The role of parliament during the Brexit process

Constitution Unit Director Meg Russell is one of the authors of a new UK in a Changing Europe report, The Brexit Files: From Referendum to Reset, which was published today. In this post, Meg examines the role of parliament in the withdrawal process, and argues that the sidelining of parliament that was seen throughout the Brexit process continued throughout the Johnson and Sunak premierships. She concludes that MPs must work to ensure that the current government’s commitment to greater parliamentary scrutiny is given full effect and parliament’s reputation with the public is rebuilt.

Brexit threw into doubt much that was familiar in British politics, wider society and public life, but among the most fundamental was the role of parliament. Westminster has long been an iconic symbol of democracy and parliament sits at the pinnacle of our legal system. But it became the site of some fierce battles over Brexit, and the process led to it being repeatedly questioned and maligned.

The referendum and its aftermath

In the UK, parliament is officially ‘sovereign’ – serving as the highest source of constitutional and legal authority. It arguably has that status precisely because it represents the people; but for some the Brexit referendum challenged that traditional authority. In 2015, the bill to facilitate the referendum was approved by the House of Commons by an overwhelming majority – the Scottish National Party (SNP) alone resisted the plan. But this did not signify parliamentary support for Brexit, which most MPs were known to oppose – it was simply a vote to allow the people to decide. The clear expectation of many was that the voters would choose to remain in the EU.

The result was therefore a challenge for parliament. Some opponents of Brexit hoped that MPs would overturn the result. The government, with a narrow Commons majority under Theresa May, feared parliamentary skulduggery. An immediate question was whether parliament needed to approve the triggering of the Article 50 process. The government wanted to proceed without parliamentary approval, using its ‘prerogative powers’ over foreign affairs. But a case challenging that wound up in the Supreme Court, which ruled in parliament’s favour. It was not MPs who had brought the case, and they might have preferred not to confront the issue. But forced to choose they, again overwhelmingly, approved the trigger – many with a very heavy heart. Theresa May accused those seeking to involve parliament of ‘trying to subvert’ democracy. Judges ruling in parliament’s favour were branded ‘enemies of the people’ by the Daily Mail. These early skirmishes demonstrated multiple tensions which became familiar – between the government, parliament, the courts and the people.

Parliament and the withdrawal process

The referendum offered no specific vision of Brexit. Many in parliament were therefore keen to scrutinise the process and hold the government to account for its approach – as is normal for major policies. But the government was frequently resistant, and Brexiteers suspicious.

The biggest tensions arose over the ‘meaningful vote’ – which parliament forced on the government against its wishes in 2018, during the passage of the EU (Withdrawal) Bill. This gave MPs an in-principle veto over any Brexit deal negotiated by the government. The move was proposed by those who favoured a ‘soft’ (or no) Brexit. But hardline Brexiteers soon realised that it facilitated blocking of any negotiated outcome, leaving their preferred ‘no deal’ Brexit as the default. Unholy alliances of hardliners and Brexit opponents repeatedly inflicted huge humiliating defeats on Theresa May as she brought back compromises from Brussels. Most in her own party who hadn’t originally supported Brexit were prepared to fall in behind her, while those who had campaigned most vigorously for it joined other parties in opposing her. Notable among them was Boris Johnson, who seized the opportunity to undermine May, ultimately replacing her when her inability to win support for a Brexit deal resulted in her being toppled by her party.

Throughout this period there was much procedural innovation, as parliamentarians sought to press alternative outcomes – including a ‘softer’ Brexit or a second referendum. These episodes raised fundamental questions, about the extent to which MPs or the government ought to control the Commons’ agenda, and about the role of the Commons Speaker. Both questions were fiercely fought. Amidst the disagreements, both May and the hardline Brexiteers (ironically including those using parliament to block her) indulged in increasingly anti-parliamentary rhetoric, which risked stoking public anger against this most central institution.

Attempts to shut down parliament

The day after Johnson took over, in July 2019, parliament adjourned for its summer recess. Before it reconvened, Johnson’s government announced that he had advised the Queen to grant a five-week ‘prorogation’ – which would shut parliament down completely. This would run close to the then deadline for the Article 50 negotiations, making a no deal Brexit more likely. The move resulted in a second Supreme Court case, which again found in favour of parliament, with the judges ruling Johnson’s lengthy proposed prorogation unlawful. By this point, public opinion was highly polarised, with Brexit supporters favouring the prorogation, and opponents favouring the court. The court’s judgment sought to articulate (in unusual detail) the central role of parliament, and parliamentary scrutiny, in the constitution. Nonetheless, its analysis was not accepted by all.

To sidestep the problems of the attempted prorogation, Johnson’s internal party critics joined forces with opposition parties to force an extension of the negotiation deadline and defer the risk of no deal Brexit. He retaliated with unique severity, immediately stripping his Conservative opponents of the whip. He subsequently succeeded in persuading MPs into an early election to break the deadlock, an election at which many of these key critics therefore couldn’t stand for the party. His landslide victory was won on a manifesto claiming that Britain had been ‘paralysed by a broken parliament’. Soon afterwards his Brexit deal was approved by MPs, and his future relationship treaty, negotiated a year later, was pushed through both chambers in a single day.

The legacy of Brexit

Brexit was immediately followed by Covid, which makes it hard to disentangle the effects. But both processes saw an increased sidelining of parliament – including through the heavy use of ‘delegated legislation’ to deliver huge policy changes quickly. The rhetoric directed at the institution did little to encourage public confidence, though during Johnson’s tenure, survey evidence suggested that the public favoured strengthening parliament against government, rather than the other way around. Nonetheless, declining standards of scrutiny lived on. Analysis shows that on some key measures, Rishi Sunak’s government treated parliament even worse than Johnson’s had. Labour entered power in 2024 on promises to improve scrutiny, and rebuild parliament’s reputation. But these are not easy goals, and not easy promises to keep in government. MPs have crucial roles, as do others, in holding the new government to its word.

This blog was originally published in UK in a Changing Europe’s report, The Brexit Files: From Referendum to Reset. Other chapters cover constitutional topics such as designing the referendum, Northern Ireland, the 2017 and 2019 general elections, the role of the courts, the impact on the Conservative and Labour parties, public opinion, the law, machinery of government, the civil service and devolution.

About the author

Meg Russell FBA is Professor of British and Comparative Politics at UCL and Director of the Constitution Unit.