With the US House of Representatives poised to impeach President Donald Trump for a second time -- just days before he is to leave office -- questions are being raised about what happens next.
Here are some of the possible scenarios if the House, as expected, impeaches Trump on Wednesday for inciting last week's attack by his supporters on the US Capitol as Congress certified Democrat Joe Biden's presidential election victory:
- Senate trial -
The usual process is for the Senate to hold a trial for a president who has been impeached by the House.
That's what happened last year after Trump was impeached by the Democratic-controlled House for pressuring the leader of Ukraine to dig up political dirt on Biden.
Trump was acquitted by the Republican-majority Senate.
This time, however, Trump has only a week left in the White House and Biden is to be sworn in as the 46th president of the United States on January 20.
That time crunch has sparked debate and speculation about whether the Senate can hold a trial before Trump leaves office.
- Call Senate back early? -
The Senate is in recess and is not scheduled to return until January 19.
Republican Senate Majority Leader Mitch McConnell has said a trial could not begin until January 20 -- the day Trump is scheduled to leave office.
According to McConnell's office, bringing the Senate back early would require the unanimous consent of all 100 senators -- an unlikely scenario.
Democrats disagree.
According to the office of Democratic Senate Minority Leader Chuck Schumer, a 2004 resolution allows the Senate to be brought back for emergency session with the consent of both the Majority and Minority leaders.
"There is nothing to prevent the Senate from taking it up immediately if Senate Majority Leader Mitch McConnell decides that he wants to proceed," Democratic Representative James McGovern of Massachusetts, the chairman of the House Rules Committee, said Wednesday.
- Pelosi and McConnell -
If Trump is impeached by the House, it is up to Nancy Pelosi, the Democratic speaker of the House, to decide when to send the article of impeachment to the Senate.
She could send it over immediately once it is passed on Wednesday or she could wait, as some Democrats have suggested, until after Trump leaves office and Biden is comfortably in place.
Once it reaches the Senate, McConnell's intentions are unclear.
The powerful Republican senator from Kentucky thwarted the last bid to convict Trump in the Senate, managing to rally all Republican senators with the exception of Mitt Romney of Utah to vote for acquittal.
But The New York Times reported on Wednesday that McConnell believes Trump did commit impeachable offenses and sees an opportunity to rid the Republican Party of the real estate tycoon once and for all.
A two-thirds majority of the senators present is needed to convict the president, meaning that if all of them are in the chamber at least 17 Republicans would have to join Democrats in voting for conviction.
- Post-presidency trial? -
If the Senate is unable to hold a trial before Trump leaves the White House on January 20 the question arises as to whether he can be tried after leaving office.
This has never happened before and some constitutional scholars argue that an ex-president cannot be tried by the Senate.
All three previous presidential impeachments -- those of Trump and presidents Andrew Johnson and Bill Clinton -- occurred while the leaders were still in the White House.
Like Trump, both Johnson -- in 1868 -- and Clinton -- in 1998-99 -- were impeached by the House but acquitted by the Senate.
But the House has impeached and the Senate has tried former senators and judges after they were no longer in office or on the bench.
One of the arguments being made for putting Trump on trial even after he leaves office is that a conviction could prevent him from ever holding federal office again.
Trump has expressed interest in potentially running for president again in 2024 and a simple majority vote of the Senate could bar him from another White House run.