Lawmakers will meet at 1 p.m. Eastern time to listen to four hours of debate on the matter, which will be evenly divided between the 10 Democratic House impeachment managers and Trump’s defense team led by David Schoen and Bruce Castor Jr.

The event can be watched on C-SPAN starting at 12:55 p.m. Eastern time, or at the link below, provided by the PBS Newshour.

The case arrives in the Senate after the House of Representatives voted last month to charge Trump with “incitement of insurrection” after a mob of his supporters stormed the U.S. Capitol on January 6. Five people died in the riot, including one law enforcement officer.

The attack coincided with a joint session of Congress to certify President Joe Biden’s electoral victory. Before the violence began, Trump addressed his supporters at a “Save America” rally and told them “we will never concede” and to “fight like hell.”

In a 78-page brief filed on Monday, the former president’s defense team continued its central argument that the upcoming trial should be dismissed out of hand as unconstitutional since Trump no longer occupies the Oval Office.

“In the past, Congress has acknowledged and exercised its duty to not impeach when an official is no longer in office,” the brief read. “In the case involving the impeachment of President Richard M. Nixon, Congress decided not to impeach because he resigned from office.”

His team also argued that his actions surrounding the January 6 insurrection are protected by the First Amendment right to free speech. The attorneys noted Monday Trump only used the word fight a handful of times and argued it was used “in the figurative sense that has long been accepted in public discourse.” They also pointed to his remark urging supporters to “peacefully and patriotically make your voices heard.”

“President Trump did not direct anyone to commit lawless actions, and the claim that he could be responsible if a small group of criminals (who had come to the capital of their own accord armed and ready for a fight) completely misunderstood him, were so enamored with him and inspired by his words that they left his speech early, and then walked a mile and a half away to ‘imminently’ do the opposite of what he had just asked for, is simply absurd,” the brief read.

The House impeachment managers, led by Representative Jamie Raskin of Maryland, rebutted these assertions in a five-page response on Monday in which they asserted his free speech defense was “utterly baseless.”

“The evidence of President Trump’s conduct is overwhelming. He has no valid excuse or defense for his actions. And his efforts to escape accountability are entirely unavailing,” the 10 Democratic managers wrote.