(WASHINGTON) — The House select committee investigating the Jan. 6 attack on the U.S. Capitol is set to bring into focus Thursday former President Donald Trump’s relentless post-Election Day efforts to enlist the Justice Department in his failed bid to overturn his election loss.

The committee’s fifth hearing this month will feature testimony from three former top officials in the department who say they resisted Trump and his allies’ repeated entreaties, former acting attorney general Jeffrey Rosen, former deputy acting attorney general Richard Donoghue and former top DOJ lawyer Steven Engel.

All three have previously confirmed that they went as far as joining a group of top White House lawyers in threatening a mass resignation if Trump didn’t back away from plans to oust Rosen and replace him with another obscure official in the top echelons of the department who was sympathetic to the president’s baseless claims of widespread voter fraud.

That former official, Jeffrey Clark, previously pleaded the Fifth Amendment in an appearance before the committee and has declined to comment through an attorney when asked about specific details regarding his alleged coordination with Trump and others.

Trump ultimately relented, and his behind-the-scenes campaign wasn’t publicly revealed until the New York Times reported on the dramatic standoff several days after President Joe Biden’s inauguration.

Throughout his four-year tenure, former President Trump completely disregarded and distorted Justice Department protocols in place since the post-Watergate era, where the department sought to generally avoid having the White House or the president directly involved in criminal matters.

Trump’s efforts following his loss to Biden blew up any notion of Justice Department independence on criminal investigations that might benefit the White House or president politically. Trump’s post-election interaction with top DOJ officials portray a president pressing for specific investigations that could potentially help him keep his grip on power.

And FBI and DOJ investigators did indeed end up investigating some of the more outlandish claims pushed by Trump election lawyers like Rudy Giuliani, John Eastman and others.

Similar to the committee’s first two hearings revealing evidence gathered from their nearly year-long investigation, much of the details of Trump’s effort to weaponize DOJ in his effort to undermine the results of the election have been reported on previously.

In remarks last week, the committee’s vice chair Rep. Liz Cheney, R-Wyo., said the hearing will seek to tie Trump’s effort to “corrupt the Department of Justice” into his broader plan to thwart the certification of Biden’s victory on Jan. 6, which culminated in the deadly attack on the Capitol.

ABC News has learned that Rosen on Thursday will testify that he was under repeated and constant pressure from Trump to find widespread corruption.

A source familiar with the matter told ABC News that Rosen would often simply reply to the president that his department was “just not seeing the evidence.”

The source said that at one point Clark discussed with Rosen that the president was about to name him acting attorney general and that Rosen could potentially stay on as Clark’s deputy. The source said Rosen used that information to coordinate with other department officials a plan of mass resignation if Trump were to remove him and install Clark.

In August last year, ABC News exclusively obtained emails showing how Rosen and Donoghue rebuffed Clark’s request to urge officials in Georgia to investigate and possibly overturn Biden’s victory in the state.

The emails showed a draft letter circulated by Clark on Dec. 28, which he sought to send to Georgia’s governor and other top state officials, advising them to convene the state legislature into a special session so lawmakers could investigate claims of voter fraud.

“There is no chance that I would sign this letter or anything remotely like this,” Donoghue responded roughly an hour after receiving Clark’s email. “While it maybe true that the Department ‘is investigating various irregularities in the 2020 election for President’ (something we typically would not state publicly) the investigations that I am aware of relate to suspicions of misconduct that are of such a small scale that they simply would not impact the outcome of the Presidential Election.”

Rosen responded several days later on Jan. 2, according to the emails, stating he had “confirmed again today that I am not prepared to sign such a letter.”

A day later, according to previous testimony from Rosen and Donoghue to both the Senate Judiciary Committee and House select committee, came the extraordinary meeting in the Oval Office.

Rosen said he arranged for the meeting through Trump White House chief of staff Mark Meadows after learning from Clark that Trump planned to replace him “so that [Clark] could pursue” his plan with the Georgia election.

“And I said “Well, I don’t get to be fired by someone who works for me,” in the case of Mr. Clark. I wanted to discuss it with the President,” Rosen told Congress last year.

