Cassidy Hutchinson said Trump was warned about potential violence, crimes.
The House select committee investigating the U.S. Capitol attack heard stunning testimony on Tuesday from Cassidy Hutchinson, a former top aide to then-White House chief of staff Mark Meadows.
She told the committee and an international TV audience that then-President Donald Trump was warned about potential violence and crimes, that he wanted supporters with weapons let into his Jan. 6 rally, and that she was told he then demanded his security detail take him to the Capitol, going so far as to grab the wheel of the presidential SUV.
This was the sixth hearing this month investigating what the committee says was the conspiracy by Trump and his allies to overturn the election.
With the nature of the hearing coming up with little notice, signaling urgency for the committee, reporters and cameras swarmed the witness table inside the Cannon Office Building ahead of Cassidy Hutchinson taking her seat.
Hutchinson entered the hearing room at 1 p.m. with members of the Jan. 6 committee.
ABC News Chief Washington Correspondent Jon Karl said sources have told him the hearing will be "Big —and disturbing."
Former White House deputy press secretary Sarah Matthews showed support for Cassidy Hutchinson ahead of her scheduled testimony.
"Just want to say how much admiration I have for the tremendous bravery Cassidy Hutchinson is displaying," Matthews wrote on Twitter. "Even in the face of harassment and threats, she is choosing to put her country first and tell the truth."
"This is what real courage, integrity, and patriotism looks like," Matthews added.
Matthews resigned from her position in the Trump administration on Jan. 6 , stating she was "deeply disturbed" by what took place that day.
Cassidy Hutchinson hired a new attorney, Jody Hunt, earlier this month to represent her as the public Jan. 6 hearings began. Her agreement to testify publicly comes after months of negotiations between the committee and her counsel, sources told ABC News.
At the start of the Trump administration, Hunt served as chief of staff to then-Attorney General Jeff Sessions. He later became the head of the Department of Justice's Civil Division.
The committee's expected witness, Cassidy Hutchinson, is a former top adviser to Trump's White House chief of staff Mark Meadows.
A 2019 political science graduate of Virginia's Christopher Newport University, Hutchinson was as an intern to House GOP Whip Steve Scalise, R-La., and Sen. Ted Cruz, R-Texas, in college before serving as a White House intern in 2018. After graduating, she joined the Trump White House Office of Legislative Affairs, before joining Meadows as an executive assistant, and later a special assistant to the president.
"I have set a personal goal to pursue a path of civic significance," she told her alma mater in a 2018 interview after her White House internship.
Having already sat four separate times for closed-door depositions with the committee, Hutchinson has been featured in clips publicly displayed by the committee, including some in which she discussed members of Congress asking the White House for pardons.
