Cabinet ministers have privately conceded that they are very likely to lose a landmark legal case on Brexit in the supreme court and have drawn up at least two versions of a bill that could be tabled after the ruling.
Sources have told the Guardian that senior government figures are convinced seven of the 11 judges will uphold the high court’s demand that Theresa May secure the consent of MPs and peers before triggering article 50.
It is understood that more than one possible bill has been prepared so that the ministers are ready to respond to any detailed guidance from the judges into what the legislation should look like.
It is not yet clear when the decision is likely, but the Guardian has been told that the government has asked the supreme court for early sight of the judgment, to allow “contingency planning”.
However, a spokesperson for the supreme court made clear on Wednesday that would not happen, saying: “It’s just too sensitive”.
Ministers hope the court will allow May to put together a short, three-line bill, or even just a motion, which is narrowly focused on article 50 itself and difficult for parliamentarians to amend.
However, Lady Hale – deputy president of the court – gave a lecture in November suggesting it was possible for the judges to go much further and demand a “comprehensive replacement” of the 1972 European Communities Act.
Dominic Raab, a Conservative MP and former minister who campaigned for Brexit, told the Guardian he and colleagues were not too worried about the case. “I hope we get some common sense from the supreme court, but I don’t expect the ruling to hold up triggering article 50, and the vast majority of people whichever way they voted now want us to get on and deliver Brexit,” he said.
However, some remain-supporting MPs and peers are hoping there will be an opportunity to amend legislation, for example to demand that the prime minister pursue the closest possible economic relationship with the EU.
The Liberal Democrats plan to lay down amendments demanding a Brexit deal be put to the public in a second referendum and that 16- and 17-year-olds get a vote.
Some pro-Brexit MPs have been urging the prime minister to adopt a “keep it simple strategy” – a phrase borrowed from management theory – ensuring any bill is as brief as possible, to minimise the risk it could be derailed.
Mark Harper, the former Tory chief whip who backed remain in the referendum, said he believed the supreme court would only be able to demand that the government either produce a motion or a bill, but not demand any level of detail beyond that. He suggested May’s government would probably try to publish “something very tight that gives authority to ministers to trigger article 50 before the end of March”.
Harper said that while it was not possible to avoid any amendments at all, a short and focused bill would make it difficult for MPs to cause trouble for May by constraining her room for manoeuvre during Brexit negotiations. He said that if he was still chief whip he would not be complacent about the process, but was “cautiously optimistic” that the legislation would be passed.
Any attempt by the government or the claimants to obtain advance notice of the supreme court decision has been stymied. In most cases it is normal practice for the lawyers involved to be sent the judgment on an embargoed basis beforehand.
In cases as sensitive as the article 50 appeal, the judgment is kept secret until the last moment to ensure that it does not leak out. A supreme court spokesperson said: “In view of the potential sensitivity of the case, there will be no copies of drafts available to anybody before the day of hand-down”.
Ministers are planning to move quickly after a judgment to avoid the days of speculation and anger that followed the high court ruling, which took the government by surprise. The first step is likely to be a statement to the House of Commons by the Brexit secretary, David Davis.
He is proving popular among MPs since taking up his role, with friends in the Conservative party planning a drinks reception this month to belatedly welcome him back to the frontbench. His ally Andrew Mitchell has joked that it is time for a celebration now it is clear that Davis, who stepped down as an MP in 2008, is not going to resign from this role.
One rumour circulating in Westminster is that the government plans to publish a press release claiming a win of sorts if four judges rule in favour of the government, while seven are against. That is the outcome that ministers believe is most likely.
And while they think they are likely to lose the case being brought by Gina Miller, which would require them to publish an act of parliament, they are more confident about other aspects. In particular, they do not think it is likely that the judges will order May to seek agreement from the Scottish and Welsh devolved administrations before starting the Brexit process.
The prime minister will give a speech setting out her approach later this month, and she will later publish a plan for Brexit after signing up to a motion put forward by the Labour party.
Moderate Conservative MPs had urged the government to table a formal white paper, setting out its priorities as it negotiates Brexit, including the answer to key questions such as whether May hopes to keep Britain in the single market or the customs union.
But they now expect May to publish a less definitive “menu of options” amid fears that a detailed white paper could constrain her room for manoeuvre in the coming months. “The government is still very concerned that if it puts forward a white paper, it will be subject to amendment,” said one backbencher.
Separately, the Scottish National party (SNP) is seeking to use the political crisis in Northern Ireland to ramp up the pressure on the government over its decision to table article 50 by the end of March. Northern Ireland, like Scotland, voted to remain in the EU, and the government has promised to take formal account of opinion in other parts of the UK through regular meetings of a joint ministerial committee as it enters talks.
Deirdre Brock, the SNP’s spokeswoman on Northern Ireland, challenged James Brokenshire on Monday. She asked the secretary of state for Northern Ireland: “Now that there is no effective administration at Stormont who can speak up for Northern Ireland in the joint ministerial committee, and remembering that Northern Ireland voted to remain, can he tell us what he is doing to ensure that the interests of the people of Northern Ireland are being looked after when Brexit negotiations are considered?”
