WASHINGTON (AP) — President Donald Trump on Monday pardoned, commuted the prison sentences or vowed to dismiss the cases of all of the 1,500-plus people charged with crimes in the Jan. 6, 2021, U.S. Capitol riot, including people convicted of assaulting police officers, using his clemency powers on his first day back in office to undo the massive prosecution of the unprecedented assault on the seat of American democracy.

Trump’s action, just hours after his return to the White House, paves the way for the release from prison of people found guilty of violent attacks on police, as well as leaders of far-right extremist groups convicted of failed plots to keep the Republicans in power after he lost the 2020 election to former President Joe Biden.

The pardons are a culmination of Trump’s yearslong campaign to rewrite the history of the Jan. 6 attack that left more than 100 police officers injured as the angry mob of Trump supporters — some armed with poles, bats and bear spray — overwhelmed law enforcement, shattered windows and sent lawmakers and aides running into hiding. While pardons were expected, the speed and the scope of the clemency amounted to a stunning dismantling of the Justice Department’s effort to hold participants accountable over what has been described as one of the darkest days in the country’s history.

Former Proud Boys leader Enrique Tarrio, who was sentenced to 22 years in prison after his conviction of seditious conspiracy, was being processed for release from his cell in Louisiana following Trump’s executive action, his lawyer told ABC News Monday evening.

Craig Sicknick, whose brother Capitol Police officer Brian Sicknick died the day after being attacked by rioters, told ABC News’ Rachel Scott that Trump’s pardons were a “betrayal of decency.”

“The man doesn’t understand pain or suffering of others. He can’t comprehend anyone else’s feelings,” Sicknick said. “We now have no rule of law.”

U.S. Capitol Police Officer Brian Sicknick, who engaged with pro-Trump rioters during the Jan. 6 insurrection, was sprayed with a chemical substance outside the Capitol at around 2:20 p.m. ET on Jan. 6, the report said.

At approximately 10 p.m., 42-year-old Sicknick collapsed at the Capitol and was transported to a local hospital. He died nearly 24 hours later after suffering two strokes brought on by the rioter’s attacks of the Capitol.

Sicknick has been counted as one of five people who died as a result of the insurrection attempt at the U.S. Capitol during which extremists — egged on by then-President Donald Trump and his acolytes in Congress — stormed the complex in an attempt to halt the certification of President Biden’s White House victory.