Here is what can be expected in the coming days and weeks
The United States House of Representatives on Wednesday formally handed off two articles of impeachment against President Donald Trump to the Senate, clearing the way for a trial.
The House of Representatives impeached Trump on December 18 for abuse of power related to his efforts to get Ukraine to launch an investigation into his political rival, former Vice President Joe Biden, and obstruction of Congress for his refusal to participate in the impeachment inquiry. Trump has denied any wrongdoing.
Here is what can be expected in the coming days and weeks:
The newly appointed House "managers," who will prosecute Trump, was due to go to the Senate chamber and read the resolution appointing them and the two articles of impeachment in full. Then the Senate was due to take up the articles of impeachment.
Starting January 21
House managers will present their case against Trump, and the president's legal team will respond, with senators sitting as jurors. Majority Leader Mitch McConnell has said the Senate will sit in session six days a week, taking only Sundays off.
Senators would then be given time to submit questions to each side.
McConnell has said that, once the charges are formally submitted to the Senate, he will back a resolution that would set initial rules for the trial but postpone a decision on whether to hear from witnesses.
McConnell has not yet published a draft of the resolution, but he said it would be similar to one adopted in January 1999 during the impeachment of Democratic former president Bill Clinton.
That resolution set deadlines for the prosecution and defence to submit “trial briefs” that laid out their cases in writing. The resolution also allocated 24 hours for representatives of each side to make oral arguments and set aside 16 hours for senators to ask them questions.
The Clinton resolution referenced by McConnell did not resolve whether witnesses would be called. A follow-up resolution allowing for three witnesses to testify in videotaped depositions passed later along a party-line vote.
Late January to early February
Democrats will push to hear from witnesses during the trial. If McConnell's resolution on initial trial rules is adopted, as expected, senators would likely vote some time after the trial has started on whether to introduce witness testimony sought by the Democrats. Republicans could seek to call witnesses of their own as well, though the White House said on Thursday it didn't think witnesses are necessary.
The Senate now has 53 Republicans, 45 Democrats and two independents who usually vote with the Democrats. That means four Republicans would need to cross party lines and join Democrats in requesting witness testimony.
The trial could continue into February, when Iowa and New Hampshire hold the first nominating contests for the 2020 presidential election. That could pose logistical problems for the four senators seeking the Democratic nomination: Bernie Sanders, Elizabeth Warren, Amy Klobuchar and Michael Bennet.