WASHINGTON – The U.S. Senate voted Tuesday to proceed with the impeachment trial of former President Donald Trump on a charge that he incited insurrection at the U.S. Capitol last month by urging hundreds of his supporters to confront lawmakers as they met to certify that Democrat Joe Biden had defeated him in last November’s election.

The 56-44 vote to start hearing evidence in the case at mid-day Wednesday came after four hours of impassioned arguments about the constitutionality of holding the trial while Trump is no longer in office.

Democratic lawmakers from the House of Representatives prosecuting the case against Trump said the former U.S. leader must be held to account for his actions in his final weeks in office.

Trump’s two lawyers contended that the country’s Founding Fathers, in writing the Constitution, only intended for impeachment to be used as a tool to remove a president from office, an impossibility in Trump’s case since his four-year term ended January 20 as Biden was inaugurated.

Acting Sergeant at Arms Timothy Blodgett, right, leads Rep. Jamie Raskin, D-Md., second from right, the lead Democratic House impeachment manager, and other impeachment managers, through the Rotunda to the Senate, Feb. 9, 2021.

As Trump’s impeachment trial opened, Congressman Jamie Raskin of Maryland, one of the House impeachment managers prosecuting Trump, said that if Trump is not held accountable, it “would create a brand-new January exception” where future presidents would not face consequences for any wrongdoing during their final month in office.

Video of January 6 violence

The Democrats showed the Senate a dramatic video of the chaos that unfolded in the Capitol on January 6, with rampaging protesters storming past authorities and lawmakers scrambling to avoid the violence, shortly after they had started to certify that Biden had defeated Trump in last November’s election.

Raskin recalled that his chief of staff, daughter and son-in-law were forced to barricade themselves in House Majority Leader Steny Hoyer’s office and hide under a desk while rioters banged on the office door, “placing what they thought were their final texts and whispered phone calls to say their goodbyes. They thought they were gonna die.”

FILE – Supporters of then-President Donald Trump riot in front of the U.S. Capitol in Washington, Jan. 6, 2021.

Trump, who urged hundreds of supporters to confront lawmakers at the Capitol in a last-ditch effort to upend the election results, was impeached a week later and left office January 20 as Biden was inaugurated as the country’s 46th president.

Raskin said that every day a president is in office “he’s prohibited from committing high crimes and misdemeanors” – the standard for conviction on impeachment charges – and cannot avoid responsibility for the deadly mayhem at the Capitol because he now is out of office.

But Trump’s lawyers sharply disputed the legality of the Senate holding an impeachment trial on the allegation by the House of Representatives that Trump engaged in “incitement of insurrection” by urging his supporters to march on the Capitol and “fight like hell.”

Trump lawyer Bruce Castor Jr. said, “The idea of a January exception [for presidential responsibility for his actions] is nonsense.” He said that if Trump committed any offenses, “arrest him,” now that he is a private citizen and no longer immune from prosecution.

Castor quoted the Constitution saying that conviction on impeachment charges “shall not extend further than removal from office,” an impossibility since Trump’s four-year term in the White House has already ended.

“The object of the Constitution has already been achieved,” Castor said. “He was removed by the voters.”

Trump’s other lawyer, David Schoen, accused Democrats of pursuing the impeachment case against him “to eliminate Donald Trump from the American political scene.” He said “pure, raw, misguided partisanship” was at the heart of the Democrats’ case against the former president.

In this image from video, the vote total on the question of the constitutionality of the impeachment trial against former President Donald Trump is displayed in the Senate at the U.S. Capitol in Washington, Feb. 9, 2021.

Tuesday’s vote to proceed was expected.

Last month, Senator Rand Paul of Kentucky, a staunch Trump supporter, attempted to block the trial on the same constitutional grounds, but five Republicans joined all 50 Democrats in voting 55-45 to proceed with the trial.

In the new vote Tuesday, another Republican, Senator Bill Cassidy of Louisiana, also voted to go ahead with the trial.

Senate vote

However, it will take a two-thirds majority for conviction, meaning at least 11 more Republican senators would have to reverse their votes for the prosecution to prevail. The 100-seat Senate is currently evenly divided 50-50 between Republicans and Democrats.

Paul says there is a “zero chance of conviction.” If Trump is convicted, the Senate, on a simple majority vote, could bar him from ever holding federal office again.

In 1876, the Senate conducted an impeachment trial of a Cabinet secretary during the Grant administration who resigned moments before he was impeached. Trump was impeached by the House while still in office.

