WASHINGTON (NewsNation Now) — Nine House Democrats who will prosecute Donald Trump in his impeachment trial are making their most detailed case yet for why the former president should be convicted, arguing in a brief filed Tuesday that he bears “unmistakable” blame for last month’s deadly assault on the U.S. Capitol.

In a formal response to the House’s impeachment article, Trump denied the allegations through his lawyers and called the trial unconstitutional.

The House Democrats’ brief argues that when the trial opens before the Senate next week, the former president must be found guilty of inciting insurrection in his speech before the Jan. 6 riots. Five people died in the chaos, including a police officer who will lie in honor at the U.S. Capitol Tuesday evening.

“His conduct endangered the life of every single member of Congress, jeopardized the peaceful transition of power and line of succession, and compromised our national security,” the Democratic managers of the impeachment case wrote. “This is precisely the sort of constitutional offense that warrants disqualification from federal office.”

The House impeachment managers also rejected Republicans’ claims that it would be unconstitutional to put Trump on trial in the Senate after his term ended on Jan. 20.

“There is no ‘January Exception’ to impeachment or any other provision of the Constitution,” the impeachment managers wrote. “A president must answer comprehensively for his conduct in office from his first day in office through his last.”

Read the impeachment managers’ full arguments in the trial brief provided below:

Trump’s lawyers responded with their own filing, denying that he had incited the riot and arguing that the trial was unconstitutional now that his term has ended.

“It is denied that President Trump ever endangered the security of the United States and its institutions of Government,” defense lawyers wrote in a 14-page brief.

They also cited the First Amendment in defense of Trump disputing the election results.

Trump’s attorneys wrote that the former president “exercised his First Amendment right under the Constitution to express his belief that the election results were suspect, since with very few exceptions, under the convenient guise of Covid-19 pandemic ‘safeguards’ states election laws and procedures were changed by local politicians or judges without the necessary approvals from state legislatures.”

Read former President Donald Trump’s response to the impeachment article provided below:

The dueling filings offer the first public glimpse of the arguments that both sides intend to present at the impeachment trial.

Trump is just the third president to have been impeached, the first to be impeached twice and the first to face trial after leaving office. Members of the 100-seat Senate will serve as jurors in his impeachment trial, due to begin next week.

Trump has been sticking to unfounded claims that his election loss to Democratic President Joe Biden was the result of widespread fraud. Numerous federal and state courts have rejected those claims, including judges Trump appointed and members of his former administration.

The riots involving the former president’s supporters occurred while Congress was certifying Biden’s Nov. 3 election win.

Convicting Trump would require a two-thirds vote, meaning that 17 Republicans would need to join the Senate’s 50 Democrats in voting to convict.

Trump’s first impeachment trial, on charges of abuse of power and obstructing Congress arising from his phone call urging Ukraine to investigate Biden and his son Hunter, ended last year in acquittal by the then Republican-controlled Senate .

Forty-five Senate Republicans voted last week in support of a measure declaring the impeachment trial unconstitutional since it is occurring after Trump has left office. A conviction could lead to a second vote banning Trump from running for office again.

Reuters and the Associated Press contributed to this report.