Lawyers invoke Claim of Right in battle to include Parliament in triggering of Article 50

Aidan O’Neill QC (pictured), representing the Independent Workers Union of GB, said that the Supreme Court must take account of Scotland’s constitutional law and hence the act, which codified the tradition that a monarch was answerable to the law and people.

He added that it must also take EU migrants’ rights and those of trade union members into account.

Jeremy Wright QC and others on the government’s legal team have released a skeleton argument which states: “Before the it was common ground between the parties that an article 50 notification is irrevocable and cannot be given conditionally … Court is invited to do the same.”

Lord Advocate James Wolffe QC (pictured right) said in a submission to the court that the claim of right made “a unilateral act of the Crown” unlawful.

Mr O’Neill’s submission states: “The contemporary significance and resonance of this Scottish tradition is clear in the present case. In effect, the Scottish constitutional tradition is not that the crown has plenipotentiary imperial prerogative ‘Henry VIII’ powers unless and until these are expressly limited by Parliament.

“Rather the Scottish constitutional tradition is that the Crown, the government, only has such powers as are expressly granted to it by the people gathered together in a representative assembly.”

He adds that the Sewel convention has legal force as a result of recent legislation, a de facto veto, contrary to Mr Wolffe, who acknowledges it only as a convention.