The House committee investigating the Jan. 6 attack on the Capitol said it is preparing to hold Mark Meadows in criminal contempt for not complying with its subpoena as it laid out evidence Wednesday showing the former White House chief of staff’s support for efforts to overturn the 2020 election.

Committee Chairman Bennie G. Thompson (D-Miss.), in a letter to Meadows attorney George Terwilliger III, criticized Meadows’s decision to no longer cooperate with the panel. The onetime North Carolina congressman reversed course this week, arguing the panel was pressuring him to discuss issues that former president Donald Trump said are protected by executive privilege.

“There is no legitimate legal basis for Mr. Meadows to refuse to cooperate with the Select Committee and answer questions about the documents he produced, the personal devices and accounts he used, the events he wrote about in his newly released book, and, among other things, his other public statements,” Thompson wrote in a letter sent to Terwilliger on Tuesday night and released publicly Wednesday.

The House select committee investigating the attempted insurrection at the Capitol on Jan. 6 faces an uphill battle with former Trump administration officials. (Blair Guild/The Washington Post)

In his letter, Thompson details some of the emails and text messages Meadows had already handed over to the committee, providing one of the first glimpses of internal communications the panel has obtained that illuminate the actions of Trump and his allies. The new materials show Meadows was involved in early discussions to appoint an alternate slate of electors to replace those prepared to certify Joe Biden the victor in certain states, including an email sent days after the election that described a “a direct and collateral” attack on the results.

The letter highlights the committee’s focus not just on the specific events of Jan. 6 but the actions undertaken by Trump and his associates leading up to that day, when a mob of Trump supporters stormed the Capitol while echoing the false claims he made about a stolen election.

The panel appears to be focusing heavily on an effort by Trump’s allies to develop a plan in which Vice President Mike Pence would have halted Congress’s certification of the election on Jan. 6 to allow Republican state legislators to investigate the unfounded fraud claims. Trump privately and publicly pressured Pence to embrace the plan, but the vice president would not, arguing he did not have the power to do so under the Constitution.

The information released by the panel Wednesday suggests that Meadows was deeply involved in the effort to overturn the election results.

Along with the discussion to appoint an alternate slate of electors, Thompson outlined in his letter other documents Meadows has already provided to the committee, including a Jan. 5 email “regarding a 38-page PowerPoint briefing titled ‘Election Fraud, Foreign Interference & Options for 6 JAN’ that was to be provided ‘on the hill’ ” and a Jan. 5 “email about having the National Guard on standby.”

The text messages produced by Meadows also include a Nov. 6, 2020, correspondence “with a Member of Congress apparently about appointing alternate electors in certain states as part of a plan that the Member acknowledged would be ‘highly controversial’ and ­to which Mr. Meadows apparently said, ‘I love it.’ ”

Meadows also turned over messages about “the need for the former President to issue a public statement that could have stopped the January 6th attack on the Capitol,” according to Thompson, along with an early-January 2021 text message exchange between Meadows and an unnamed organizer of the Jan. 6 rally on the Ellipse that proceeded the attack on the Capitol.

“All of those documents raise issues about which the Select Committee would like to question Mr. Meadows and about which you appear to agree are not subject to a claim of privilege,” Thompson wrote to Terwilliger.

Thompson noted that information Meadows provided came from his personal cellphone and email address instead of his government accounts, raising questions about whether he has turned over that information to the National Archives as required.

Meadows was among many Republicans who heavily criticized Hillary Clinton during the 2016 presidential campaign for her use of a private email server while she was secretary of state.

Meadows and Terwilliger did not provide a comment in response to Thompson’s letter. But on Wednesday, Meadows filed a lawsuit against Speaker Nancy Pelosi (D-Calif.) and all nine members of the House Jan. 6 committee, according to a court filing provided by Terwilliger. The 43-page complaint, filed in D.C.’s U.S. District Court, asks that the court “invalidate and prohibit the enforcement of two overly broad and unduly burdensome subpoenas.”

