In a statement, Cheney, a staunch conservative, said Trump was responsible for the death and destruction that day.
“The President of the United States summoned this mob, assembled the mob, and lit the flame of this attack. Everything that followed was his doing. None of this would have happened without the President,” said Cheney. “The President could have immediately and forcefully intervened to stop the violence. He did not.”
“There has never been a greater betrayal by a President of the United States of his office and his oath to the Constitution,” she added. “I will vote to impeach the President.”
The House plans to vote on one article of impeachment Wednesday charging Trump with “incitement of insurrection,” as it races toward making him the first President in history to be impeached twice. Cheney has said that the vote should be driven by one’s conscience.
Unlike the other two top leaders in her conference — House Republican Leader Kevin McCarthy and House Republican Whip Steve Scalise — Cheney opposed Trump’s efforts to overturn the election, and voted to certify the results last week.
Arizona Republican Rep. Andy Biggs, the chair of the fiercely pro-Trump Freedom Caucus, said Cheney should resign from her leadership position as conference chair for coming out in support of impeaching Trump.
McCarthy’s staff asked for a call Tuesday with McCarthy to ask him to explain his actions, “and he couldn’t be bothered to join the call,” according to a person close to the matter. Senior advisers to McCarthy, who are paying careful attention to his potential 2022 run for Speaker if the GOP wins back the House, released details of a recent call with House Republicans in which he insisted that Trump supporters, rather than Antifa, stormed the Capitol.
But that has done little to quell their concern that McCarthy has been tarnished by his defense of the President. On the eve of the impeachment vote, senior advisers are trying to keep some staff from quitting.
A McCarthy spokesman responded, “This is completely inaccurate.” The spokesman said that that McCarthy’s office held a staff call while the House GOP leader “was on the road” and he “was never intended” to participate on the call.
“It’s been a tough week but today’s call reaffirmed the bonds and commitment we have to our important work,” said the spokesman.
The House GOP leader ignored questions Tuesday evening on whether Trump was responsible for the riot, walking into the chamber in silence.
Cheney, the daughter of former Vice President Dick Cheney, has broken with Trump in the past, including on various foreign policy issues and by supporting Dr. Anthony Fauci, the nation’s leading infectious disease expert, during the coronavirus pandemic.
When asked about Cheney’s decision to impeach the President, House Speaker Nancy Pelosi responded, “Good for her to be honoring the oath of office.”
This story has been updated with additional developments Tuesday.
CNN’s Manu Raju, Phil Mattingly and Annie Grayer contributed to this report.