Rep. Liz Cheney told an attentive hearing room Tuesday that the House committee investigating the Jan. 6 insurrection vows to uncover “every minute” of what happened at the White House that day.

“Every phone call, every conversation, every meeting leading up to, during, and after the attack,” Cheney explained.

A change in Justice Department policy this week may help them do just that.

After the department announced Monday it wouldn’t block testimony from former government officials, legal experts said the committee will have a strong case to compel testimony about who organized the attack, who financed it and how the government responded.

But even as the chairman of the House committee, Rep. Bennie Thompson, D-Miss., moves briskly to issue subpoenas, legal experts caution that former administration officials could fight them in court for years.

“As soon as the subpoenas are served, they will be challenged,” said Jimmy Gurulé, a University of Notre Dame law professor and former Justice official. “I would expect this to be litigated for some time on a range of issues, from claims that the subpoenas are too broad or unduly burdensome for the testimony or documents being sought.”

Part of the investigation will focus on what former President Donald Trump was doing as rioters violently breached the Capitol and ransacked offices on live television. Lawmakers urged Trump to call off the mob.

Potential witnesses include lawmakers and the officials they contacted at the White House, Pentagon or other federal agencies.

Five people died from the melee – including a woman shot by police while trying to enter the House chamber – and about 140 police officers were injured. Other committees stitched together timelines, but found discrepancies such as a three-hour gap between the request and arrival of National Guard reinforcements.

Cheney of Wyoming, the committee’s top Republican, said the American people deserve the full and open testimony of everyone who knows about the planning and participation for the attack.

“We must know what happened here at the Capitol,” Cheney said at the committee’s first hearing with four police officers who defended the building. “We must also know what happened every minute of that day in the White House.”

Who could testify?

Lawmakers have already called for testimony from Trump, who exhorted the crowd and diminished the seriousness of the attack; former Vice President Mike Pence, whose life was threatened by rioters and who called Acting Defense Secretary Christopher Miller for help; House Minority Leader Kevin McCarthy, R-Calif., and Rep. Jim Jordan, R-Ohio. McCarthy and Jordan spoke with Trump that day as the building was under siege.

Thompson said he would begin issuing subpoenas because starting with letters seeking voluntary testimony would take too long. The committee would like to know who participated, financed, encouraged and orchestrated the attack, he said.

“The investigation is going to go wherever it may lead,” Cheney said. “Obviously the events at the White House are the focus of what went on.”

McCarthy and Jordan each spoke with Trump on Jan. 6. Each has said they would testify, but McCarthy has said his call with Trump won’t answer why the Capitol was unprepared for the attack.

“When I called the president, I was telling about what was happening in the Capitol because none of you would know unless you were in the Capitol,” McCarthy, who wanted resources brought as fast as possible, said Thursday.

“If they call me, I got nothing to hide,” Jordan told CNN.

Sen. Lindsey Graham, R-S.C., said he called Ivanka Trump, the former president’s daughter and senior adviser, during the attack.

Sen. Tommy Tuberville, R-Ala., has said he spoke to Trump to notify him that Pence had been evacuated. Sen. Ben Sasse, R-Neb., said he called White House officials.

Lawmakers have also sought answers about the preparation for and response to the attack by Trump’s Cabinet secretaries such as Miller at Defense and Chad Wolf, former acting secretary of Homeland Security.

Former Acting Attorney General Jeff Rosen told lawmakers at a May 12 hearing that he met Jan. 3 with Trump and didn’t speak with Trump on Jan. 6. But in response to questions about whether Trump pressed him to investigate election fraud, Rosen refused to describe the conversations.

Paul Rosenzweig, a former Whitewater senior counsel who investigated the Clinton administration, said he would like to know “all sorts of stuff about the White House response.”

“What did they say? I don’t know,” said Rosenzweig, founder of Red Branch Consulting.

Justice Department will allow testimony from Trump officials

The Justice Department announced Monday that former administration officials could testify, a stark change under Attorney General Merrick Garland from former Attorney General William Barr.

Without the department blocking testimony, as happened repeatedly during the impeachment investigations of Trump, former officials who defy their subpoenas will have to pay for their own court battles.

The department said it will not assert executive privilege for officials such as Rosen because the issues under investigation are “exceptional circumstances warranting an accommodation to Congress,” according to a letter from Associate Deputy Attorney General Bradley Weinsheimer.

“Congress has articulated compelling legislative interests in the matters being investigated, and the information the Committees have requested from you bears directly on Congress’s interest in understanding these extraordinary events: namely, the question whether President Trump sought to cause the Department to use its law enforcement and litigation authorities to advance his personal interests with respect to the results of the 2020 presidential election,” Weinsheimer’s letter said.