The committee has in recent weeks ramped up efforts to force recalcitrant Trump administration officials to cooperate with its inquiry.

Last month, the Justice Department filed contempt-of-Congress charges against former Trump strategist Stephen K. Bannon, who refused to meet with the committee or provide any documents in response to a congressional subpoena, after the House approved a resolution finding him in criminal contempt of Congress.

Earlier this month, the panel approved a resolution finding former Justice Department official Jeffrey Clark in criminal contempt of Congress, but the full House has yet to act, after the committee decided to give him another opportunity to be deposed later this month. Clark’s attorney has indicated he may invoke his Fifth Amendment right not to answer a broad swath of questions.

The criminal contempt charge is a misdemeanor, punishable by up to a year in jail and a fine of up to $1,000.

Meadows’s refusal to sit for an interview with the panel, as previously agreed, marks a reversal following Trump’s angry outbursts against Meadows about his new memoir, “The Chief’s Chief,” which was published Tuesday after its contents were reported by several news organizations last week.

Trump has disputed some of Meadows’s revelations — particularly about Trump’s health and his first positive coronavirus test before a negative coronavirus test ahead of a presidential debate.

Former officials said Meadows was often duplicitous around the election and gave in to some of Trump’s worst instincts by passing along conspiracy claims to the president and to the Justice Department.

Meadows encouraged Trump to pressure officials, orchestrating calls with state officials and giving the president false hope that he could win, according to people familiar with the situation who spoke on the condition of anonymity to describe private conversations.

Meadows, who could be held in contempt by the committee as soon as next week, was around the president throughout Jan. 6, and his testimony could offer a firsthand account of why Trump did not issue a statement for several hours after the start of the attack.

Thompson told reporters Tuesday that the committee members will “do all they can” to get his testimony, saying Meadows’s role as chief of staff “during this time period is significant.”

Since Trump left office, Meadows has frequently kept in touch with the former president and even held events for his political group at Trump’s club in Palm Beach, Fla.

In his book, Meadows said Trump was “mortified” at what happened on Jan. 6. Officials around Trump have disputed that, saying he was still looking to block the election results as rioters ransacked the Capitol.

Despite Meadows’s reluctance to cooperate with the committee, he wrote about his time at the White House extensively in his new book, raising additional legal questions about his ability to cite executive privilege as a reason not to cooperate.

“It’s always difficult to maintain any claim of privilege after you have already divulged information publicly throughout the course of the investigative body that falls within the privilege you are asserting,” said Robert Kelner, who leads the congressional investigations practice at the firm of Covington and Burling. “This is what lawyers refer to as waiving the privilege, and from public reports there’s serious questions here about whether he’s waived it through his book and materials he’s provided to Congress.”

Kelner and other lawyers following the case have also noted that President Biden has not asserted a claim of executive privilege over any of the information being sought by the committee and that his position may have more legal standing as the sitting president than Trump’s assertions as a private citizen.

Meadows in his book wrote that Trump told him he had been “speaking metaphorically” when he told the audience at the Stop the Steal rally to “walk down to the Capitol” before the Capitol breach.

“The real question — the one that should be investigated by Congress — is why, despite several offers from the White House and [the Defense Department] to send 10,000 National Guard into our nation’s capital before the January 6 rally, Mayor Muriel Bowser refused to accept their help,” Meadows claims in the book.

The Washington Post has previously reported that Pentagon leaders had acute fears about violence on Jan. 6 and feared that Trump could misuse the National Guard to remain in power.

Then-acting defense secretary Christopher C. Miller said that while he did not believe Trump would misuse the military, he worried far-right extremists could bait soldiers into “a Boston Massacre-type situation.”

Despite assessments of the risk of possible violence, those fears ultimately contributed to the hours-long delay in getting the Guard to the Capitol.

Trump has attacked the committee over its investigation and continues to spread false claims about the election.

“They cheat like hell in the elections,” he said of Democrats during an interview with conservative media figure Hugh Hewitt on Wednesday. “What happened should never be allowed, what happened, and we’re not forgetting it.”