How Trump’s Impeachment Trial Will Unfold

The second Senate impeachment trial of Donald J. Trump will open on Tuesday, just over a month after the Jan. 6 assault on the Capitol the House has charged him with inciting. Senate leaders were still haggling on Monday over final details, but they were closing in on a plan for an exceptionally speedy proceeding that could conclude in less than half the time of his first.

Monday was the final day for pretrial motions, and Mr. Trump’s lawyers laid out his defense in a 78-page brief submitted to the Senate, denying that he was responsible for the attack and arguing that in any case, an ex-president could not be tried by the Senate.

In their own filing, the House Democrats who are prosecuting him reiterated their allegation that Mr. Trump “willfully” incited the riot and insisted that he was subject to a Senate impeachment trial.

Here is a broad overview of how the trial will unfold under the rules being discussed.

Tuesday: Four hours of debate, then a procedural vote.

The first public clash between the president’s legal team and the impeachment managers will be over the question of whether the trial is even legitimate under the Constitution.

Senators are planning to allow up to four hours of debate between the managers and defense team on the question that has loomed over the proceedings — whether a former president can be tried by the Senate for high crimes and misdemeanors. No former president has ever been, but the Senate did try a war secretary in the 1870s after he left office.

If a simple majority of senators agree to move forward, as expected, the main part of the trial begins.

Wednesday to Friday or Sunday: 16 hours of oral arguments per side.

The prosecution and defense each have up to 16 hours to present their cases, likely starting at noon on Wednesday under the terms of the deal being discussed by Senators Chuck Schumer, Democrat of New York, and Mitch McConnell, Republican of Kentucky.

Neither side is expected to take the fully allotted time. But because one of Mr. Trump’s lawyers requested that the trial pause Friday at sundown for the Jewish Sabbath, which ends at sundown on Saturday, it is unclear if the presentations will be completed before or on Sunday.

Sunday to early the following week: Senators questions, a possible debate over witnesses and possibly a verdict.

The sequence of what happens next is less certain.

Traditionally, senators are allowed at least a day to question the prosecution and defense after they present their cases.

This time, senators also appear willing to give the House managers the option to debate and vote on calling witnesses. It is unclear if they will avail themselves of that option.

Mr. Trump declined last week to accept the Democrats’ offer to testify voluntarily at his trial, but the managers have yet to decide whether they will try to subpoena him or any other witness. Doing so could bolster their case, but Democrats are also eager to quickly resume their push to pass the Biden administration’s $1.9 trillion coronavirus relief package.

Whenever the witness question is resolved, the trial is likely to conclude with closing arguments and a final, up-or-down vote on whether to convict Mr. Trump.