Donald Ayer, a former deputy attorney general in the George H.W. Bush administration, said the decision represents “a piece of a larger effort making possible accountability for various misdeeds of the previous administration, including but not limited to the attempt to overturn the election and the conduct in instigating Jan. 6.”

Gurulé said Justice’s move to set aside the executive privilege protection removes a substantial legal obstacle.

“But the American people shouldn’t expect to see Trump officials to be sitting for testimony any time soon,” Gurulé said.

The House has clear legal authority to subpoena former Trump administration officials, who are now private citizens, and even its own members, according to legal experts.

“I don’t think there’s any question about their legal authority,” said Michael Stern, a former House senior counsel. “The practical matter is how do they enforce it.”

If potential witnesses defy their subpoenas, the House could ask the courts to enforce the subpoenas through civil lawsuits or lawmakers could refer the cases to the Justice Department for possible criminal prosecution for contempt.

Stern said people in the private sector sometimes resist subpoenas, but that puts them in a position facing potential criminal prosecution.

“Unless they have a strong privilege claim, they are taking a big risk,” Stern said.

McGahn case illustrated disputes

Despite the Justice Department decisions, potential witnesses could still fight their subpoenas on their own. The Supreme Court has upheld a doctrine of executive privilege, which says presidents can keep communications confidential so they can receive candid advice.

Don McGahn, the former White House counsel for Trump, fought a House subpoena in federal courts for two years before negotiating a compromise to testify behind closed doors in May and a transcript was released days later.

His case illustrated the kinds of arguments that witnesses might make in the Jan. 6 investigation.

The House Judiciary Committee sought McGahn’s testimony in May 2019 because he was a key figure in special counsel Robert Mueller’s investigation of Russian interference in the 2016 election. McGahn described several episodes of possible obstruction by Trump as he sought to remove Mueller or curb his probe.

But McGahn defied the subpoena. The head of the Justice Department’s Office of Legal Counsel, Steven Engel, told then-White House Counsel Pat Cipollone that McGahn and other advisers to the president cannot be compelled to testify under a theory they were protected by “absolute immunity.”

“The Department has long taken the position – across administrations of both political parties – that ‘the President and his immediate advisers are absolutely immune from testimonial compulsion by a Congressional committee,'” Cipollone wrote in May 2019.

Judiciary Chairman Jerry Nadler, D-N.Y., argued during Trump’s first impeachment trial in January 2020 that he waived claims to executive privilege by giving his side of contested conversations and that absolute immunity was a “ridiculous” assertion.

“He has claimed, instead, absolute immunity – a ridiculous doctrine that the president has absolute immunity from any questioning by the Congress or by anybody else. It is a claim rejected by every court that has ever considered it,” Nadler said.

Indeed, U.S. District Judge Ketanji Brown Jackson rejected the White House’s claims of absolute immunity in the McGahn case, saying the president “does not have the power” to prevent his aides from responding to congressional subpoenas.

“Today, this Court adds that this conclusion is inescapable precisely because compulsory appearance by dint of a subpoena is a legal construct, not a political one, and per the Constitution, no one is above the law,” Jackson wrote.

Swalwell case against Brooks reveals how testimony could occur

A lawsuit between two House members over responsibility for the insurrection could shed light on how the Justice Department and the courts will deal with the unprecedented attack on the Capitol.

Rep. Eric Swalwell, D-Calif., sued Rep. Mo Brooks, R-Ala.; Trump; the former president’s eldest son Donald Trump Jr.; and Trump’s personal attorney Rudy Giuliani, alleging they helped instigate the attack. Each of the defendants spoke at the Trump rally near the White House before the attack on the Capitol.

Brooks sought to have the case thrown out with the argument he was acting in his official capacity as a House member. The Constitution typically protects what lawmakers say under the speech-and-debate clause, so they can speak freely.

But the Justice Department filed a response in the case Tuesday that the protection doesn’t apply because Brooks was speaking in a personal capacity at a political rally rather than an official government function.

“The record indicates that Brooks’s appearance at the January 6 rally was campaign activity, and it is no part of the business of the United States to pick sides among candidates in federal elections,” Taheerah El-Amin, a Justice lawyer, said in the filing. “The conduct at issue here thus is not the kind a Member of Congress holds office to perform, or substantially within the authorized time and space limits, as required by governing law.”

Ayer said the same reasoning could eventually apply to Trump.

“The most important reason given by the government for that conclusion is that actions aimed at undermining the functioning of our government, including interference with the outcome of a free and fair election, are not within the scope of duty for any government employee,” Ayer said.