British Prime Minister Theresa May reacts after tellers announced the results of the vote Brexit deal in parliament in London, Britain, on March 12 2019. Picture: REUTERS
British Prime Minister Theresa May reacts after tellers announced the results of the vote Brexit deal in parliament in London, Britain, on March 12 2019. Picture: REUTERS

The UK parliament will try to take control of Brexit this week from a severely embattled prime minister. What will follow is anyone’s guess, but it is likely to include voting on the largest range of options for leaving the EU that MPs have formally considered.

One of those options is cancelling Brexit altogether.

The idea would almost certainly be rejected by parliament. But just debating the possibility of reversing course would itself be hugely important in shaping what follows.

Brexit can be cancelled if the UK revokes its 2017 decision to trigger Article 50 of the EU treaty, which gave notice of the intention to exit. That would have to be done before exit day itself, now extended to April 12 by the EU.

Until now, few legislators seriously entertained the idea. For one thing, revocation would raise deep questions of democratic legitimacy. How could Parliament decide to reverse the result of the nationwide popular referendum of 2016?

Moreover, the politics of revocation make it all but impossible to carry out. Both major political parties made commitments to honor the referendum result. While Labour MPs may be sympathetic to the idea, about two-thirds of them represent leave-voting constituencies and would have a hard time explaining it to their voters.

Labour leader Jeremy Corbyn has viewed leaving the EU as necessary for adopting some of the socialist policies that he would want a Labour government to pursue, and which would run afoul of EU rules. Brexit enthusiasm among Conservative Party stalwarts and the core party membership poses an even higher barrier for any Conservative MP considering revocation.

Even so, revocation is having a moment now. A petition to nullify Brexit achieved more than five-million signatures in a few days. That far exceeds the 100,000-signature threshold to trigger parliamentary debate. Organisers of a massive London protest that took place on Saturday say that the numbers marching in favor of a second referendum or cancelling Brexit altogether reached over a million (even if Brexiters dispute the number, they cannot argue with the aerial footage).

Another thing giving force to the Revoke argument are reports that Prime Minister Theresa May will side with hardline Brexiters in favour of an economically perilous no-deal departure if legislators do not approve her exit plan after twice rejecting it, rather than seek a long extension.

It may seem difficult to imagine a UK leader, let alone a Conservative one, backing such a drastic and reckless move. A no-deal exit would be quick and painful. It has been debated, discredited and rejected by Parliament already. But May’s priorities have always been to “deliver Brexit” and put Britain back in control of its borders by liberating it from the EU’s free-movement-of-labour rule, something leaving without a deal would do.

Finally, only two of the options parliament may consider — No Deal and Revoke — can be accomplished in the short period of time before the May 23 elections for the European Parliament. Many MPs on all sides of the debate are keen to avoid having the UK participate in those elections.

Most lawyers argue that the prime minister lacks the power to nullify the Article 50 action without legislative action by parliament (rather than a simple vote in favour). That case is made in a paper for the UK Constitutional Law Association by Gavin Phillipson and Alison Young.

Another authority on UK and EU law, Jolyon Maugham, has argued that the prime minister does have the discretion to reverse the Article 50 action. His is a minority view, but he’s also pointed out that as a practical matter, a judge would be unlikely to force the UK to leave the EU if parliament expressed a wish to the contrary.

Whether or not the issue ever comes before a judge or the British public, the debate over revocation has revealed significant changes in the political landscape as former pro-Brexit luminaries start to reconsider.

Oliver Norgrove, once an enthusiastic staffer in the campaign for leaving the EU, tweeted earlier in March: “I’m now at the stage where I think if we end up not leaving, it’ll be a blessing. Let’s face it, my side just doesn’t deserve it.”

The Brexit process, he said, had been “self-deception on an almighty scale.” He was welcomed by Remainers as a prodigal son.

The needle began to move for Norgrove when he realised that Brexiters had missed the significance of the Irish border. Accustomed to ignoring Northern Ireland, they had overlooked the fact that the UK couldn’t leave the EU customs union without reinstituting controls at the border between British Northern Ireland and EU-member Ireland, with potentially disastrous political and economic consequences.

Many Brexit proponents were attracted to the idea that the UK would no longer be subject to EU rules and could escape its bureaucracy. But to make Brexit work — for the Irish border, not least — Britain would have to stay tied to EU rules without having a say in how they are made.

Leave campaigners systematically denied this trade-off. They insisted first that the EU would cave in to UK demands. Later, they insisted that technology would solve the problem. Norgrove says he came to see it as mis-selling on a massive scale. “I was part of a systemic deliberate and desperate campaign of political lying,” he told radio host James O’Brien.

Roland Smith, another Leaver turned Revoker, argues that euroscepticism has lost its way, evolving from a healthy critique of EU processes into something like gospel. Its dirty little secret, well-hidden throughout the Leave campaign, is that the euroskeptics who became ardent Brexiters had no idea what an acceptable exit would look like. His critique is devastating.

Even if the Revoke debate doesn’t go far in Parliament, as I suspect it won’t, the second thoughts of many Britons who once favored leaving the EU are significant. Whatever happens in the weeks ahead — including a possible change of prime minister — the country’s leadership must reckon with what went wrong, and that will take courage and honesty.

Protestors unfurled a banner on Saturday quoting words spoken in 2012 by former Brexit secretary and Brexit-supporter David Davis: ‘If a democracy cannot change its mind, it ceases to be a democracy.’ The irony is that Davis had been criticising the rigidity of EU rules at the time.

Some Brexiters have changed their minds. Now, nearly three years after the vote to leave the EU, British legislators must decide whether the country has and what to do about it.

• Raphael writes editorials on European politics and economics for Bloomberg Opinion. This column does not necessarily reflect the opinion of the editorial board or Bloomberg and its owners.