FILE - Attorney Alan Dershowitz leaves Manhattan Federal Court in New York, March 6, 2019. Dershowitz is among the lawyers representing President Donald Trump in his impeachment trial.
FILE - Attorney Alan Dershowitz leaves Manhattan Federal Court in New York, March 6, 2019. Dershowitz is among the lawyers representing President Donald Trump in his impeachment trial.

WASHINGTON - Key players in the impeachment trial of U.S. President Donald Trump and his defense argued sharply Sunday whether his efforts to get Ukraine to launch investigations to benefit him politically were impeachable offenses that warranted his removal from office.

Trump’s Senate trial formally opened last week and is set to hear opening arguments on Tuesday. But combatants in the political and legal fight over Trump’s fate waged verbal battles across the airwaves on Sunday morning news talk shows in the U.S. that offered a glimpse of the Senate drama the American public will witness in the days ahead.

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Criminal defense lawyer Alan Dershowitz, one of the team of lawyers defending Trump, told CNN’s “State of the Union” show that he will tell the 100 members of the Senate, who are acting as jurors deciding Trump’s fate, that “even if the facts as presented are true, it would not rise to the level of impeachment” to convict Trump and oust him from office.

The lawmakers will be deciding whether Trump committed “high crimes and misdemeanors,” the standard the U.S. Constitution set for removing a president from office. As the trial nears, the Republican-majority Senate remains highly unlikely to convict Trump, a Republican, since a two-thirds vote against Trump would be necessary to oust him from the White House.

FILE - Ukraine's President Volodymyr Zelenskiy and U.S. President Donald Trump face reporters during a bilateral meeting on the sidelines of the 74th session of the United Nations General Assembly in New York, Sept. 25, 2019.

Trump last July asked Ukrainian President Volodymyr Zelenskiy to launch an investigation of one of his top 2020 Democratic challengers, former Vice President Joe Biden, his son Hunter Biden’s work for a Ukrainian natural gas company, and a debunked conspiracy theory that Ukraine sought to undermine Trump’s 2016 campaign.  The phone call between the two leaders happened at the same time Trump was temporarily blocking release of $391 million in military aid Kyiv wanted to help fight pro-Russian separatists in eastern Ukraine.

Dershowitz argued that Trump’s actions did not amount to criminal conduct. He said that “if my argument prevails” and the Senate decides no impeachable offenses occurred, “There’s no need for witnesses” at Trump’s Senate trial and “the Senate should vote to acquit [Trump] or dismiss” the case against him.

FILE - House Intelligence Committee Chairman Adam Schiff, D-Calif., speaks during a news conference on Capitol Hill in Washington, Dec. 3, 2019.

Congressman Adam Schiff, the leader of seven House of Representative managers prosecuting the case against Trump, told ABC News’ “This Week” show, “The facts aren’t seriously contested, that the president withheld hundreds of millions of dollars in military aid to an ally at war with Russia, withheld a White House meeting that the president of Ukraine desperately sought to establish with his country and with his adversary the support of the United States in order to coerce Ukraine to helping him cheat in the next election.”

Schiff added, “They really can’t contest those facts. So the only thing really new about the president’s defense is that they’re now arguing that because they can’t contest the facts that the president cannot be impeached for abusing the power of his office.”

On Saturday, both the House lawmakers pushing for Trump’s conviction, and Trump’s defenders, filed legal arguments in the case.

The House managers said it was clear that the “evidence overwhelmingly establishes” that Trump is guilty of both charges in the two articles of impeachment he is facing.

FILE - President Donald Trump listens to a question during an event on prayer in public schools, in the Oval Office of the White House, Jan. 16, 2020, in Washington.

Meanwhile, Trump’s legal team called the impeachment effort against him “a dangerous attack on the right of the American people to freely choose their president.''

His lawyers called the impeachment effort “a brazen and unlawful attempt to overturn the results of the 2016 election and interfere with the 2020 election, now just months  away.”

