House Speaker Nancy Pelosi (D-CA) announced Monday that she will establish what she described as an “outside, independent 9/11-type Commission” to investigate last month’s deadly riot at the U.S. Capitol.

In her weekly letter to colleagues, Pelosi said the commission will “investigate and report on the facts and causes relating to the January 6, 2021, domestic terrorist attack upon the United States Capitol Complex … and relating to the interference with the peaceful transfer of power.”

Pelosi’s announcement comes two days after the U.S. Senate voted to acquit former President Donald Trump over his conduct leading up to the riot during which five people died, including a U.S. Capitol Police officer. The Senate voted 57-43 to acquit the former president, with seven Republican senators voting in favor of conviction.

High profile Senate Democrats, including Sen. Chris Coons (D-DE) have expressed support for a 9/11 commission to investigate the riot.

“There’s still more evidence that the American people need and deserve to hear and a 9/11 commission is a way to make sure that we secure the Capitol going forward,” Coons said. “And that we lay bare the record of just how responsible and how abjectly violating of his constitutional oath President Trump really was.”

McConnell told Republican senators shortly before the vote that he would vote to acquit Trump. In a blistering speech after the vote, the Kentucky Republican said the president was “practically and morally responsible for provoking the events of that day” but that the Senate’s hands were tied to do anything about it because Trump was out of office. The Senate, in an earlier vote, had deemed the trial constitutional.

“It was powerful to hear the 57 guilties and then it was puzzling to hear and see Mitch McConnell stand and say ‘not guilty’ and then, minutes later, stand again and say he was guilty of everything,” said Rep. Madeleine Dean, D-Pa. “History will remember that statement of speaking out of two sides of his mouth,” she said.

The Associated Press contributed to this report.