rarrarorro/iStock(WASHINGTON) — President Donald Trump’s impeachment defense team on Tuesday heads into their final day of opening arguments as questions over whether senators will hear new witnesses at the trial remain up in the air.

Trump’s lawyers are expected to finish making their case on the Senate floor by late afternoon.

The next phase of the trial — where senators will submit questions to both sides for up to 16 hours — is expected to begin Wednesday, according to White House sources and Senate aides. After that, a key point in the trial — a Senate vote on whether to consider new witnesses and other evidence — could come as early as Friday.

Republicans faced new pressure to add witnesses following newly reported revelations from the New York Times that former National Security Adviser John Bolton claims Trump told him he wanted help from Ukraine to investigate Democrats and would withhold their military aid to get cooperation.

But in a twist late Monday, Oklahoma Republican James Lankford suggested that senators could review the unpublished manuscript of Bolton’s forthcoming book. In a video posted to Facebook Monday, after Republicans spent the day largely dodging questions of whether to accept new witnesses, Lankford called Bolton’s information “pertinent” to the trial.

“If John Bolton’s got something to say, there’s plenty of microphones all over the country that he should step forward and start talking about it right now,” Lankford said.

Sen. Lindsey Graham, a staunch ally of President Trump, said he agrees that the draft manuscript of Bolton’s forthcoming book be made available to senators, but in a classified setting.

Bolton’s book is set for publication in March and his representatives have said the draft manuscript does not contain classified information.

As the Trump team delivered arguments Monday, they unfolded two separate strategies for the senators to consider. While the president’s primary defense lawyers continued to insist the facts didn’t support charges from House Democrats, the day concluded with former Harvard Law School professor Alan Dershowitz arguing the articles of impeachment themselves were unconstitutional — even if Trump had done exactly what the articles allege.

“Even if criminal conduct were not required, the framers of our Constitution implicitly rejected — and if it had been presented to them would have explicitly rejected — such vague terms as abuse of power and obstruction of Congress as among the enumerated and defined criteria for impeaching a president,” Dershowitz argued Monday evening, saying the Constitution requires criminal conduct or something close to it.

The newly reported revelations from the New York Times that Trump told his former National Security Adviser John Bolton he wanted help from Ukraine to investigate Democrats and would withhold their military aid to get cooperation largely went unaddressed by the president’s defenders until Dershowitz took the floor.

“Nothing in the Bolton revelations, even if true, would rise to the level of an abuse of power or an impeachable offense, that is clear from the history that is clear from the language of the Constitution,” Dershowitz said.

Here is how the day is unfolding. Please refresh for updates.

11:13 Schumer says Bolton must testify so senators can decide whether he or Trump is telling the truth

Senate Minority Leader Chuck Schumer makes another argument for witnesses before Trump’s impeachment trial convenes at 1 p.m.

He notes that with the president’s denial of John Bolton’s allegation on Monday, the two are telling opposing stories and says, since Trump won’t testify, senators need to hear from Bolton to decide who’s telling the truth.

He says it’s “on the shoulders of four Republican senators” to make sure Bolton, acting White House Chief of Staff Mick Mulvaney and two other administration officials testify, referring to GOP Sens. Mitt Romney, Susan Collins, Lisa Murkowski and Lamar Alexander.

He also called the GOP talk of having senators read the Bolton manuscript in a secure setting is an “absurd proposal.”

“Nothing is a substitute for a witness testifying under oath,” Schumer says.

“We’re not bargaining with them,” Schumer says of Republican talk of having Hunter Biden testify in exchange for Bolton appearing. “Our goal is to get the truth, plain and simple.”

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