Since his resounding defeat in the presidential election in November, Donald Trump has done everything but concede to the democratic will of the American people. He unleashed an avalanche of lies and baseless claims of fraud — conspiracy theories that filled his supporters with a delusional belief that the election had been stolen from him. He filed a bevy of absurd lawsuits. He attempted to cajole and intimidate officials at all levels of government into subverting the election and keeping him in office. And then, running out of recourse, legitimate and illegitimate, he incited an insurrection against the government and the Constitution that he swore to uphold.

The attempted coup at the United States Capitol last Wednesday, which took place as lawmakers inside counted the electoral votes that would formalize Joe Biden’s overwhelming election by the American people, marks one of the lowest points in our country’s 245-year experiment in democracy.

From Andrew Jackson to Richard Nixon, we have seen presidents abuse their power, but we had never witnessed an American president incite a violent mob on the citadel of our democracy in a desperate attempt to cling to power.

We cannot let this go unanswered. With each day, Mr. Trump grows more and more desperate. We should not allow him to menace the security of our country for a second longer.

Once the House opens for legislative business, my co-authors — Representatives Ted Lieu and Jamie Raskin — and I will introduce an article of impeachment to remove Mr. Trump from office for incitement of insurrection.

As lawmakers who have impeached this president once before, we do not take this responsibility lightly. In fact, it was not our first choice of action. In the midst of last Wednesday’s siege, we were among those that asked Vice President Mike Pence to convene the Cabinet to invoke the 25th Amendment to quickly remove Mr. Trump from office. We have called on the president to resign.

Days have passed, and it is clear that neither of those possibilities will be realized. So it is Congress’s responsibility to act.

The American people witnessed Mr. Trump’s actions for themselves. We all saw his speech on Jan. 6. We watched his fanatics storm the Capitol at his request. Five people died, including a U.S. Capitol Police officer and four of the president’s supporters. We fear what Mr. Trump may do with his remaining time in office.

That is why we believe the article of impeachment should be voted on as soon as possible. It is true that even after we act, Senator Mitch McConnell may, as he did one year ago, try to prevent a conviction in the U.S. Senate. It is also true that a trial might extend into the first days of the Biden administration.

Neither of those possibilities should deter us in our work. Some argue that another impeachment trial would further divide our country and further inflame Trump supporters. But the truth is that we do not have a choice. This impeachment charge is meant to defend the integrity of the republic. Both Democratic and Republican members of Congress must attend to the duties of their oath. Failing to act would set an irresponsibly dangerous precedent for future presidents who are about to leave office.

Further, there can be no healing of the divisions in our country without justice for the man most responsible for this horrific insurrection. The president must be held accountable. That can happen only by impeaching him for a second time and convicting him in the Senate. A conviction that would allow Congress to prohibit him from ever serving in federal office again.

What happened last Wednesday was an abomination. There is no question about that. There is also no question that Mr. Trump becomes more of a threat to public safety by the moment.

The only question now is what Congress will do about it.

David N. Cicilline (@davidcicilline) is a member of the Democratic Party and House Judiciary Committee who has represented Rhode Island’s First Congressional District since 2011.

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