A prominent law firm is taking pre-emptive legal action against the government, following the EU referendum result, to try to ensure article 50 is not triggered without an act of parliament.

Acting on behalf of an anonymous group of clients, solicitors at Mishcon de Reya have been in contact with government lawyers to seek assurances over the process, and plan to pursue it through the courts if they are not satisfied. The law firm has retained the services of senior constitutional barristers, including Lord Pannick QC and Rhodri Thompson QC.



Their initiative relies upon the ambiguous wording of article 50 of the Treaty on European Union, which sets out how states could leave the EU. The first clause declares: “Any member state may decide to withdraw from the Union in accordance with its own constitutional requirements.”

One of the grounds of a likely challenge to the referendum is that it is merely advisory and the royal prerogative cannot be used to undermine parliamentary statute.



According to Mishcon de Reya, the decision to trigger article 50 rests with the representatives of the people under the UK constitution. The firm has been in correspondence with the government since 27 June “to seek assurances that the government will uphold the UK constitution and protect the sovereignty of parliament in invoking article 50”.



Kasra Nouroozi, a partner at Mishcon de Reya, said: “We must ensure that the government follows the correct process to have legal certainty and protect the UK constitution and the sovereignty of parliament in these unprecedented circumstances. The result of the referendum is not in doubt, but we need a process that follows UK law to enact it. The outcome of the referendum itself is not legally binding and for the current or future prime minister to invoke article 50 without the approval of parliament is unlawful.

“We must make sure this is done properly for the benefit of all UK citizens. Article 50 simply cannot be invoked without a full debate and vote in parliament. Everyone in Britain needs the government to apply the correct constitutional process and allow parliament to fulfil its democratic duty, which is to take into account the results of the referendum along with other factors and make the ultimate decision.”

The UK does not have a formal written constitution, so some lawyers have been dismissive of the legality of legal intervention, while others have been pressing for clearer guidance on the constitutional procedure.

Another legal initiative began last week to seek an opinion on whether the advisory status of the referendum means that it should be the prime minister or parliament that ultimately pulls the trigger on article 50.

A tax barrister, Jolyon Maugham QC, has launched a crowdfunding campaign on CrowdJustice to pay for advice from constitutional law experts.

“This is an incredibly important moment in our nation’s history,” Maugham said. “Everyone – those who voted both leave and remain – is entitled to be sure of the constitutional basis for removing the UK from the EU.”