The impeachment trial of U.S. President Donald Trump began in full Tuesday in the U.S. Senate, with a spirited debate over the rules governing the third such trial in U.S. history over whether a president should be ousted from the White House for allegedly violating his oath of office.

Trump's chief lawyer, White House counsel Pat Cipollone, called Senate Majority Leader Mitch McConnell's proposed timeline and parameters for the trial "a fair way to proceed," one that will result in the president's acquittal on two articles of impeachment because he has "done absolutely nothing wrong."

As the trial started, McConnell backed off his plan for 12-hour sessions from Wednesday through Saturday this week that could have kept the Senate in session late into the evening for four straight days.

Instead, he cut his proposed sessions back to eight hours each, with House managers prosecuting the case against Trump over three days, and Trump's lawyers defending him in another three days of eight-hour sessions.

The lead House manager, Congressman Adam Schiff, assailed McConnell's plan at length because it delays votes until later in the trial on whether to subpoena White House documents related to Trump's actions, and call as witnesses key Trump aides familiar with his actions in pressing Ukraine to launch investigations that would benefit him politically.

Schiff, chairman of the House Intelligence Committee, said that not voting on witnesses or subpoenaing documents at the trial's outset would make a "mockery" of the proceeding.

With no witnesses or new White House documents, Schiff said, "It's not a fair trial, or even a trial at all. Why should this trial be different than any other trial?"

In this image from video, impeachment manager Rep. Adam Schiff speaks during the impeachment trial of President Donald Trump, in the Senate, at the Capitol in Washington, Jan. 21, 2020.

Democrats are sharply contesting McConnell's plan, denouncing it as a "coverup" and "national disgrace,” although McConnell says he has enough Republican votes to push through the schedule he wants.

McConnell, who is working with Trump's lawyers on trial strategy in an effort to acquit him quickly, rebuffed claims his trial parameters are not fair, saying, “Here in the Senate, the president's lawyers will finally receive a level playing field with the House Democrats, and will finally be able to present the president's case.”

It is a plan that could lead to Trump's acquittal as soon as next week. A two-thirds vote in the Senate would be needed to convict Trump and oust him from the White House, but no Senate Republican has called for his removal.

McConnell and the Republicans have made no secret of wanting the trial to be as quick as possible. His initial resolution would have given Democratic House impeachment managers and Trump's legal team 24 hours each over two days to present their cases. Senate Minority Leader Chuck Schumer called McConnell's plan a "blueprint for an impeachment trial on fast forward."

McConnell also agreed that evidence collected by House impeachment investigators would be submitted to the Senate record, rather than leaving it an open question.

Fight to call witnesses

Schumer offered amendments during the Senate debate to subpoena White House documents and force testimony from Trump aides familiar with his efforts to press Ukrainian President Volodymyr Zelenskiy to investigate former Vice President Joe Biden and his son, Hunter.

Trump made his requests to Zelenskiy in a late July phone call at the same time he was temporarily blocking release of $391 million in military aid to Kyiv that it wanted to help fight pro-Russian separatists in eastern Ukraine.

After a 55-day delay, Trump released the assistance in September without Zelenskiy launching the Biden investigations. That was proof, Republicans say, that Trump did not engage in a reciprocal, quid pro quo deal — the Biden investigations in exchange for the military aid.

“Republican senators will face a choice of getting the facts or joining Leader McConnell and President Trump in covering them up," Schumer said.

President derides process

Trump has almost daily assailed the impeachment effort against him, including in Davos, Switzerland, where he is attending the World Economic Forum.

“That whole thing is a hoax,” he told reporters. “It goes nowhere, because nothing happened. The only thing we’ve done is a great job. … That whole thing is a total hoax, so I’m sure it’s going to work out fine.”

Later, he said on Twitter, in all caps, "READ THE TRANSCRIPTS!" referring to a rough White House account of his July call with Zelenskiy, according to Donald J. Trump @realDonaldTrump.

In the hours ahead of the Tuesday session, House managers told Cipollone that he might be a material witness during the trial since his office played a role in handling some of the Ukraine-related issues as they emerged in the latter half of 2019. The Democratic lawmakers said Cipollone should disclose what role he played.

Trump's lawyers are assailing the impeachment case against him as a "dangerous perversion of the Constitution," asserting he did "absolutely nothing wrong" in pressing Ukraine to launch investigations to benefit himself politically.

The lawyers say Democrats pushing for Trump's removal are not trying to find the truth about Trump's Ukraine-related actions, but are looking to overturn his 2016 election and interfere with his 2020 reelection campaign.

The charges

The House of Representatives impeached Trump on two articles. One alleges he abused the presidency by pressing Zelenskiy for the Biden investigations. The other is that he allegedly obstructed Congress in its investigation of his Ukraine-related actions.

Democratic lawmakers had earlier said it was clear that the "evidence overwhelmingly establishes" that Trump is guilty of both charges.

The Trump lawyers, in their 110-page filing on Monday, said the president was conducting normal foreign policy affairs in dealing with Zelenskiy.

At least 20 of the 53 Senate Republicans would have to join all 47 Democrats to convict Trump. The trial could last much longer if Democrats succeed in persuading four Republicans to join them in calling for testimony from key Trump aides about the president's Ukraine-related actions.

Democrats want to hear testimony from former national security adviser John Bolton, acting White House chief of staff Mick Mulvaney and others.

Trump has said he wants to call the Bidens as witnesses, along with the still-unidentified whistleblower who first disclosed Trump's July 2019 phone call with Zelenskiy. On Twitter Monday, he seemed averse to hearing testimony from Bolton, whom he ousted in September.

Democrats, Trump said, "didn’t want John Bolton and others in the House" to testify. "They were in too much of a rush. Now they want them all in the Senate. Not supposed to be that way!"

House Democrats had sought testimony from Bolton and others in Trump's orbit. But the potential witnesses complied with the president's edict to not cooperate with their investigation, although others ignored it and testified.

Democratic lawmakers abandoned efforts to subpoena some witnesses out of fear that the legal fights over their testimony would extend for months.

Bolton now says he is willing to testify at Trump's impeachment trial if he is subpoenaed by the Senate.

Two other presidents — Andrew Johnson in 1868 and Bill Clinton in 1998 — were impeached by the House but acquitted in Senate trials, and remained in office.

U.S. President Richard Nixon faced almost certain impeachment in 1974 in the Watergate scandal, but resigned before the House acted. (VOA)

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