The protest on January 6 turned into mayhem, as about 800 Trump supporters rampaged past authorities into the Capitol, smashed doors and windows, ransacked some congressional offices and scuffled with police. Five people were killed, including a Capitol Police officer whose death is being investigated as a homicide, and a rioter shot by an officer.

FILE – Pro-Trump protesters storm the U.S. Capitol to contest the certification of the 2020 U.S. presidential election results by Congress, at the U.S. Capitol in Washington, Jan. 6, 2021.

The 100 senators deciding the impeachment case against the single-term president are in a unique position: Many of them were witnesses themselves to the chaos as they fled the Senate chamber.

Trump, the only U.S. president to be twice impeached, was acquitted a year ago when he was accused of soliciting the president of Ukraine to dig up dirt against Biden ahead of last November’s election.

A week after the storming of the Capitol, the House voted 232-197, with 10 Republicans joining all 222 Democrats, to accuse Trump of “incitement of insurrection.” Then, on January 20, Biden was inaugurated and Trump, no longer in power, flew for the last time on Air Force One to his Atlantic coastline mansion in Florida, where he has stayed since.

Trump has declined a request from Democrats to testify in his defense at his impeachment trial and is not expected to attend. The trial could last a week or longer.

The nine Democratic House impeachment managers bringing the case against Trump – several of them former prosecutors – say that Trump, by urging his supporters to contest his election defeat at the Capitol, was “singularly responsible” for the riot that ensued.

Trump urged supporters to come to Washington on January 6, saying it would be “wild.” At a rally near the White House shortly before his supporters walked 16 blocks to the Capitol, Trump continued his weekslong barrage of unfounded claims that election fraud had cost him another four-year term.

Speaking for more than an hour, Trump told his supporters “to peacefully and patriotically make your voices heard” by marching to the Capitol.

FILE – Then-President Donald Trump speaks a rally contesting the certification of the 2020 U.S. presidential election results by Congress, in Washington, Jan. 6, 2021.

But he also exhorted them, saying, “Our country has had enough. We will not take it anymore and that’s what this is all about. To use a favorite term that all of you people really came up with, we will stop the steal.”

“And we fight,” he said. “We fight like hell and if you don’t fight like hell, you’re not going to have a country anymore.”

Ahead of the trial, the House impeachment managers said in a legal brief, “President Trump’s responsibility for the events of January 6 is unmistakable” and that the former president’s “conduct must be declared unacceptable in the clearest and most unequivocal terms,” even though he is no longer in office.

Assuming the Senate votes to go ahead with the trial after debating its constitutionality, House managers will begin to present their case on Wednesday, likely showing some of the hours of videos recording the mayhem, much as they did Tuesday.

The president’s lawyers will then respond with his defense. According to an agreement announced Monday by congressional leaders, each side will have 16 hours over two days to present their arguments.

Later in the week, the Senate will have an opportunity to debate whether to call witnesses. The House managers could call some of the rioters to testify they were responding to Trump’s call for them to confront lawmakers certifying Biden’s victory.

Trump’s lawyers have mounted a vigorous defense and contend that the former president bears no responsibility for what occurred last month.

In a brief filed Monday, they said the case against him amounts to “political theater” brought by anti-Trump Democrats. Trump’s lawyers suggested that he was simply exercising his constitutionally guaranteed right of free speech when he disputed the election results and argued that he explicitly encouraged his supporters to engage in a peaceful protest.

“Instead, this was only ever a selfish attempt by Democratic leadership in the House to prey upon the feelings of horror and confusion that fell upon all Americans across the entire political spectrum upon seeing the destruction at the Capitol on Jan. 6 by a few hundred people,” the lawyers wrote.

“Instead of acting to heal the nation, or at the very least focusing on prosecuting the lawbreakers who stormed the Capitol, the Speaker of the House (Nancy Pelosi) and her allies have tried to callously harness the chaos of the moment for their own political gain,” they wrote.

In response, the House Democrats prosecuting Trump said, “We live in a nation governed by the rule of law, not mob violence incited by presidents who cannot accept their own electoral defeat.”

“The evidence of President Trump’s conduct is overwhelming,” the managers wrote. “He has no valid excuse or defense for his actions. And his efforts to escape accountability are entirely unavailing. As charged in the Article of Impeachment, President Trump violated his Oath of Office and betrayed the American people.”