The Scottish Government should have expected that London would restrict its authority over devolved powers returning from Brussels after Brexit, the UK’s top law officers have told the Supreme Court.
On the second day of a hearing in the UK’s legal challenge against Scottish Brexit legislation, Advocate General for Scotland Lord Keen told Supreme Court justices it was “unjustified” for devolved governments to expert all devolved powers to be handed over after leaving the EU, because devolution “did not anticipate Brexit”.
A ruling from the panel of seven justices is not expected before October. The Supreme Court can either rule that Holyrood’s Continuity Bill is out of its competence, or give the green light for it to receive Royal Assent. Justices can also send portions of the bill back to Holyrood to be revised.
The majority of Wednesday’s hearing was dedicated to the Scottish Government’s case, which was laid out by Lord Advocate James Wolffe QC, who said the Holyrood legislation was “perfectly practical”.
READ MORE: Supreme Court Brexit challenge: ‘UK Parliament is sovereign, not Holyrood’
Mr Wolffe rejected the UK’s argument that the Scottish Parliament was seeking to cut across Westminster’s authority in international negotiations, insisting that EU law was “not a reserved matter”.
The Lord Advocate said the Holyrood bill “has effect only in the domestic legal order… it cannot affect the UK’s negotiations with the UK”.
He was backed by the QC for the Welsh Government, which intervened to support the Scottish Government’s argument.
Michael Fordham said the UK’s position that devolved administrations could not legislate in devolved areas currently managed by the EU because they touch on international treaty negotiations was an “extravagant claim which has very alarming logical implications” Mr Fordham said this would limit the powers of devolved parliaments even after the UK leaves the EU, and European law is transferred into British statute.
Northern Irish Attorney General John Larkin also argued that “the [Scottish] bill and all of its provisions are within the legislative competence of the Scottish Parliament”.
Delivering a response concluding the hearing on Wednesday, Lord Keen argued that “is was not open to the Scottish Government and the Scottish Parliament to assume that no new legislative constraints” would be introduced as a result of Brexit.
He said it was “a matter for the UK Parliament to determine where areas of current EU competence may appropriately lie”.
The Advocate General also insisted that “withdrawal from the EU is unquestionably a matter of international relations” because the post-Brexit statute book will be “inextricably bound up with the issue of withdrawal itself”.
READ MORE: Brexit: Why are the UK and Scottish Governments in a Supreme Court battle?
In oral arguments on Tuesday, Lord Keen had claimed the Continuity Bill was “fundamentally inconsistent” with the aims of the UK Government’s EU Withdrawal Bill, and that confusion over which parliament had jurisdiction over which European regulations would undermine Brexit.
Scottish ministers pushed ahead with the Continuity Bill after accusing Westminster of mounting a “power grab” on two dozen responsibilities in devolved areas such as agriculture and the environment, currently held by Brussels.
The legislation was supported by 95 MSPs from all parties except the Conservatives, despite a ruling from the Holyrood Presiding Officer it was not within the competences of the Scottish Parliament.
The case was heard by Lord Reed, Lord Sumption, Lord Carnwarth, Lord Hodge, Lord Kerr, Lord Lloyd-Jones, and Lady Hale, who closed the hearing by saying the justices would “apply the wet towels” to consider their judgement.