Alex Brandon / Associated Press

One of the early choices every 2020 Democratic presidential contender will face is how to react the first time the audience at a campaign event breaks into the chant “Lock him up.”

That day likely isn’t far away now that prosecutors from the Southern District of New York, in Donald Trump’s own Justice Department, have formally implicated the president in two violations of campaign-finance law by Michael Cohen, his former attorney and fixer, who was sentenced to three years in jail on Wednesday.

Those allegations against Trump could add an extraordinary element of volatility to a 2020 presidential election that already looks poised to produce astronomical levels of both voter turnout and political polarization. The charges mean that, along with all the other combustible issues surrounding Trump’s presidency, another stark question could now be on the ballot in 2020: Does Trump face the risk of prosecution after he leaves the White House for actions he took to win the presidency?

Two factors are converging to ignite that debate. The first is the legal threat against Trump. In court documents last week, Cohen acknowledged his role in a 2016 plan to silence Stormy Daniels and Karen McDougal, the porn star and the former Playboy model who claimed to have had affairs with Trump, through undisclosed large payments that amounted to illegal campaign contributions. In those actions, prosecutors wrote, Cohen “acted in coordination with and at the direction of” what the documents called “Individual-1,” meaning Trump. Compounding Trump’s jeopardy, on Wednesday the publisher of the National Enquirer acknowledged that it had paid off McDougal in coordination with Trump’s campaign.

Even with those admissions, convicting Trump wouldn’t be simple, experts note: The Justice Department lost a similar case against the Democrat John Edwards when it charged him with hiding payments to his mistress in the 2008 campaign. Trump could argue that the payments were intended not to influence the campaign but to prevent embarrassment for his family, and he could also insist, as he did in a Reuters interview this week, that he assumed the maneuvers were legal because his attorney had told him so.

But despite those hurdles, with the evidence prosecutors have already collected, it is likely they would indict anyone else in Trump’s position, says Richard Hasen, a law professor at the University of California at Irvine and an expert in campaign-finance law. “On these set of facts, I would not be surprised to see an indictment,” Hasen says, “if he were not the president.”

That qualification creates the second condition for the 2020 storm. The Southern District prosecutors are unlikely to challenge the Justice Department’s previous determinations that a sitting president can’t be indicted. That means Trump could not be prosecuted until he leaves office. Since the statute of limitations on the campaign-finance violations expires in 2021, voters likely will go to the polls in 2020 knowing that if Trump is defeated, he could face trial and conceivably (though less likely) jail time, and that if he wins four more years, he’s home free. If Special Counsel Robert Mueller’s investigation ultimately accuses Trump of any crimes, a similar equation might apply.

Republicans, characteristically, have already signaled they will shrug off the campaign-finance allegations against Trump. In 2018, Republicans were swept from their House majority—Democrats won the total House popular vote by a greater margin than the GOP did in its 1994 and 2010 landslides—in part because voters felt they would not constrain or limit Trump. Yet Republicans have universally dismissed these new charges against Trump. In the process, they have again provided Democrats a resonant symbol that a Republican Congress will not impose any accountability on Trump, no matter the provocation. In 2020, that argument could prove as powerful in such places as Maine and Colorado, two Democratic-leaning states where Republicans are defending Senate seats, as it did in white-collar suburban House districts nationwide in 2018.

Democrats face more nuanced decisions. Democratic audiences are sure to press the 2020 candidates, once they start announcing early next year, to indicate whether they would prosecute Trump if they beat him. It won’t be too long until a crowd in Iowa or New Hampshire flips the gender in Trump’s derisive chant about Hillary Clinton, “Lock her up!”

At that point, Democrats will face a choice that some strategists believe could provide one of the campaign’s first defining moments. Do they suppress the chant? Join in? Find a middle ground? One top strategist for a potential top-tier Democratic candidate, who asked not to be identified so as to discuss internal strategy, said that in such a crowded field, it’s inevitable that some candidates will target the progressive base by promising to pursue Trump. “Someone looking for attention is going to set a bar on this,” the strategist said.

But Neil Sroka, communications director for the grassroots liberal group Democracy for America, predicts that progressives won’t pressure Democrats to echo Trump’s belligerent threats against Clinton, which have continued since he took office. “I could see a really powerful moment … when a chant of ‘Lock him up’ emerges from the audience, a candidate stepping back and saying, ‘No, this is what makes us different from the other side,’” Sroka said.

Instead, Sroka said, grassroots liberals will push the candidates to promise a full investigation of all the legal questions surrounding Trump, but not demand a preemptive pledge to prosecute him. Barack Obama essentially struck that balance in 2008 when he faced demands during the Democratic primaries to investigate the use of torture against suspected terrorists under his predecessor, George W. Bush.

Ultimately, Obama’s Justice Department, after several investigations, did not prosecute anyone over Bush’s brutal interrogation policies. That decision reflected the long-standing reluctance in both parties to escalate political disputes into courtroom trials. Trump, who has shredded so many other political norms, has to hope that one survives if voters unseat him two years from now.

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