Shahmir Sanni, a former Brexit campaigner, at the Frontline Club in London on March 26, 2018. (Henry Nicholls/Reuters)

If he knocked on your door, Shahmir Sanni might not be what you would expect of a campaigner for Brexit, Britain’s historic — now wrenching, all-consuming — decision to leave the European Union.

Sanni is a young, hip, gay Muslim, a Pakistani Briton who studied economics at his university, loves fashion and is an American-style libertarian, a committed “Euroskeptic.” He does not want less immigration to Britain; he wants more. But he wants London, not Brussels, to be in control. He describes himself as “sassy.”

Once an anonymous college-age volunteer, Sanni is now front-page news in Britain as a whistleblower who alleges that pro-Brexit campaigners in 2016 “cheated” — specifically, that a prominent group run by top Conservative Party figures, including now-Foreign Secretary Boris Johnson, broke election law by coordinating campaigns among allied organizations to circumvent spending caps.

The political firm at the center of the controversy is Aggregate IQ, a tiny Canadian firm closely connected to Cambridge Analytica, which ran President Trump’s winning digital campaign and is at the heart of a Facebook data-sharing scandal that has cost the platform giant $80 billion in market value.

The week-long controversy over who did what and how in the 2016 Brexit vote quickly ensnared Prime Minister Theresa May and her inner circle. 

One of May’s senior aides at 10 Downing Street, Stephen Parkinson, was a top Brexit campaigner. He is also Sanni’s former boyfriend — and is accused of publicly outing Sanni as gay.

Sanni branded it revenge, an attempt to silence him. 

He said his outing could endanger family members in Pakistan, where Sanni said homosexuality remains taboo, especially in conservative circles. He had to rush to come out to his mother, who lives in London. “The worst day of my life,” he told The Washington Post.

Parkinson said the revelation was exculpatory and necessary. In his statement, he said he did nothing wrong and only advised Sanni as a friend, not as a co-campaigner. 

May defended her aide in Parliament, stressing that his statement was “personal,” though the email sent to reporters by May’s press office included a subject line with the word “official” in capital letters.

The accusation of questionable campaign coordination and spending has been dismissed as a “lover’s quarrel” and a total nothingburger. It has also been hyped as a bombshell that calls into question not only the decision to leave the European Union, but also Britain’s fair play and democratic values.

In the closing days of the 2016 Brexit campaign, Sanni and his friend Darren Grimes zoomed from being unpaid part-time volunteers for the main “Vote Leave” organization, fronted by Tories Johnson and Michael Gove, to becoming leaders of their own allied group, called “BeLeave.” 

Sanni and Grimes were both 22, and this was their first political campaign. They did outreach but had limited numbers of online followers and email addresses of supporters. 

“We were enthusiastic, committed, and we thought we were brilliant,” Sanni said. “But I think we were used.”

Although British law bans coordination between campaigns, Sanni said he and Grimes were based in the Vote Leave headquarters; were advised by Vote Leave staffers, including May’s now-senior adviser; and relied on Vote Leave’s attorney, who helped them incorporate the BeLeave group.

Sanni said that after he was instructed to set up a bank account, BeLeave learned it would be getting a donation of $878,000 via the Vote Leave organization, which was running up against campaign spending limits. However, the money never went into the BeLeave account, Sanni said. Instead, he said, it went directly to Aggregate IQ to blast voters in the last week of the campaign with targeted messages on social media.

Aggregate IQ was doing similar work for the Vote Leave campaign, according to campaign finance reports first published by BuzzFeed in the aftermath of the referendum.

Christopher Wylie, a former research director for Cambridge Analytica who has become a whistleblower, testified before the British Parliament’s media committee that he helped set up Aggregate IQ and that it mixed funding and work for Vote Leave and BeLeave in violation of election laws.

“If we allow cheating in our democratic process . . . what about next time? What about the time after that? This is a breach of the law,” Wylie told Parliament.

In statements, Aggregate IQ said it did nothing wrong and had followed the law.

Vote Leave’s campaign director, Dominic Cummings, declined an interview request, but on his blog, he wrote that the whistleblowers had “promised Watergate and delivered a dodgy Zoo­lander.”

He wrote, “Vote Leave’s donations were legal, the Electoral Commission gave us written permission, the whistleblowers are provably lying, we leave in a year and this lame gossip won’t even be a historical footnote.”

Johnson, the foreign secretary, called accusations of illegal coordination “utterly ludicrous.”

“Vote Leave won fair and square — and legally,” Johnson tweeted.

In debate in Parliament, lawmakers were divided over alleged breaches of electoral law.

Labour lawmaker Ben Bradshaw said that when he began raising concerns about the Brexit vote, he was considered a “crank.” But now, he said, almost all of his allegations have “proven to be correct.”

He said, “It’s not about who won or lost the referendum; it’s about the integrity and security of our democracy and our electoral system.”

Bradshaw added that it was “disgraceful” that May’s political secretary had outed Sanni as gay. “I’m amazed that that man is still in his job. That’s totally unacceptable.” 

Concluding the debate, government minister Chloe Smith said she would not comment on allegations that are under investigation. She added that the Electoral Commission, the official watchdog, had concluded that the Brexit vote was delivered without any major issues and that the government would implement the results.

Political analysts said the accusations of financial cheating will be a boost to the pro-Europeans keen to cast doubt on the legitimacy of the Brexit referendum, in which Britons voted 52 percent to 48 percent in favor of leaving the European Union.

“It helps keep a second referendum on the agenda, but it’s not going to be the thing that actually triggers that referendum,” said Tim Bale, a politics professor at Queen Mary University of London. “The only thing that’s actually going to trigger that referendum is MPs in Parliament feeling that the deal is a disaster and that public opinion is beginning to shift.” 

He said claims that the Brexit vote may have been won through fraud were probably overstating the case. 

“The feeling still is that Leave would have won even without any tampering going on,” he said.