Updated at 5:57 p.m. ET

The House impeachment managers accuse Donald Trump of summoning a mob to Washington, D.C., on Jan. 6, whipping the crowd "into a frenzy" and then aiming them "like a loaded cannon" at the U.S. Capitol, pinning the blame for the deadly violence that ensued directly on the former president.

The allegations are contained in a memo delivered to the Senate that presents an outline of the case against Trump that House impeachment managers plan to present on Feb. 9 when the trial begins.

Also Tuesday, Trump's lawyers filed an official response to the article of impeachment charging that Trump incited insurrection. In their 14-page filing, the former president's attorneys largely ignore the factual assertions contained in the House document, denying the allegation without presenting evidence, and asserting that it is up to the House to prove its case.

They argue that Trump did not incite the crowd on Jan. 6 "to engage in destructive behavior." They focus much of their reply on the argument that the Constitution's impeachment provision does not apply to a president who is no longer in office.

The dueling memos come a week ahead of Trump's second impeachment trial, although one key difference this time is that he has already been voted out of office.

In their 80-page brief, the House managers lay out their case against Trump and the grounds for convicting him even after he has left the White House.

"This trial arises from President Donald J. Trump's incitement of insurrection against the Republic he swore to protect," the House managers write.

"The House of Representatives has impeached him for that constitutional offense. To protect our democracy and national security — and to deter any future President who would consider provoking violence in pursuit of power — the Senate should convict President Trump and disqualify him from future federal officeholding."

The managers, led by Rep. Jamin Raskin of Maryland, argue that Trump is "singularly responsible" for the riot that overran the Capitol on Jan. 6, damaged the historic building and left five people dead.

"It is impossible to imagine the events of January 6 occurring without President Trump creating a powder keg, striking a match, and then seeking personal advantage from the ensuing havoc," they write.

The managers' memo creates a slow drum roll of facts intended to prove that Trump, as early as July, began planning to undercut any election result in which he did not win. The House memo, for instance, quotes Trump's repeated claims that the only way he would lose would be "if the election is rigged."

The events of Jan. 6

They walk through the lead-up to January 6, the day, when members of Congress were counting Electoral College votes, noting that for weeks, Trump refused to accept the results of the 2020 election and perpetuated baseless claims that he won in a landslide and the vote was "stolen" from him.

"He amplified these lies at every turn, seeking to convince supporters that they were victims of a massive electoral conspiracy that threatened the Nation's continued existence," they write. "But every single court to consider the President's attacks on the outcome of the election rejected them."

With his options dwindling, they say, Trump turned to the Jan. 6 rally in Washington. inviting his supporters to come to Washington, to "stop the steal."

The House managers say Trump took the stage after his lawyer Rudy Giuliani had called for "trial by combat," and Trump's son had warned Republican lawmakers not to finalize the election results, declaring, "We're coming for you."

"Finally, President Trump appeared behind a podium bearing the presidential seal. Surveying the tense crowd before him, President Trump whipped it into a frenzy, exhorting followers to 'fight like hell [or] you're not going to have a country anymore,' " the managers write. "Then he aimed them straight at the Capitol, declaring: 'You'll never take back our country with weakness. You have to show strength, and you have to be strong.' "

They continue: "Incited by President Trump, his mob attacked the Capitol. This assault unfolded live on television before a horrified nation."

The managers argue Trump did nothing to call the riot off, even when under pressure to do so, which they say was a "dereliction of duty." And his first statement about the violence, hours later, sent a dual message, telling his supporters to go in "peace" while also telling them, "You're very special."

Trump's legal team responds

In their own memo outlining key arguments, Trump's lawyers Bruce Castor Jr. and David Schoen push back against the House allegations.

They argue that the Constitution requires that a person be in office to be impeached, and since Trump no longer occupies the presidency, the impeachment trial in the Senate is unconstitutional.

Schoen and Castor also say that Trump's remarks to the crowd on Jan. 6 are protected speech under the First Amendment. As for the assertion that Trump was pushing baseless claims about fraud, his lawyers argue that "insufficient evidence" exists to conclude that Trump's claims are inaccurate.

Schoen and Castor are new to Trump's defense team; his previous top impeachment lawyers parted ways with the former president on Saturday.

House managers tackle the constitutionality question

The House managers, in their brief, directly address the constitutional arguments advanced by the defense.

They argue that there is precedent for holding former officeholders responsible for their actions through impeachment, although none of those instances involved a president.

In a vote last week that could foreshadow a final acquittal vote, 45 Senate Republicans voted that impeaching a former president is unconstitutional.

They also argue that common sense is in their favor, saying, "There is no 'January Exception' to impeachment or any other provision of the Constitution."

"Presidents do not get a free pass to commit high crimes and misdemeanors near the end of their term," they write. "The Framers of our Constitution feared more than anything a President who would abuse power to remain in office against the will of the electorate. Allowing Presidents to subvert elections without consequence would encourage the most dangerous of abuses."

The managers also tackle Trump's "free speech" defense over his remarks on Jan. 6.

The First Amendment protects private citizens from the government but not government officials from accountability, they say.

The First Amendment also doesn't prevent Congress from removing an official whose statements undermine government interests.

"No one would seriously suggest that a President should be immunized from impeachment if he publicly championed the adoption of totalitarian government, swore an oath of eternal loyalty to a foreign power, or advocated that states secede from and overthrow the Union — even though private citizens could be protected by the First Amendment for such speech," they argue.

Finally, even if Trump's actions while still in office were to be treated like the acts of a private citizen, he still wouldn't be protected by the First Amendment, they say, because speech that incites violence and lawless action is not protected.

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