The US Senate began its impeachment trial of President Donald Trump on Tuesday afternoon. The House "manager" team, which acts as a prosecutor, and Trump's lawyers engaged in a heated debate over the trial schedule and rules.

(Photo: Xinhua)

At issue is whether to introduce new witnesses and documents at the start of the Senate trial. Under the trial rules proposed by Senate majority leader Mitch McConnell, the Senate will not introduce new witnesses or documents at the start of the impeachment trial. McConnell warned about subpoenas for witnesses and documents, saying that “pursuing those witnesses” sought by Democrats “could indefinitely delay the Senate trial.” According to CNN, McConnell hopes to wrap up the trial process in about 10 days.

Senate minority leader Chuck Schumer criticized McConnell's plan as a "national disgrace" aimed at quickly acquitting the president. Democrats say they want to subpoena former White House national security advisor John Bolton, acting White House chief of staff Mick Mulvaney and others to testify before the Senate. In addition, Democrats are also demanding the introduction of documents from the White House, State Department, Pentagon, Energy Department and Office of Management and Budget.

On Tuesday afternoon, Schumer filed a series of amendments to change McConnell's rule resolution. At the moment, the Senate is still debating and voting on the amendments. When today's hearing ends will depend on how many amendments Schumer eventually proposes. Earlier, McConnell said he had enough votes to block Democrats' calls for changes to the rules. So far, all the amendments raised by Schumer have been voted down along party lines.

McConnell's plan would give each side of the case three working days and a total of no more than 24 hours to make their case in the Senate. After the presentation, Senators, who act like jurors, can question both sides for up to 16 hours. After that, the two sides will split four hours between them to debate whether new witnesses or documents need to be called.

In addition, the rules of the trial also require Senators to remain silent during the presentation process, which will be conducted entirely by the House "manager" team and Trump's lawyers.

McConnell's original plan provided for only two working days for each side to make public statements. According to US media reports, the rule has not only angered Democrats, but also upset some GOP senators, as the tight schedule is bound to drag the presentations into midnight, which will affect the American public's viewing. In the updated version plan submitted on Tuesday, the time granted to both parties has been changed to 3 working days each, but the total presentation time of each party still shall not exceed 24 hours.

In addition, McConnell made another last-minute rule change to allow evidence gathered during the House impeachment investigation to automatically be included in the Senate trial record. Under previously issued trial rules, evidence gathered by the House must pass a vote before it can be added to Senate records.