A Florida lawyer is challenging former President Trump’s ability to run for president in 2024 under the U.S. Constitution’s 14th Amendment, citing the Jan. 6, 2021, Capitol attack.

Lawrence Caplan, a tax attorney in Palm Beach County, filed the challenge in federal court Thursday, pointing to a clause in the amendment that says those who “have engaged in insurrection or rebellion” against the government cannot hold office.

The challenge was first reported by The Palm Beach Post.

“The bottom line here is that President Trump both engaged in an insurrection and also gave aid and comfort to other individuals who were engaging in such actions, within the clear meaning of those terms as defined in Section Three of the 14th Amendment,” Caplan wrote in the filing. “Assuming that the public record to date is accurate, and we have no evidence to the contrary, Trump is no longer eligible to seek the office of the President of the United States, or of any other state of the Union.”

Caplan’s challenge is one of the first questioning the legality of Trump’s 2024 bid, though Trump is also facing criminal charges at both the state and federal level over his actions to undo the results of the 2020 vote.

The former president is currently the far-and-away front-runner in the GOP presidential primary. A spokesperson for his campaign told The Hill that the lawsuit has “no basis in fact or law.”

“We look forward to its prompt dismissal, to an award of legal sanctions against the plaintiff and to receiving full payment from him of all of our legal fees responding to this meritless, bad faith case,” the spokesperson said in a statement.

In an interview with The Hill, Caplan said that “someone had to take the lead” on challenging Trump’s candidacy.

“This is a scary, scary guy, and if he’s president, I think we’re all on the way to fascism,” he said. “There’s no law that says we have to remain a democracy forever.”

In the filing, Caplan wrote that the facts of his case “are undeniably simple.” In 2016, Trump won the presidential election, and in 2020, he lost it. The following Jan. 6, Trump encouraged a throng of supporters to march to the Capitol, saying he’d be “right there with them,” Caplan wrote.

“As we are well aware, the throng marched on the Capitol, forced their way into the Capitol building, ransacked the rotunda area, and even made their way into several offices of representatives and senators,” he wrote.

The 14th Amendment’s “disqualification clause” was written in the context of the Civil War, meant to bar those who had joined the Confederacy from serving in state or federal office. But it would “theoretically still apply” to those who engage in future rebellions or insurrections against the U.S., according to Cornell University’s Legal Information Institute.

Caplan told The Hill that he did not originally believe Trump’s role in the Capitol attack could disqualify him from becoming president again. That changed when he read an analysis by former 4th Circuit Appeals Court Judge J. Michael Luttig and Harvard legal scholar Laurence Tribe.

In an article published last week in The Atlantic, Luttig, a conservative, and Tribe, who is liberal, contended that Trump’s efforts to remain in power after losing in 2020 “place him squarely within the ambit of the disqualification clause.”

Trump’s grand jury indictments in the Washington, D.C., federal case and the Georgia case probing those efforts make his disqualification automatic, Caplan said.

Trump surrendered to authorities on the Georgia charges Thursday evening, becoming the first former U.S. president to have a mug shot taken.

“The common sense of it is that the law says that someone who’s indicted for causing an insurrection is automatically ineligible to run for federal office,” Caplan told The Hill.

Whether the Capitol attack rises to the level of an insurrection under the law is a question still hotly debated among both legal scholars and politicians.

In his filing, Caplan wrote that “one can certainly argue” that the clause has not been “thoroughly tested.” But he countered that is only because the U.S. has not otherwise “faced an insurrection against our federal government such as the one while we faced on January 6, 2021.”

Caplan told The Hill on Friday that he is not an “overtly political person.” He said his first job out of law school was working for the National Security Agency — “so nobody could say that I’m not a patriot” — and that he has voted for Republicans in the past.

“The law is the law,” Caplan said. “We’ll see whether or not the judges have the guts to follow the law.”

Updated: 9:59 on Aug. 28