WASHINGTON — Donald Trump hounded the Justice Department to pursue his false election fraud claims, striving in vain to enlist top law enforcement officials in his desperate bid to stay in power and relenting only when warned in the Oval Office of mass resignations, according to testimony Thursday to the House panel investigating the Jan. 6, 2021, Capitol riot.

Three Trump-era Justice Department officials recounted persistent badgering from the president, including day after day of directives to chase baseless allegations that the election won by Democrat Joe Biden had been stolen. They said they swept aside each demand from Trump because there was no evidence of widespread fraud, then banded together when the president weighed whether to replace the department’s top lawyer with a lower-level official willing to help undo the results.

The hearing, the fifth this month by the panel probing the assault on the Capitol, made clear that Trump’s sweeping pressure campaign targeted not only statewide election officials but also his own executive branch agencies. The witnesses solemnly described the constant contact from the president as an extraordinary breach of protocol, especially since the Justice Department has long cherished its independence from the White House and steered clear of partisan politics in investigative decisions.

“When you damage our fundamental institutions, it’s not easy to repair them,” said Jeffrey Rosen, the acting attorney general in the final days of the Trump administration. “So I thought this was a really important issue, to try to make sure the Justice Department was able to stay on the right course.”

Steven Engel, former assistant attorney general for the Office of Legal Counsel, from left, Jeffrey Rosen, former acting attorney general, and Richard Donoghue, former acting deputy attorney general, are sworn in to testify as the House select committee investigating the Jan. 6 attack on the U.S. Capitol continues to reveal its findings of a yearlong investigation, at the Capitol in Washington on Thursday.  Jacquelyn Martin/Associated Press

The hearing focused on a memorably tumultuous time at the department after the December 2020 departure of Attorney General William Barr, who drew Trump’s ire with his public proclamation that there was no evidence of fraud that could have changed the election results. He was replaced by his top deputy, Rosen, who said that for a roughly two-week period after taking the job, he either met with or was called by Trump virtually every day. The common theme, he said, was “dissatisfaction about that the Justice Department had done to investigate election fraud.”

Trump presented the department with an “arsenal of allegations,” none of them true, said Richard Donoghue, another top official who testified Thursday. Even so, Trump prodded the department at various points to seize voting machines, to appoint a special counsel to probe fraud claims and to simply declare the election corrupt.

The department did none of those things.

“For the department to insert itself into the political process this way, I think would have had grave consequences for the country that very well may have spiraled us into a constitutional crisis,” Donoghue said.

The testimony made clear that Trump did, however, find a willing ally inside the department, in the form of an environmental enforcement lawyer who’d become the leader of the agency’s civil division. The attorney, Jeffrey Clark, was introduced to Trump in late December by a Republican congressman and postured himself as willing to champion the election fraud claims. In a contentious Oval Office meeting on the night of Jan. 3, 2021, just three days before the election, Trump toyed with replacing Rosen with Clark but backed down amid threats of mass resignations,

Clark’s name was referenced early and often in the hearing, with Rep. Adam Kinzinger, an Illinois Republican and committee member, deriding him as a lawyer whose sole qualification was his fealty to Trump. A lawyer for Clark did not return messages seeking comment.

“Who is Jeff Clark?” Kinzinger asked rhetorically. “He would do whatever the president wanted him to do, including overthrowing a free and fair democratic election.”

Barely an hour before the hearing began, it was revealed that federal agents on Wednesday searched Clark’s Virginia home, according to a person familiar with the matter who was not authorized to discuss it by name and spoke on condition of anonymity. It was not clear what agents were seeking.

The latest hearing centered less on the violence at the Capitol than on the legal push by Trump to undo the election results. In one phone conversation, according to handwritten notes taken by Donoghue and highlighted at Thursday’s hearing, Trump directed Rosen to “Just say the election was corrupt and leave the rest to me and the R. Congressmen.”

Around that time, Trump was introduced by a Republican congressman, Rep. Scott Perry of Pennsylvania, to Clark, who’d joined the department in 2018 as its chief environmental lawyer and was later appointed to run its civil division. Clark has been subpoenaed by the committee but was not among the witnesses Thursday. Lawmakers on Thursday played a videotaped deposition showing him repeatedly invoking his constitutional right against self-incrimination.

Perry’s name surfaced later in the hearing, when the committee played videotaped statements from Trump aides saying that he and several other Republican members of Congress sought pardons from the president that would shield them from criminal prosecution, the testimony revealed.

Perry and fellow GOP Reps. Andy Biggs of Arizona, Mo Brooks of Alabama, Matt Gaetz of Florida and Louie Gohmert of Texas all had been involved in efforts to reject the electoral tally or submit “fake electors.” Gaetz tweeted Thursday that the hearing was a “political sideshow.”

The situation came to a head on Jan. 3, 2021, a Sunday, when Clark informed Rosen in a private meeting at the Justice Department that Trump wanted to replace him with Clark as acting attorney general. Rosen, resisting the idea of being fired by a subordinate, testified that he contacted senior Justice Department officials to rally them together. He also requested a White House meeting.

That night, he showed up at the White House for what would be a dramatic, hours-long meeting centered on whether Trump should follow through with his plans for a radical leadership change at the department. Also there was Steven Engel, another senior Justice Department and Rosen ally who testified Thursday, and Clark.

At the start of the meeting, Rosen testified Thursday, “The president turned to me and he said: ‘The one thing we know is you, Rosen, you aren’t going to do anything. You don’t even even agree with the claims of election fraud and this guy at least might do something.”

Donoghue made clear to Engel that he would resign if Trump replaced Rosen with Clark. Trump asked Engel whether he would do the same, and Engel responded that absolutely he would because he’d be left with no choice.

The president backed down. The night, and later his Republican administration, ended with Rosen still atop the Justice Department.

Donoghue also sought to dissuade Trump from believing that Clark had the legal background to do as the president wished since he was not a criminal prosecutor at the department.

“And he kind of retorted by saying, ‘Well, I’ve done a lot of very complicated appeals and civil litigation, environmental litigation, and things like that,’” Donoghue said. “And I said: ‘That’s right. You’re an environmental lawyer. How about you go back to your office, and we’ll call you when there’s an oil spill.’”

Associated Press writers Michael Balsamo, Lisa Mascaro, Mary Clare Jalonick and Farnoush Amiri in Washington contributed to this report.