Democrats on Monday made good on their threat to file an article of impeachment against President Donald Trump, putting him on track to become the first US leader to face impeachment twice.
Impeachment would force Mr Trump to face a Senate trial over his role in inciting the mob that ransacked Capitol Hill last week.
But it is unlikely to achieve the Democrats’ objective of removing him from power before president-elect Joe Biden takes office on January 20.
House Democrats, led by David Cicilline, Jamie Raskin and Ted Lieu, filed the resolution to impeach Mr Trump on Monday.
The resolution charges the president with "incitement of insurrection", accusing him of using his rally last week to encourage the Capitol Hill rioters to try to stop Congress certifying Mr Biden's election victory.
Democrats have quickly gathered in support of the resolution and the House could vote as soon as Wednesday to impeach Mr Trump.
But even in the likely event that the House does so this week, the Senate is likely to protect the president from facing trial during his final nine days in office, because of Republican opposition.
Majority leader Mitch McConnell distributed a memo to Senate Republicans last week, saying that the chamber is in recess until January 19 – the day before Mr Biden’s inauguration.
Convening the Senate before then would require unanimous consent from all 100 senators, which is unlikely.
But if the House sends the article of impeachment to the other side of Capitol Hill, the Senate would still be constitutionally required to hold an impeachment trial for Mr Trump.
And after that trial, the Senate could vote to bar him from holding federal office again.
Mr Trump has strongly hinted that he intends to run for a second term as president in 2024.
A Senate conviction could force Mr Trump out of the Republican presidential primary field, but only if two thirds of Congress voted to convict him after the trial.
Only 48 senators voted to convict him after his impeachment trial last year.
A trial also threatens to bog down the Senate calendar at a time when Mr Biden will need his party’s new, razor-thin control of the chamber to confirm his Cabinet and start enacting his agenda.
But the House could also delay sending the article of impeachment to the Senate, ensuring there is no immediate trial and giving Mr Biden more flexibility to manoeuvre in the early days of his new administration.
House majority whip Jim Clyburn suggested on CNN on Sunday that Democrats should vote on impeachment, then postpone transferring the article to the Senate until after Mr Biden’s first 100 days in office.
Last year, House Speaker Nancy Pelosi delayed transferring the articles of impeachment for several weeks before sending them to the Senate.
Timing aside, Democrats are virtually guaranteed to set the parameters for the trial, as Republicans will no longer hold control of the Senate after next week.
Newly elected Senate Democrats Raphael Warnock and Jon Ossoff are due to take office at some point before Georgia's January 22 election certification deadline.
This will evenly split control of the Senate between 50 Democrats and 50 Republicans.
Vice president-elect Kamala Harris will cast any tie-breaking votes when she takes office on January 20.