Lawyers argue Theresa May can start Brexit process

British government lawyers faced tough questioning at the supreme court on Monday as they argued that prime minister Theresa May can start the process of leaving the EU without seeking parliamentary approval.

Attorney general Jeremy Wright told the 11 judges that the high court was wrong to rule that MPs must have their say before the government triggers article 50 of the Lisbon Treaty, which starts formal Brexit negotiations.

He said that successive parliaments had agreed that governments could use prerogative power to negotiate international treaties and agreements, including those involving the EU.

“We say the use of the prerogative in these circumstances was not only lawful but supported by the constitutional settlement,” he said.

James Eadie QC, who was also representing the government, said that the power to make war and peace have long been part of the government’s executive powers.

“It’s no small thing to alter the constitutional balance by limiting long-standing powers,” he said.

Mr Eadie faced detailed probing from the judges, however, when he asserted that the government’s authority to renegotiate the terms of Britain’s relationship with the EU over the past four decades automatically extended to leaving it altogether.

Threats

The government appealed to the supreme court after Gina Miller, a businesswoman, and Deir Dos Santos, a Spanish-born hairdresser, successfully argued in the high court that MPs must approve the triggering of article 50 because leaving the EU would remove rights conferred on British citizens when parliament voted to join the common market in 1972.

At the start of Monday's proceedings, supreme court president Lord Neuberger condemned threats made to Ms Miller and Mr Dos Santos and banned the publication of their home addresses.

“Threatening and abusing people because they are exercising their fundamental right to go to court undermines the rule of law. Anyone who communicates such threats or abuse should be aware that there are legal powers designed to ensure that access to the courts is available to everyone,” he said.

The court will also consider interventions from the Scottish and Welsh governments and two cases from Northern Ireland, one brought by a group of politicians and civil society groups, and the other by Raymond McCord, a campaigner on behalf of victims of violence.

The politicians, who include SDLP leader Colum Eastwood and the Alliance Party’s David Ford, want the court to determine if any provisions of the 1998 Northern Ireland Act, the Good Friday Agreement (GFA) and the British-Irish Agreement, mean that an Act of parliament is needed before triggering article 50.

The court will also consider if Stormont must have a role in approving the start of Brexit negotiations, and whether triggering article 50 without parliamentary approval could breach equality legislation introduced after the Good Friday Agreement.

Consent

Mr McCord, whose son was murdered by loyalist paramilitaries in 1997, posed the same four questions, along with a fifth asking if the consent of the Northern Ireland public is required before starting Brexit negotiations.

A majority of voters in Northern Ireland voted to remain in the EU in June’s referendum and Mr McCord argues that leaving the EU will change the constitutional status of Northern Ireland without the consent of its people.

“The GFA expressly provides that ‘it would be wrong to change the status of Northern Ireland without the consent of its people’ . . . The transfer of law-making power from EU institutions to Westminster is unacceptable to them. The removal of EU citizenship rights which serve to dilute the significance of Irish or British citizenship is unacceptable,” Mr McCord’s lawyers said in a written submission to the court.

Representatives from the Irish embassy in London were in court on Monday to observe proceedings, which will continue until Thursday, with a decision expected next month.