That night, Meadows walked Rosen, Donoghue and Engel into the meeting with Trump, Clark, then-White House counsel Pat Cipollone and his top deputies — but Meadows then left the room for the discussion that followed, according to Rosen.

“The president said something near the very beginning, “One thing we know is you, Rosen, aren’t going to do anything. And you don’t even agree that I’m right about these concerns that people are telling me,”” Rosen recalled Trump saying.

What followed was a roughly two-and-a-half-hour meeting, by Rosen and Donoghue’s telling, where Trump repeatedly pressed but was eventually dissuaded from his plan to install Clark atop the Justice Department to pursue baseless allegations of voter fraud just days before Congress was set to convene to certify Biden’s victory.

What appeared to change Trump’s mind, according to Donoghue’s testimony, was unanimity among nearly everyone in the room that they would resign if Trump moved forward with the plot.

“And I said, “And we’re not the only ones. You should understand that your entire Department leadership will resign,” Donoghue said. “And I said, “Mr. President, these aren’t bureaucratic leftovers from another administration. You picked them. This is your leadership team. You sent every one of them to the Senate; you got them confirmed. What is that going to say about you, when we all walk out at the same time?”

Donoghue then detailed a nightmare scenario for Trump of hundreds of career officials in the department following en masse, resignations that he said Engel told Trump would leave Clark “leading what he called a graveyard; there would be no one left.”

The account of the Jan. 3 meeting could prove for gripping on-camera testimony as the committee seeks to show the country that the former president, desperate at clinging to power by any means necessary, was in the days leading up to Jan. 6 seriously entertaining a plot that would almost certainly thrust the country into an unprecedented constitutional crisis.

Rosen, Donoghue and Engel could also serve to bolster the committee’s line of argument that President Trump was persistent in moving forward with his attempt to overturn the election leading up to Jan. 6, even as he had been told repeatedly that he had lost.

While much of the focus thus far on that front in the committee’s investigation has zeroed in on Barr’s private statements to Trump as well as in an interview with the AP about the department finding no evidence of fraud that could overturn the election results, his resignation left a clear opening for Trump to continue seeking to use the department to aid his campaign to overturn the election.

Rosen has previously testified that at a meeting on Dec. 15, the day after former attorney general William Barr announced he would resign from the department, a group of top officials at the White House told Trump that “people are telling you things that are not right” regarding claims of widespread fraud in the election.

Donoghue said he later told Trump in a Dec. 27, 2020 phone call “in very clear terms” that DOJ had done “dozens of investigations, hundreds of interviews” and determined “the major allegations are not supported by the evidence developed.”

And unlike Rosen, Donoghue and Engel — Barr’s statements to the committee about his private interactions with Trump appear in direct conflict about his public actions leading up to his resignation.

Leading up to the 2020 election, Barr spent more time arguably than any other Trump cabinet official sowing doubts about expansions of mail-in voting, laying the groundwork for Trump and his legal team to later make their baseless claims of widespread voter fraud.

Barr pushed a conspiracy theory that foreign actors would be able to flood the country with millions of fraudulent ballots, even when top officials in the intelligence community were publicly disputing that was possible.

Barr told ABC News Chief Washington Correspondent Jonathan Karl in an interview that then-Senate Majority Leader Mitch McConnell had been urging him to speak out against Trump’s fraud claims “since mid-November,” in part over McConnell’s fears it would sabotage the GOP’s chances to win the Georgia Senate runoffs. Barr didn’t give his interview ruling out widespread fraud to the AP until Dec. 1.

But two weeks later, Barr gave his resignation letter to Trump, saying he “appreciate[d] the opportunity to update you this afternoon on the Department’s review of voter fraud allegations in the 2020 election and how these allegations will continue to be pursued.” The resignation letter showed no indications of Barr’s supposed concerns about Trump’s behavior, and instead lauded Trump as a victim of a supposed left-wing-led conspiracy to undermine all the accomplishments of his administration.

The Justice Department’s inspector general last year announced it had launched its own investigation into efforts inside the department to subvert the 2020 election.

Attorney General Merrick Garland, who is currently overseas, told reporters at the Justice Department last week that he plans to watch all of the committee’s hearings in their entirety, while adding, “I can assure you that the January 6 prosecutors are watching all of the hearings as well.”

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