Lawyers for the Scottish and Welsh governments have been allowed to take part in the supreme court case over Theresa May’s decision to bar MPs from voting on Brexit.
In an unprecedented hearing, all 11 supreme court judges will convene in early December to rule on whether the Commons must be allowed to vote on triggering the article 50 process, against the UK government’s wishes.
The supreme court confirmed on Friday that the chief law officers for the Scottish and Welsh governments would be allowed to intervene, broadening the case into a legal battle over the role and status of three parliaments in the process.
Meanwhile in Belfast, a campaigner for victims of paramilitary violence has won the right to a hearing in the supreme court aimed at blocking Northern Ireland from leaving the EU. The high court ruled that Raymond McCord’s legal challenge against Brexit could be heard in London.
This month three high court judges in London ruled that the prime minister did not have the power to use the royal prerogative to invoke article 50 without parliamentary approval, a ruling now being challenged by May.
The UK government has rejected Scottish claims that Holyrood should have a direct say in triggering article 50. It argues that foreign affairs and legal treaties are matters entirely reserved for the UK government.
A UK government spokesman said it was up to the court who was allowed to take part. “The UK government’s position remains the same, and we will be taking strong legal arguments to court next month,” he said.
The supreme court’s statement on Friday suggested the Scottish government would play a relatively limited role in the hearings, and would be asked to focus on areas of Scottish law that were relevant and new to the case.
James Wolffe, Scotland’s lord advocate, has been asked “to address in their skeleton arguments the relevance of points of Scots law, so far as they do not also form part of the law of England and Wales, to the determination of the present proceedings.”
A court spokesman said there had been no Scottish court proceedings on Brexit in which these arguments had been aired. The issues under English law had already been debated in the earlier judicial review.
The court also said the Independent Workers Union of Great Britain, a new trade union formed to represent contract staff and “gig economy” workers such as couriers, would also be allowed to intervene on the Scottish law element. A fourth applicant, named as the “Expat Interveners, George Birnie and others”, was also allowed to take part.
Nicola Sturgeon, Scotland’s first minister, said this month that invoking article 50 raised substantial questions about the rights of the Scottish parliament since it had clear legally defined powers and duties in areas directly affected by the EU.
“The Scottish government is clear that triggering article 50 will directly affect devolved interests and rights in Scotland,” she said. “And triggering article 50 will inevitably deprive Scottish people and Scottish businesses of rights and freedoms which they currently enjoy.
“It simply cannot be right that those rights can be removed by the UK government on the say-so of a prime minister without parliamentary debate, scrutiny or consent.”
The lord advocate’s submission to the supreme court said leaving the EU would lead to Scottish residents and businesses including EU citizens now resident in Scotland “losing rights and freedoms which they currently enjoy.”
It would also result in a significant change to the Scottish parliament’s powers and functions, and potentially sidestep the convention where Holyrood’s consent to such changes should be sought.
Scottish and Welsh government lawyers sat in as observers on the first judicial review that led to next month’s supreme court hearing.
Mike Russell, the Scottish government’s Brexit minister, urged May to drop the supreme court appeal and allow Westminster to vote on article 50.
“Parliament has the right to determine the triggering of article 50,” Russell said. “We recognise the decision of people in England and Wales to support Brexit, but the views of people in Scotland cannot simply be brushed aside.”
The Welsh government was the first to call for the right to intervene, on 4 November, but it, unlike the Scottish government, has accepted the decision to leave the EU, after Wales voted narrowly in favour of Brexit.
Mick Antoniw, counsel general for Wales, said the article 50 hearing “raise[s] issues of profound importance” for the devolved nations. The Welsh government is also anxious to ensure its voice is not drowned out in the coming months.
“This case is not about whether the UK leaves the EU or not,” Antoniw said on Friday. “The people have voted for the UK to leave the EU, and the UK will leave. The sole legal question at issue is whether the UK government can, as a matter of constitutional law, use the prerogative powers to give notice of withdrawal from the European Union.”