But Schiff, chairman of the House Intelligence Committee that heard weeks of testimony about Trump and his aides’ attempts to pressure Ukraine for the Biden investigations, said the White House legal stance is “surprising in that It doesn’t really offer much new beyond the failed arguments we heard in the House."

"So the only thing really new about the president’s defense is that they’re now arguing that because they can’t contest the facts that the president cannot be impeached for abusing the power of his office,” Schiff said. “That’s the argument I suppose you have to make if the facts are so dead set against you. You have to rely on an argument that even if he abused his office in this horrendous way that it’s not impeachable. You had to go so far out of the mainstream to find someone to make that argument you had to leave the realm of constitutional law scholars and go to criminal defense lawyers."

FILE - House Speaker Nancy Pelosi of Calif., signs the resolution to transmit the two articles of impeachment against President Donald Trump to the Senate for trial on Capitol Hill in Washington, Jan. 15, 2020.

The Senate has yet to decide whether it will hear witnesses in the impeachment trial, with new testimony opposed by Senate Republican leader Mitch McConnell.

Democrats want to subpoena former national security adviser John Bolton, acting White House chief of staff Mick Mulvaney and others to testify about their knowledge of Trump’s Ukraine actions. Trump eventually released the Ukraine military aid in September after a 55-day delay without Zelenskiy launching the Biden investigations, which Republicans say is proof that Trump did not engage in a reciprocal quid pro quo deal — the military aid in exchange for the investigations to help him politically.

"We’ll be fighting for a fair trial,” Schiff said. “That is really the foundation on which this all rests. If the Senate decides, if Senator McConnell prevails and there are no witnesses, it will be the first impeachment trial in history that goes to conclusion without witnesses.”

He said, “We don’t know what witnesses will be allowed or even if we’ll be allowed witnesses. The threshold issue here is, will there be a fair trial? Will the senators allow the House to call witnesses, to introduce documents. That is the foundational issue on which everything else rests. There is one thing the public is overwhelmingly in support of and that is a fair trial.”

One of Trump’s staunchest Senate defenders, Sen. Lindsey Graham, on the “Fox News Sunday” show, called the impeachment effort “a partisan railroad job. It’s the first impeachment in history where there’s no allegation of a crime by the president.”

He said if Democrats demand to hear testimony from Bolton, Mulvaney and others, Trump will seek to invoke executive privilege against their testimony to protect the sanctity of private White House conversations.

"Clearly to me any president would ask for executive privilege regarding these witnesses,” Graham said, adding that if they were that important to the House case against Trump, Democrats should have sought their testimony during the House investigation.

Democrats did seek more testimony from White House aides, but Trump ordered them to not cooperate with the impeachment investigation; several aides complied with Trump’s edict while others did not. Democrats dropped their efforts to compel some testimony out of a fear that it would result in a lengthy legal battle that could have been tied up in U.S. for months.

Trump is spending the weekend at his Mar-a-Lago retreat along the Atlantic Ocean in Florida. Late Saturday, he resumed his almost daily attacks on the Democrats' impeachment campaign against him, saying on Twitter, "What a disgrace this Impeachment Scam is for our great Country!" 

But Graham predicted that Trump would be exonerated ahead of the president’s annual State of the Union address set for Feb. 4.

"His mood is to go to the State of the Union with this behind him and talk about what he wants to do for the next, rest of 2020 and what he wants to do for the next four years," Graham said on Fox. "He is very much comfortable with the idea that this is going to turn out well for him."

Trump’s Senate impeachment trial is only the third such event in the nearly 2 1/2 centuries of U.S. history. Two other presidents — Andrew Johnson in the mid-19th century and Bill Clinton two decades ago — were impeached by the House but acquitted in Senate trials and remained in office. A fourth U.S. president, Richard Nixon in the mid-1970s, faced almost certain impeachment in the Watergate political scandal, but resigned before the House acted.