Transportation Secretary Elaine Chao and Education Secretary Betsy DeVos announced their resignations Thursday, citing the pro-Trump rioters who stormed the Capitol on Wednesday.
"Yesterday, our country experienced a traumatic and entirely avoidable event as supporters of the president stormed the Capitol building following a rally he addressed," Chao said in a statement she posted on Twitter. "As I'm sure is the case with many of you, it has deeply troubled me in a way that I simply cannot set aside."
Chao said her last day would be Monday, and she suggested that she would use some of her final days to help President-elect Joe Biden's nominee for her job, Pete Buttigieg, "with taking on the responsibility of running this wonderful department."
She was the first Cabinet member to resign after Wednesday's riot, which was sparked by President Donald Trump's urging of thousands of his supporters to go to the Capitol to make their "voices heard" against lawmakers who were unsupportive of his call for objections during the counting of electoral votes in the presidential election.
Chao's husband, Senate Majority Leader Mitch McConnell of Kentucky, was the most prominent Republican to push back against Trump's plan.
DeVos, who has had a rocky tenure as education secretary, said late Thursday that her last day would be Friday. She said in her letter, obtained by NBC News, that the violent clash and Trump's rhetoric factored into her decision.
"We should be highlighting and celebrating your administration's many accomplishments on behalf of the American people," she said. "Instead, we are left to clean up the mess caused by violent protesters overrunning the U.S. Capitol in an attempt to undermine the people's business. That behavior was unconscionable for our country."
She added: "There is no mistaking the impact your rhetoric had on the situation, and it is the inflection point for me. Impressionable children are watching all of this, and they are learning from us."
Also announcing his resignation Thursday was Trump's special envoy to Northern Ireland, Mick Mulvaney, his former acting chief of staff.
Mulvaney said in an interview with CNBC that he called Secretary of State Mike Pompeo on Wednesday night "to let him know I would be resigning from that."
"I just can't do it. I can't stay," Mulvaney said. "The president of the United States went onstage and said go march down the street and invade the Capitol, and they did."
Mulvaney, a key figure in the Trump impeachment proceedings who defied a congressional subpoena to testify about what he knew, told CNBC that when he was acting chief of staff, "the president never asked us to do anything unethical or certainly illegal."
"Clearly, he is not the same as he was eight months ago, and certainly the people advising him are not the same as they were eight months ago, and that leads to a dangerous sort of combination, as you saw yesterday," Mulvaney said.
He acknowledged that his resignation is "a nothing thing."
"It doesn't affect the outcome, it doesn't affect the transition, but it's what I've got, and it's a position I really enjoy doing, but you can't do it," he said.
Mulvaney said he has spoken with friends in the administration and expects others to leave in the next day or two.
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"Those who choose to stay, and I have talked with a couple of them, are choosing to stay because they're concerned the president might put someone in to replace them that could make things even worse," Mulvaney said.
Sen. Joe Manchin, D-W.Va., said it could be better for the country if some officials didn't resign.
"I urge the good men and women honorably serving at all levels of the federal government to please stay at their post for the protection of our democracy," Manchin said. "The actions of a rogue president will not and should not reflect on you. Instead, your patriotism and commitment to the greater good of our country will be reaffirmed."
Deputy national security adviser Matthew Pottinger also resigned, his boss, Robert O'Brien, announced on Twitter.
"Asking Matt Pottinger to serve as my deputy was my first act as NSA and it turned out to be one of my best decisions. As he heads West to rejoin his family in beautiful Utah, Matt does so with my appreciation for a job well done and with my enduring friendship," O'Brien wrote in a pair of tweets.
O'Brien said Pottinger's work had led "to a great awakening in our country and around the world to the danger posed by the Chinese Communist Party."
The Justice Department announced the resignation of Assistant Attorney General Eric Dreiband, who had been the head of the Civil Rights Division. Dreiband said the job had been "an honor of a lifetime."
Dreiband made headlines last year for pushing back against coronavirus restrictions in numerous states and localities.
"Simply put, there is no pandemic exception to the U.S. Constitution and its Bill of Rights," he wrote in a letter to California Gov. Gavin Newsom last year.
Tyler Goodspeed, the acting chair of the Council of Economic Advisers, also resigned, the agency's chief of staff, Rachael Slobodien, confirmed. Goodspeed told The New York Times that "the events of yesterday made my position no longer tenable."
John Costello, the deputy assistant secretary of commerce for intelligence and security, tweeted that he'd resigned, as well. He called the riots an "unprecedented attack on the very core of our democracy — incited by a sitting president."
On Wednesday, Melania Trump's chief of staff, Stephanie Grisham, a former White House press secretary, left her post, as did deputy White House press secretary Sarah Matthews. White House Social Secretary Rickie Niceta stepped down, as well, a source familiar with the matter said.
On Thursday, Jerome Marcus, a lawyer who worked on behalf of the Trump campaign in a lawsuit involving the election in Pennsylvania, asked to withdraw as an attorney in the case.
In a letter to the judge, Marcus wrote that "the client [Trump] has used the lawyer's services to perpetrate a crime and the client insists upon taking action that the lawyer considers repugnant and with which the lawyer has a fundamental disagreement."
The letter didn't elaborate on the allegations. The underlying case centered on a Trump campaign complaint that poll watchers weren't allowed to view the counting of votes in Philadelphia. At an emergency hearing in November, Marcus acknowledged to the judge that there had been a "nonzero number" of poll watchers in the room. "I'm sorry, then what's your problem?" the judge responded.
The judge ultimately denied the campaign's bid to stop the vote count and worked out a compromise between elections officials and the campaign about how many observers were allowed inside.
Mulvaney became Trump's acting chief of staff in late 2018 after the president announced that John Kelly was resigning. Trump replaced Mulvaney in March, appointing Rep. Mark Meadows, R-N.C., in his place. Mulvaney has also previously been a House member from South Carolina and director of Trump's Office of Management and Budget.
"I can't stay here, not after yesterday," he said in the interview Thursday. "You can't look at that yesterday and think I want to be a part of that."