit.
At the Supreme Court, government lawyer James Eadie said the lawmakers' vote meant "the House of Commons has given specific approval to the government to give that (Article 50) notice." But he conceded the vote is not legally binding.
THE BALL IN THE JUDGES' COURT
The immediate future of the Brexit process rests in the hands of 11 Supreme Court justices.
They have been asked to rule on a major constitutional issue: Does the power to take Britain out of the EU rest with the executive — May's government — or with Parliament?
The government argues it can use powers known as royal prerogative to invoke Article 50 of the EU's key treaty, the formal trigger for exit talks from the 28-nation bloc. Prerogative powers have been used for centuries — originally by monarchs, now by politicians — to join or leave international treaties without a vote in Parliament.
Lawyers challenging the government say leaving the EU will change Britain's laws and remove citizens' rights, including free movement within the bloc — and that can't be done without legislation in Parliament.
David Pannick, lawyer for lead claimant Gina Miller, said British law contains "scores, hundreds of statutes which implement EU law," and these cannot be wiped away by "a minister acting without parliamentary authority."
The case is further complicated by Britain's regional structure. Scotland, Wales and Northern Ireland all have their own legislatures, and lawyers have argued to the court that they, too, should get a say.
Scotland's top law officer, James Wolffe, told the court Thursday that "fundamentally, this case is about who has the power to change the law of the land."
ENEMIES OF THE PEOPLE?
This case is considered so important that it is being heard by all 11 Supreme Court justices, the first time that has happened since the court was established in 2009.
Some supporters of Brexit think the judges are exceeding their authority by considering the case at all. The Daily Mail has branded the justices "enemies of the people."
Inside the court, the legal argument was restrained, elegant and intellectual, ranging from the Glorious Revolution of 1688 to the World War II traitor Lord Haw-Haw and a dispute over Newfoundland lobster fishing.
But outside — and online — the case has inflamed the debate over Brexit with venom and vitriol. Miller, one of the claimants in the case against the government, says she has received online abuse and death threats.
As he adjourned the court Thursday, Neuberger said "it bears repeating that we are not being asked to overturn the result of the EU referendum."
"The ultimate question in this case concerns the process by which that result can lawfully be brought into effect," he said.
UNCERTAIN NEW YEAR
If the government loses in court, it will have to introduce legislation to trigger Article 50 — and it won't have much time to get it through the House of Commons and the House of Lords if it wants to meet the March 31 deadline.
Most pro-EU British lawmakers have said they will not try to overturn the referendum result. But they could seek to amend the legislation in a bid to soften the divorce terms and avert a "hard Brexit" in which Britain crashes out of the EU's tariff-free single market in goods and services.
And the unelected Lords, where May's Conservatives do not have a majority, could try to delay the bill.
In one of the few statements all sides in court could agree on, Welsh government lawyer Richard Gordon said "the Brexit vote split the United Kingdom."
"It is almost the most divisive political event that has happened over the last several decades," he said.
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