In its opening act, the House select committee investigating the January 6 attack on the Capitol holds its first high-profile hearing Tuesday with testimony from four officers who will give firsthand accounts of the horrors they witnessed and endured as rioters stormed the building.

The officers are expected to recount the harrowing attacks they faced on January 6, including being beaten with a flagpole, getting crushed in a doorway, being the target of racial slurs and facing rioters who tased them. The committee also is expected to show never-before-seen videos depicting the violence from that day, just as House impeachment managers did during the impeachment trial of former President Donald Trump.

The emotional testimony kicks off the committee’s investigation into the circumstances surrounding the January 6 attack as Democratic leaders look to set the tone for a panel that congressional Republicans have dismissed as a political sideshow created merely to discredit the legacy of the former President.

The goal Tuesday, according to select committee member Democratic Rep. Adam Schiff of California, is to portray what it was like “to be on the front lines for the brave police officers” and to push back on efforts to whitewash the events of that day.

“I’m hoping that the hearing will give the American people an even more vivid sense of what went on that day, the horror of that day, how these brave police officers saved so many lives,” Schiff told CNN.

Investigative report from Joshua Kaplan and Joaquin Sapien at ProPublica: New Details Suggest Senior Trump Aides Knew Jan. 6 Rally Could Get Chaotic.

On Dec. 19, President Donald Trump blasted out a tweet to his 88 million followers, inviting supporters to Washington for a “wild” protest.

Earlier that week, one of his senior advisers had released a 36-page report alleging significant evidence of election fraud that could reverse Joe Biden’s victory. “A great report,” Trump wrote. “Statistically impossible to have lost the 2020 Election. Big protest in D.C. on January 6th. Be there, will be wild!”

The tweet worked like a starter’s pistol, with two pro-Trump factions competing to take control of the “big protest.”

On one side stood Women for America First, led by Amy Kremer, a Republican operative who helped found the tea party movement. The group initially wanted to hold a kind of extended oral argument, with multiple speakers making their case for how the election had been stolen.

On the other was Stop the Steal, a new, more radical group that had recruited avowed racists to swell its ranks and wanted the President to share the podium with Alex Jones, the radio host banned from the world’s major social media platforms for hate speech, misinformation and glorifying violence. Stop the Steal organizers say their plan was to march on the Capitol and demand that lawmakers give Trump a second term.

ProPublica has obtained new details about the Trump White House’s knowledge of the gathering storm, after interviewing more than 50 people involved in the events of Jan. 6 and reviewing months of private correspondence. Taken together, these accounts suggest that senior Trump aides had been warned the Jan. 6 events could turn chaotic, with tens of thousands of people potentially overwhelming ill-prepared law enforcement officials.

Rather than trying to halt the march, Trump and his allies accommodated its leaders, according to text messages and interviews with Republican operatives and officials.

Katrina Pierson, a former Trump campaign official assigned by the White House to take charge of the rally planning, helped arrange a deal where those organizers deemed too extreme to speak at the Ellipse could do so on the night of Jan. 5. That event ended up including incendiary speeches from Jones and Ali Alexander, the leader of Stop the Steal, who fired up his followers with a chant of “Victory or death!”