The Senate has begun former US president Donald Trump’s second impeachment trial on a charge that he incited a deadly insurrection at the US Capitol on January 6.
Senators will engage in up to four hours of debate on the constitutionality of impeaching a former president.
Each side has two hours to make its case on Tuesday, after which the Senate is expected to vote and reject the Republican efforts to dismiss the trial.
They Democrats only need a simple majority to move forward.
Opening arguments from the House Democrats start on Wednesday and Mr Trump’s lawyers are expected to mount their defence starting on Friday.
Mr Trump’s lawyers say he is not guilty of the sole charge of “incitement of insurrection” and that his fiery words were just a figure of speech as he encouraged a rally crowd to “fight like hell”.
Prosecutors say he “has no good defence” and have promised to present new evidence.
Mr Trump is the first former US president to be tried after leaving office.
The House impeached Trump on January 13, a week before Democrat Joe Biden was inaugurated.
