Trump is the first U.S. president to be impeached twice and the first to face trial after leaving office. If convicted, the Senate could then vote to bar him from running for office again.
Conviction is seen as unlikely, however, as at least 17 Republicans in the 100-seat chamber would have to join all 50 Democrats to find the former president guilty.
Only six Republicans voted with Democrats to move forward with the trial, rejecting an argument made by other Republican Senators that the Constitution does not allow Congress to impeach a president who has already left office.
The Senate is due to convene at 10 a.m. (1500 GMT), and a final vote could come in the afternoon.
The trial has highlighted the extraordinary danger lawmakers faced on Jan. 6, when Trump urged his followers to march to the Capitol and “get wild” in an effort to prevent lawmakers from certifying his defeat to Democrat Joe Biden in the presidential election. Five people died in the chaos.
Security-camera footage shown at the trial showed rioters came perilously close to lawmakers as they were evacuated from the Senate and the House of Representatives.
Among those targeted was Vice President Mike Pence, who had refused Trump’s entreaties to interfere with the proceedings earlier that day.
Trump criticized Pence on Twitter as lacking “courage” shortly after Republican Senator Tommy Tuberville told Trump that the vice president was being evacuated for his own safety.
Trump’s lawyers gave conflicting answers on Friday when asked if Trump knew Pence was in danger when he issued his tweet. Several Republican senators said they still had questions about Trump’s role.
“The issue is what was the president’s intent, right? Only the president could answer. And the president chose not to,” Republican Senator Bill Cassidy told reporters. He said he had not made up his mind on how to vote.
Trump refused to testify in the trial.
MARCHING ORDERS
House Democrats making the case for impeachment have argued that Trump set the stage for violence through repeated — and baseless — claims that the election results were fraudulent. They say he summoned the mob to Washington, gave the crowd its marching orders and did nothing to stop the violence as it played out on television.
Trump’s defense lawyers have argued that Trump’s activity was allowable under free-speech protections in the U.S. Constitution.
“I don’t know, at this point, how many minds get changed,” Senator John Thune, the chamber’s No. 2 Republican, told reporters on Friday.
As many as 10 Republicans could find Trump guilty, according to a Senate aide, which would still be short of the 67 votes needed for conviction. Republican Senate Leader Mitch McConnell, who reprimanded Trump after the Jan. 6 attack, remains a question mark.
Trump’s first impeachment trial, which stemmed from his efforts to pressure Ukraine to investigate Biden, ended in an acquittal a year ago in what was then a Republican-controlled Senate.
Trump remains popular among conservative voters, and some say they are angry that more elected Republicans did not support his effort to overturn the election.
“I don’t think there’s any salvation for the Republican Party. It’s time to burn it down and start over,” said North Carolina resident Adam Silva, who said he switched his voter registration to “unaffiliated” after Congress certified Biden’s victory.
Lawmakers from both parties have said they would like to wrap the trial up quickly so they could move on to other business, such as confirmation votes on senior Biden administration officials and a $1.9 trillion coronavirus aid package.
With initial presentations complete, the prosecution or the defense could call witnesses on Saturday to bolster their cases. Neither side has said whether they will do so.
After that, the prosecution and defense teams get two hours each for closing statements. Defense lawyer Bruce Castor said he only planned to use half of his alloted time.
That means a final vote on conviction could come as soon as early afternoon.
