Boris Johnson, the former London mayor and an outspoken champion of the United Kingdom’s departure from the European Union, has emerged as the front-runner to replace outgoing British Prime Minister Theresa May. The outcome could add chaos to the already uncertain withdrawal process, according to Mai’a Cross, an associate professor of political science and international affairs at Northeastern.

May, who is a member of Britain’s Conservative party, will be replaced in July by either Johnson or Jeremy Hunt, following a vote by the roughly 160,000 members of May’s party. Whoever takes the office will be in charge of coordinating the U.K.’s divorce from the E.U., a process known as Brexit. And it’s likely that Johnson—a popular figure among Conservatives and the leader in the race—will be that person, says Cross, whose research focuses on international cooperation and European foreign policy.

The decision to leave was born out of a June, 2016 referendum, in which citizens of the U.K. narrowly voted to withdraw from the European Union. 

The vote was so narrow, in fact, and the process so uncertain, that a new poll released this week by Northeastern University and Gallup shows that a majority of U.K. residents would oppose Brexit and support the U.K. remaining a member of the E.U., if they were given the chance to vote again in a new referendum.

For now, no such referendum is planned, and Johnson was a vocal advocate for leaving the E.U., a position he’s maintained throughout numerous delays as British and European leaders failed to agree upon a plan for leaving. The most recent extension by the E.U. gives the U.K. until Oct. 31 to come up with a plan to leave.

Johnson has said he would leave on Oct. 31 with or without a plan—a scenario nicknamed a “no-deal Brexit,” or a “crash-out Brexit.” But he added this week that he considers the odds of a no-deal Brexit are “a million-to-one against.”

 A no-deal Brexit would leave the U.K. scrambling to figure out the country’s trade relationship with Europe and the rest of the world, says Cross, who is the Edward W. Brooke Professor of Political Science at Northeastern. It would mean uncertainty over how to address the U.K.’s only land border, between Northern Ireland and the Republic of Ireland, which comes with a violent history.

The way Johnson chooses to govern the U.K. toward leaving the E.U., should he be elected prime minister, could trigger even further chaos in the country, Cross says. 

 A number of the members of parliament are prepared to “toss up roadblocks” should Johnson guide the country toward leaving the E.U. without a plan, Cross says. One such roadblock is the inclusion of an amendment to any bill introduced by Johnson that would prevent the country from crashing out, Cross says.

Such an amendment could be made to any bill at all, even if the bill itself has nothing to do with Brexit, Cross says.

“Boris Johnson would be quite aware of this,” Cross says, “so he might not introduce any bill at all in order to avoid it.”

The only way for Johnson to avoid such a measure is for him not to introduce any bills at all between when he would take office on July 24, and the new Brexit deadline of Oct. 31, Cross says.

“If he really wanted to ram through a no-deal Brexit, he’d have to not govern from July to October,” Cross says. “It would be a really bad situation.” Pausing, she adds, “I don’t even know how to articulate it, that’s how bad it would be.”

If the U.K. crashes out of the E.U., it would be thrust out of collective economic and law enforcement arrangements overnight. The U.K. would suddenly be subject to trade terms set by the World Trade Organization, which would immediately create new tariffs on goods.

“Big industries like the automobile industry could face bankruptcy very quickly in that case,” Cross says.

Among the bills Johnson wouldn’t be able to introduce are those to safeguard the country against the damage of such a sudden departure from the E.U., Cross says. Johnson couldn’t pass any bills that would protect business owners from the new tariffs that would be introduced literally overnight if the U.K. leaves the E.U. without any kind of transition period.

“Just the very notion that your government isn’t running from July to October is very destructive symbolically,” Cross adds. “It’s potentially damaging to the country.” 

For media inquiries, please contact Shannon Nargi at s.nargi@northeastern.edu or 617-373-5718.