What happened on January 6, 2021?
On January 6, 2021, following the defeat of U.S. President Donald Trump in the 2020 presidential election, a mob of his supporters attacked the United States Capitol Building in Washington, D.C. The mob sought to keep Trump in power by preventing a joint session of Congress from counting the electoral college votes to formalize the victory of President-elect Joe Biden. According to the House select committee investigating the incident, the attack was the culmination of a seven-part plan by Trump to overturn the election. Five people died either shortly before, during, or following the event: one was shot by Capitol Police, another died of a drug overdose, and three died of natural causes. Many people were injured, including 138 police officers. Four officers who responded to the attack died by suicide within seven months. As of July 7, 2022, monetary damages caused by attackers exceed $2.7 million.

Called to action by Trump, thousands of his supporters gathered in Washington, D.C., on January 5 and 6 to support his false claim that the 2020 election had been "stolen by emboldened radical-left Democrats" and to demand that Vice President Mike Pence and the Congress reject Biden's victory. Starting at noon on January 6, at a "Save America" rally on the Ellipse, Trump repeated false claims of election irregularities and said "If you don't fight like hell, you're not going to have a country anymore." In the same speech, he said "I know that everyone here will soon be marching over to the Capitol building to peacefully and patriotically make your voices heard." During and after his speech, thousands of attendees, some armed, walked to the Capitol, and hundreds breached police perimeters as Congress was beginning the electoral vote count.

More than 2,000 rioters entered the building, many of whom occupied, vandalized, and looted; assaulted Capitol Police officers and reporters; and attempted to locate lawmakers to capture and harm. A gallows was erected west of the Capitol, and some rioters chanted "Hang Mike Pence" after he rejected false claims by Trump and others that the vice president could overturn the election results. Some vandalized and looted the offices of House Speaker Nancy Pelosi (D‑CA) and other members of Congress. With building security breached, Capitol Police evacuated and locked down both chambers of Congress and several buildings in the Capitol Complex. Rioters occupied the empty Senate chamber while federal law enforcement officers defended the evacuated House floor. Pipe bombs were found at each of the Democratic National Committee and Republican National Committee headquarters, and Molotov cocktails were discovered in a vehicle near the Capitol.

Trump resisted sending the National Guard to quell the mob. Later that afternoon, in a Twitter video, he reasserted that the election was "fraudulent", but told his supporters to "go home in peace". The Capitol was clear of rioters by mid-evening, and the counting of the electoral votes resumed and was completed in the early morning hours of January 7. Pence declared President-elect Biden and Vice President-elect Kamala Harris victorious. Pressured by his cabinet, the threat of removal, and many resignations, Trump later committed to an orderly transition of power in a televised statement.

A week after the riot, the House of Representatives impeached Trump for incitement of insurrection, making him the only U.S. president to have been impeached twice. In February, after Trump had left office, the Senate voted 57–43 in favor of conviction; because this fell short of a two-thirds majority, requiring 67 votes, he was acquitted for a second time. The House passed a bill to create a bipartisan independent commission to investigate the attack, modeled after the 9/11 Commission, but it was blocked by Republicans in the Senate, so the House approved a select committee with seven Democrats and two Republicans to investigate instead. The committee held nine televised public hearings on the attack  in 2022, and later voted to subpoena Trump. By March 2022, the Justice Department's investigations had expanded to include the activities of others leading up to the attack. Ultimately, the Committee recommended Trump to DOJ to be prosecuted for obstructing an official proceeding, incitement, conspiracy to defraud the United States, and making false statements.

More than 30 members of anti-government groups, including the Oath Keepers, Proud Boys, and Three Percenters, were charged with conspiracy for allegedly planning their attacks on the Capitol; ten Oath Keepers and five Proud Boys were charged with seditious conspiracy, and one Oath Keeper pleaded guilty. Oath Keeper leader Stewart Rhodes would later be convicted of seditious conspiracy. As of January 2022, at least 57 people with roles in the day's events were running for public office. Although most people charged with crimes relating to the attack had no known affiliation with far-right or extremist groups, a significant number were linked to extremist groups or conspiratorial movements. By January 2023, at least 476 individuals charged had pleaded guilty.