Now that U.S. President Donald Trump has been impeached for a second time, the Senate will hold a very different trial than the last one as it enters uncharted territory to consider whether to bar him from future office.
After the House of Representatives made Donald Trump the first president in U.S. history to be impeached twice, he now faces another Senate trial - this time - to determine whether or not he incited an insurrection.
But there are several other key differences and more historic firsts to come in Trump’s second impeachment trial, says Reuters Legal Correspondent Jan Wolfe.
WOLFE: "This is a very unusual impeachment because it's going to be of Trump after he's left office.
Trump and his defenders have already argued that you can't impeach a former official, in the sense that you can't have a Senate trial for a former official.
But most legal experts reject that.
And they say it makes sense as a matter of policy, because it can result in Trump's disqualification from future office." In the trial, Trump's legal team is likely to argue that his remarks before his supporters stormed the Capitol were not a call to violence and were protected under the First Amendment.
But some legal experts say that's beside the point.
WOLFE: "All sorts of First Amendment protected speech could be grounds for impeachment.
I mean, if we had a president using racial slurs and promoting fascism and denying the Holocaust, nobody disputes that that president could be impeached.
But that's all protected by the First Amendment.
Incitement for purposes of the Senate trial is whatever Congress wants it to be.
So if Congress thinks that Trump incited an insurrection, that his speech provoked that attack on the Capitol, they can convict him." At least 17 Republicans would have to join the Democrats to convict Trump.
And more Republican senators have said they'd consider doing so this time around.
WOLFE: "One big difference with Trump's second impeachment that's underway is there's more bipartisan support.
In the House, which effectively charged Trump, we had 10 Republicans join with Democrats and say, you know, we see an impeachable offense here and in the Senate, which will conduct a trial to determine Trump's guilt, we could see quite a few Republicans cross party lines.
Maybe not not enough to convict him, but more than last time when we only had one Republican Senator, Mitt Romney of Utah, who joined Democrats in condemning Trump." While the Senate would need a two-thirds majority to convict Trump, historical precedent suggests the Senate would only need a simple majority to disqualify him from holding office in the future.
But Wolfe says few really know how that would play out in this case.
WOLFE: "There's going to be some debate about the proper vote threshold for disqualification.
There will be debate about whether you can disqualify if you don't first convict.
So we are definitely in some uncharted legal territory here.
There's not a lot of court rulings to rely on.
And for that reason, I would be wary of anyone who says they're absolutely certain about what the rules of engagement are going to be." The House impeached Trump in 2019 on charges of abuse of power and obstruction of Congress stemming from his request that Ukraine investigate his political rival, now his successor.
That made Trump the third U.S. president to be impeached, but no president has ever been convicted in a a Senate trial.