Major set-back: UK High Court says Parliament must approve Brexit

Judgement that MPs rather than government must trigger article 50 is likely to slow pace of UK’s departure from EU.

Parliament alone has the power to trigger Brexit by notifying Brussels of the UK’s intention to leave the European Union, the High Court has ruled. The judgement, delivered by the Lord Chief Justice, Lord Thomas of Cwmgiedd, is likely to slow the pace of Britain’s departure from the EU and is a huge setback for Prime Minister Theresa May, who had insisted the government alone would decide when to trigger the process. 

The Lord Chief Justice said that “the most fundamental rule of the UK constitution is that parliament is sovereign”. A government spokesman said that Ministers will appeal to the Supreme Court against the decision. The hearing will take place early next month.

The Lord Chief Justice said: “The Court does not accept the argument put forward by the government. There is nothing in the 1972 European Communities Act to support it. In the judgement of the Court the argument is contrary both to the language used by Parliament in the 1972 Act, and to the fundamental principles of the sovereignty of Parliament and the absence of any entitlement on the part of the Crown to change domestic law by the exercise of its prerogative powers.”

Unless overturned on appeal at the Supreme Court, the ruling threatens to plunge the government’s plans for Brexit into disarray as the process will have to be subject to full parliamentary control. Government lawyers had argued that prerogative powers were a legitimate way to give effect “to the will of the people” who voted by a clear majority to leave the European Union in the June referendum. 

But the Lord Chief Justice declared: “The government does not have power under the Crown’s prerogative to give notice pursuant to Article 50 for the UK to withdraw from the European Union.” By handing responsibility for initiating Brexit over to MPs, the three senior judges – Lord Thomas; the Master of the Rolls, Sir Terence Etherton, and Lord Justice Sales – have ventured on to constitutionally untested ground.

The legal dispute focused on Article 50 of the treaty on European Union, which states that any member State may leave “in accordance with its own constitutional requirements” – an undefined term that has allowed both sides to pursue rival interpretations.

The decision may undermine Prime Minister Theresa May’s authority in conducting negotiations with other EU states in the run-up to the UK’s withdrawal. The Court took barely two and a half weeks to deliver its judgement. Lawyers for the government had argued that the Prime Minister has authority under the royal prerogative – its executive powers – to give formal notification. 

The challengers maintained that parliamentary approval and legislation was required for such a fundamental change that would deprive millions of UK citizens of their legal rights. If ministers alone triggered Brexit they would be undermining the sovereignty of Parliament, it was argued.

© The Guardian