We spoke to the man behind the Brexit legal case which could open the door to a second referendum

LONDON - Jolyon Maugham, the man behind a fresh Brexit legal challenge, says the public should be given the chance to reverse Britain's departure from the EU if there is a substantial shift in popular opinion.

Business Insider interviewed the London-based barrister on Thursday to discuss his crowdfunded legal case, which will ask the Irish High Court to decide whether Article 50 can be revoked once it's been triggered by UK government.

The case, which Maugham expects to be officially filed before Christmas, will then be referred to the European Court of Justice, where EU judges will be asked to rule whether Theresa May is able to revoke Article 50 once it's invoked.

The legal question posed by Maugham is a crucial one.

If Article 50 revocable, then it gives rise to the possibility of MPs rejecting the terms of any Brexit deal the prime minister secures in the two-year negotiation period, as Britain's formal departure would no longer be inevitable.

This, in turn, would increase the chances of another referendum taking place, only this time on the terms of Brexit.

"The Article 50 case raises a legal question," Maugham tells us. "Can Article 50 can be revoked? The political question - does the government want to revoke? - is a question for the government. It's a question for democratically elected MPs in the UK elected by UK constituencies. They will have the final say.

"Government has proceeded on the premise that Article 50 may be revocable. When David Davis was asked in the Commons he said 'we won't revoke it' which is a very different answer to 'it is incapable of being revoked' - he gave a political answer, not a legal one. My suspicion is the advice the government has had is that Article 50 is revocable."

A second referendum must remain an option

Speaking to us in central London, Maugham said that the June 23 vote should be respected but argued that there would be a democratic deficit if no way out was available to the public if a significant change in mood takes place.

"My view is that the referendum requires that parliament triggers Article 50. I recognise the democratic force of the vote the electorate made on June 23. Whether or not there should be a second referendum on the final deal we strike with Brussels depends upon essentially whether peoples' attitudes remain static between now and the date when the agreement is concluded or whether they change. If they remain static, then I don't think it'd be appropriate to have a second referendum.

"If, on the other hand, the predictions of Remainers that the economy will suffer prove to be true and the electorate begins to feel that perhaps Brexit is not such a good idea after all and they were wrong in following the advice of the Leave campaigners to ignore the forecasts as mere 'Project Fear', then polling data clearly shows that people would rather not Brexit.

"It would be terrible if the British people were to be told two years from now that although they desperately don't want Brexit they have to have it anyway."

"You might compare it to somebody who is presented with an estate agents' particulars promising a splendid little cottage in the country and you go there on the basis of those particulars. If it's the same as the particulars then perhaps you buy it. But as we know, when you get there it's often encircled by an eight-lane super-highway that the estate agent didn't mention, and once you appreciate the reality of the situation your initial instinct alters.

He added: "Now, it would be terrible if the British people were to be told two years from now that although they desperately don't want Brexit they have to have it anyway. I think we as politicians, we as media, we as campaigners, have an obligation to unlock the door to the people having another say if that's what they decide they want."

This case is the latest in a series of legal challenges relating to Britain's exit from the EU. The Gina Miller case will reach a conclusion next month when the Supreme Court judges rule whether May must secure parliamentary approval before triggering Article 50.

He won't be deterred by abuse

Miller has received waves of abuse since first launching the case, including death threats which drove her to hire bodyguards ahead of the Supreme Court case taking place. Maugham says he has already been subject to threats online, but won't be deterred from pursuing the case.

"I've received abuse. I've received what looked like threats. I haven't reported these threats to the police but I know that the police are investigating them because others have complained, but not at my instigation. Am I complacent? No, I am not. If the situation develops I may need to engage security but I do not yet think that I am that place.

"I don't have any intention of being deterred."

"That having been said, my life has been made much more difficult in lots of ways. For example, I woke up on Monday morning and discovered that overnight someone had subscribed my work email to 500 new email subscription lists, which has made it very difficult to operate. I've had to close down the comment section because somebody set up a bot to repeatedly post very colourful language.

"I don't doubt that there will be more of this in the future. But will it deter me? The funny thing is, if a Brexit supporter was sitting in this seat, he or she would tell you that they feel incredibly passionate that this is the right thing to do for their country. I am sitting in this chair telling you that I feel that it's the right thing to do as well.

"I don't have any intention of being deterred."

Article 50 may have been triggered already

One fascinating detail in the case Maugham has launched is the argument that Article 50 may already have been triggered. The prime minister has pledged to initiate Britain's exit from the EU in March next year, but the lawyers in Maugham's case intend to raise the point that the two-year withdrawal may already be underway.

"If you look at the terms of Article 50 itself, one of the terms is there has to be a decision and there has to be notification. The government's position is there has been a decision. So, what you're left with is the requirement that there be notification. We know that in October Theresa May met with her fellow leaders at an EU council meeting and told them we were leaving. Now, there's no requirement in Article 50 that notification must be served on heavy watermarked paper. There is no requirement for formality at all.

He adds: "If you then cast your net more widely and you look around at the surrounding circumstances, you can see that the EU are now meeting privately without us. Article 50 says this is something that is not supposed to happen until after we have triggered it. If you look at the fact that the EU has appointed negotiators - that's something that's not supposed to happen until after we have triggered Article 50. If you look at the fact they've formulated their negotiating strategy - that's something that shouldn't happen until after you trigger Article 50.

"And finally, just the other day Michel Barnier said that the discussions needed to be concluded by October 2018 because member states would need to vote on the deal that was being offered. October 2018 is two years from the date that this claim suggests Article 50 may have been notified on. If you look at the surrounding context, this idea that was initially counterintuitive begins to acquire at the very least the quality of being arguable. It's not my notion, it's a notion that's been put forward by the lawyers in the case and it's a point that at present we intend to take."

Maugham crowdfunded £70,000 in no more than 36 hours in order to launch this case, with 1,300 donations of £25 or less. It's a case that has already attracted media attention and will only grow in status as it enters the Irish Court, which Maugham expects to happen in March. "This is an incredibly important moment in the history of our nation," he said. "We are entitled to understand the legal framework in which we are operating because on the basis of that framework decisions will be made which will affect people in this country for generations to come."