A legal challenge against the Scottish Parliament’s Brexit bill has begun at the Supreme Court in London.
MSPs passed the bill, an alternative to Westminster’s EU Withdrawal Bill, in March amid a long-running row over post-Brexit powers and devolution.
Holyrood’s presiding officer had raised questions over whether the legislation was within the parliament’s remit, and UK law officers challenged it in court.
However the Scottish government insists the bill should be allowed to stand.
The Welsh and Northern Irish assemblies will also be represented in the two-day hearing, having made submissions backing the Scottish government’s stance.
A judgement is not expected until later in the year.
- Follow the hearing live on the Supreme Court website and via BBC reporters Philip Sim and Nick Eardley on Twitter
- Supreme Court showdown – what’s it all about?
- What is the continuity bill?
The UK Withdrawal from the European Union (Legal Continuity) (Scotland) Bill – known as the “continuity bill” – was passed under emergency procedures with only the Conservatives and a single Lib Dem MSP voting against it.
But before it could become law, it was referred to the Supreme Court by UK law officers to settle whether it lies within Holyrood’s competence.
Presiding Officer Ken Macintosh penned an official memo saying the bill was “not within the legislative competence of the parliament”, as it would see MSPs “make provision now for the exercise of powers which is it is possible they will acquire in future”.
This was denied by Lord Advocate James Wolffe, the Scottish government’s top legal adviser, who insisted the legislation was “carefully framed” not to cut across EU laws – and said it was designed on the Withdrawal Bill in that regard.
The UK government’s senior law officers said they wanted the Supreme Court to look at the bill to ensure there was “legal certainty” about whether it is valid.
Arguments are being heard at the Supreme Court by Lady Hale, Lord Reed, Lord Sumption, Lord Carnwarth, Lord Hodge, Lord Kerr and Lord Lloyd-Jones.
They will hear from legal representatives of the Scottish and UK governments, as well as the counsel general for Wales and the Northern Irish attorney general, who have made submissions as interested parties.
Both have backed the Scottish government’s view that Holyrood should be allowed to legislate on Brexit.
The Welsh government originally had a Brexit bill of its own, which also faced a court challenge, but the legislation was withdrawn after Welsh ministers came to an agreement with UK counterparts over the Withdrawal Bill.
The three options open to the judges are to give the bill the green light, to reject it entirely, or to allow some sections to stand while rejecting others.
Should any part of the bill be struck down, it would go back to Holyrood for MSPs to consider making changes.
The Scottish and UK governments have been unable to agree on how powers currently exercised from Brussels are to be used after the UK leaves the EU in March 2019.
Both sides agree that certain powers should be used to set up UK-wide frameworks of common rules and regulations, in fields like food standards and labelling. But ministers cannot agree on who should have the final say over how this should be done.
Scottish ministers say giving Westminster the final say is a “power grab” from Holyrood, while Whitehall ministers say they cannot give MSPs a “veto” over UK-wide plans.
With the dispute deadlocked, MSPs refused to give their consent to the EU Withdrawal Bill, giving fresh importance to the issue of the continuity bill and whether it will be allowed to stand.
The Scottish government has also indicated that it will not put any of the UK government’s further Brexit legislation forward for consent votes at Holyrood until the row has been resolved.
Speaking ahead of the court hearing, Scottish Secretary David Mundell said: “Given the view of the Scottish Parliament’s presiding officer that the Continuity Bill was not within the legal scope of the parliament, we believe it is important to ask the Supreme Court to provide absolute clarity.
“The legislation which set up the Scottish Parliament anticipated such a situation, and we are simply following the legal process set out in the 1998 Scotland Act.”
The Scottish government believes the UK government should not be attempting to settle a political dispute.
Ian Blackford, the SNP’s Westminster leader, told BBC Good Morning Scotland the Scottish government’s position has cross-party support at Holyrood.
He said: “It’s not about the SNP. It’s with the support of the Labour Party, the Liberal Democrats and the Greens.
“It’s to make sure that we support the powers that should be within the Scottish parliament. It’s about the devolution settlement from 1998.”
Submissions from UK law officers are expected to take up most of the first day of the hearing, while the Lord Advocate will respond on Wednesday.
Supreme Court case over Scottish Brexit bill begins}