Trump's second impeachment trial -- the first for a former president -- resumes Friday at noon with arguments from Trump's defense attorneys who are making their case that Trump is not guilty for incitement of insurrection.

The public should expect to see four attorneys on the Trump team: David Schoen, Bruce Castor, Michael van der Veen and Julieanne Bateman. They're expected to argue the trial is unconstitutional because Trump is no longer in office -- despite the Senate already voting to affirm it has the authority -- and that Trump's use of social media and comments made on Jan. 6 are protected by the First Amendment. They've also signaled they'll only use three or four hours of their allotted time.

Sen. Bill Cassidy, R-La., who joined Democrats and five other Republicans in voting that the trial is constitutional -- changing his vote from an earlier motion on the issue -- said he hopes the defense team can explain the timeline of events and Trump's repeated assertions that the election was stolen.

House impeachment managers, over the past two days, argued that Trump spent months priming supporters to storm the Capitol on Jan. 6, in a last-ditch effort to overturn the election results after failed attempts to compel local, state and federal law enforcement and election officials to do so, and that he showed a "lack of remorse."

They also used never-before-seen Capitol security footage of senators, House members and former Vice President Mike Pence fleeing the chambers during the riot -- reminding lawmakers of when many of them were fearing for their lives.

Democrats would need at least 17 Republicans to side with them in order to convict Trump and bar him from federal office, but the majority of Republicans have already signaled they will vote to acquit, despite evidence of the attack showing several of them may have also been targets.

Truths are less in question than consequences in Trump's second impeachment trial.

In wrapping their case, House managers argued for Trump's conviction in part by talking about what it would mean to do nothing.

"I'm afraid he's going to run again and lose, because he can do this again," Rep. Ted Lieu, D-Calif., warned in his presentation Thursday.

"Impeachment is not to punish, but to prevent," said Rep. Diana DeGette, D-Colo.

Now comes Trump's defense, in what could be a single day of arguments in a trial that could even wrap on Friday or Saturday. The former president's lawyers are conceding critical facts rather than suggesting alternative ones.

They have not sought to call election results into question and say they will not defend the actions of the riotous mob that took over the Capitol Jan. 6. Where they draw the line -- and where they are asking Republicans to hold it -- is on whether Trump's actions should be punished through this particular means.

Part of their argument carries a warning on what will happen if tens of millions of voters feel disenfranchised. Trump attorney Bruce Castor employed two different metaphors earlier this week: "The floodgates will open. I was going to say, 'release the whirlwind.'"

Voting to acquit might still seem like the easier path for Republicans, given Trump's enduring appeal to GOP voters. But as Jan. 6 made clear, there are more than simple political consequences to consider.

-ABC News Political Director Rick Klein

Just hours before Donald Trump's attorneys are to launch their defense of the former president in his Senate impeachment trial, sources tell ABC News that there is growing tension within the legal team.

Sources with direct knowledge of the situation tell ABC News that Trump wants attorney Bruce Castor to have a reduced role in the presentation in favor of co-counsel David Schoen, which they say is leading to some infighting. Multiple sources close to Trump say they are hoping that Schoen takes control and wraps up the defense's presentation on Friday.

Neither Castor, Schoen or representatives of the former president immediately responded to inquiries from ABC News seeking comment.

Trump defense attorney David Schoen, when leaving the Capitol on Thursday after House impeachment managers wrapped their arguments, said the defense would use around "three or four hours" allotted to them on Friday, signaling the trial could wrap by the end of the day.

"The evidence they [House impeachment managers] have, under no circumstances, would make out a case for incitement. I thought that the argument we heard today from Congressman Raskin about what he understands the law to be was as dangerous a -- was as dangerous a formulation as I have ever heard," Schoen said, saying it puts every senator in the chamber who wishes to speak freely at risk.

"There’s sort of a false dichotomy here. Either you condemn what he said, and, and, you know, find him guilty. There’s no middle ground, there’s no possibility of thinking what he said maybe, you know, was inappropriate," Schoen continued of the trial.

He said Trump's rhetoric on Jan. 6 shouldn't be seen as incitement.

"It's a powerful speech, but when he uses the word 'fight,' most of the times during the speech, it's clear he's talking about legislators fighting for our rights, people fighting to advocate and -- and, you know, everyone likes to overlook the word 'peacefully' in there," Schoen said.

Asked if he thinks Trump should have spoken out sooner as the siege continued, he said, "When we look back, I think there are a lot of, a lot of things that people could have done differently, probably."

"We're starting to learn now is that apparently there were some warnings to the Capitol Police ahead of time. They apparently made some inquiry into the House, and reinforcements weren't provided when they should have been," Schoen added.

He maintained that Trump, in Florida, remains "upbeat."

-ABC News' Trish Turner and Katherine Faulders

After the Senate decided it will not call any witnesses, lead House manager Rep. Jamie Raskin, D-Md., was the first to speak during closing arguments. He reiterated the prosecution's case, calling for the conviction of Trump.

"It was suggested by defense counsel that Donald Trump's conduct during the attack, as described in Congresswoman Beutler's statement, is somehow not part of the Constitutional offense for which former President Trump has been charged," Raskin began. "I want to reject that falsehood and that fallacy immediately. After he knew that violence was underway at the Capitol, President Trump took actions that further incited the insurgents to be more inflamed and to take even more extreme, selective, and focused action against Vice President Mike Pence."

Raskin went on to use his time to describe Trump's months-long campaign to discredit the 2020 election results by spreading misinformation, which he argued laid the groundwork for deadly events of Jan. 6. He went on to claim that the former president assembled the mob, incited it and then sent it off to the Capitol during his speech. At every point, Trump sided with the insurrectionists rather than the Congress, Raskin said.

Once when the violence began, Raskin declared that Trump ignored the violence and further incited it by aiming the attacks on his own vice president.

"There has never been a greater betrayal by the president of the United States of his office, and of his oath to the Constitution."

Raskin then took a moment to suggest the GOP used "cancel culture" against one of its leaders, Rep. Liz Cheney, R-Wyo., who voted to impeach Trump in the House.

"Liz Cheney is a hero for standing up for the truth, and resisting this retaliatory cancel culture that she was subjected to."

Raskin emphasized his gratitude toward the Capitol Police, and finished his argument by saying convicting Trump is a vote for the "security of our democracy."

"They attacked this building, they disrupted the peaceful transfer of power, they injured and killed people, convinced that they were acting on his instructions, and with his approval, and protection," Raskin finished. "And while that happened, he further incited them, while failing to defend us. If that's not ground for conviction, if that's not a high crime and misdemeanor against the republic in the United States of America then nothing is. President Trump must be convicted for the safety and security of our democracy and our people."