(The Hill) — An effort to use the legal system to bar former President Donald Trump from returning to the White House — on the basis that he aided an insurrection on Jan. 6, 2021 — is picking up speed.

Proceedings began before the Minnesota Supreme Court on Thursday, while a separate but similar case has been running in Colorado since Monday. Other broadly comparable efforts are at earlier stages in other states.

The idea that the front-runner for the Republican nomination could be thrown off the ballot may seem outlandish on its face.

But it has begun to seem less so. For example, an effort by Team Trump to get the judge in Colorado to throw out the case has failed. 

Here are the big things to know.

What’s the core of the case?

The idea of barring Trump from holding office is based on the 14th Amendment.

Section 3 of the amendment notes that no one can hold office if, having previously done so and taken an oath to uphold the Constitution, they “have engaged in insurrection or rebellion against the same, or given aid or comfort to the enemies thereof.”

To Trump critics, it’s an open-and-shut case, though it’s worth noting that those who hold this view are mostly, but not exclusively, liberal.

The former president, these voices contend, encouraged the Capitol insurrection by his words and actions. Those include repeated, false claims of election fraud as well as his speech at the Ellipse on Jan. 6, in which he contended that people had to “fight like hell” to overturn the election result or “you’re not going to have a country anymore.”

In scholarly circles, the argument got a big boost when a paper emerged in August from two members of the Federalist Society, a prominent conservative legal group.

William Baude of the University of Chicago Law School and Michael Stokes Paulsen of the University of St. Thomas Law School argued that the amendment, which dates back to the Civil War era, “remains an enforceable part of the Constitution.”

They added that the amendment “in particular … disqualifies former President Donald Trump, and potentially many others, because of their participation in the attempted overthrow of the 2020 presidential election.”

What do Trump’s defenders say?

Unsurprisingly, they reject this analysis completely.

In court, lawyers for Trump’s team have made multipronged arguments, including that his actions in and around Jan. 6 were protected by the First Amendment; that they did not, in any event, amount to supporting an insurrection; and that the courts should not be in the business of superseding the will of the voters.

Only one person appears to have been barred or ejected from office since Jan. 6 on the basis of the 14th Amendment — a county commissioner from New Mexico named Couy Griffin, who was booted by a state district court judge in September 2022.

Crucially, however, Griffin had been found guilty of entering a restricted area during the Jan. 6 riot. Trump has not been found guilty of any criminal offense pertaining to Jan. 6 — so far.

A judicial intervention on the topic would be massively controversial.

What would happen if the courts found against Trump?

Chaos, probably.

The most straightforward scenario is one in which Trump’s name is kept off the ballot in states where the courts hold he is ineligible to serve.

But there are two complications.

First, Team Trump would be sure to appeal, and legal scholars believe the case would go all the way to the Supreme Court. A conservative-leaning court, in which three justices were nominated by Trump, would then be deciding his fate. 

Second, such a finding by state courts could create a bizarre patchwork, assuming Trump becomes the GOP nominee. In a presidential election, the name of a major-party nominee would be on the ballot in some states but not in others.

Minnesota Chief Justice Natalie Hudson raised this specter Thursday, according to an ABC News report.

Hudson warned of a scenario of “potentially 50 different states who, depending on the nature of the statutes in those states, [are] deciding this question differently.”

Political observers have also noted that the two states where the cases have reached the courts are ones in which Trump was defeated in both 2016 and 2020. 

Hypothetically — but plausibly — he could be kept off the ballot there yet win the presidency through the results from other states.

Is there any other way Trump could be legally blocked?

Technically, yes — maybe.

The two Federalist Society experts contend that the relevant section of the 14th Amendment is “self-executing.”

In layperson’s terms, this argument holds that the bar can take effect regardless of Trump’s lack of criminal conviction and without the need for a judge’s ruling. 

Officials whose duties include the conduct of elections — the secretary of state, usually — could simply strike him from the ballot.

There are big misgivings about this theory. 

An article in The Atlantic that was supportive of the legal case for barring Trump nonetheless quoted a Stanford law professor, Michael McConnell, who worried that “we are talking about empowering partisan politicians such as state Secretaries of State to disqualify their political opponents from the ballot … If abused, this is profoundly anti-democratic.”

So far, state secretaries of state have shown no enthusiasm for the idea, presumably because it would put them at the center of a national constitutional maelstrom.

What does Trump have to say about it all?

The former president has been more focused on his four criminal cases.

But last month, he told conservative commentator Dan Bongino that the 14th Amendment-based cases were “nonsense.”

He also contended that his foes were bent upon “election interference” worthy of a “Banana Republic.”