Democratic Sen. Sherrod Brown 'fine' with Hunter Biden testifying in Trump impeachment trial

As the Senate prepares for the impeachment trial of President Donald Trump, one Democratic senator says he is open to former Vice President Joe Biden's son, Hunter, testifying if that is what it takes to have new witnesses called. 

"Fine," Sen. Sherrod Brown said Sunday on CNN's "State of the Union" when asked if he was prepared for Hunter Biden to testify. "I understand both sides get to call witnesses." 

It remains an open question whether new witnesses can be called in the trial that will determine whether Trump remains in office after being impeached in the Democratic-controlled House on charges of abuse of power and obstruction of Congress. 

House Speaker Nancy Pelosi, D-Calif., delayed sending the articles of impeachment to the Senate to try to get Senate Majority Leader Mitch McConnell to commit to a "fair" trial, which she said would have to include relevant new witnesses and evidence. McConnell refused to make any commitment and said the Senate would independently determine how it proceeds.

Senate Minority Leader Chuck Schumer, D-N.Y., has said there are four witnesses Democrats would still like to hear from, including acting White House Chief of Staff Mick Mulvaney and former national security adviser John Bolton, who said he would testify if subpoenaed by the Senate.

Several Republicans who oppose new witnesses say House Democrats rushed the process and should have subpoenaed the witnesses during the inquiry, while others say they are open to more testimony. 

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Sen. Ted Cruz, R-Texas, has said if new witnesses are called, there should be "reciprocity." 

"That means, if the prosecution gets a witness, the defense gets a witness," Cruz said Sunday on Fox News. "That means, if the prosecution gets to call John Bolton, then the president gets to call Hunter Biden." 

Cruz said he believes Democrats are "terrified" of Hunter Biden's testimony "because they don't want to hear evidence of actual corruption" that "occurred during the Obama administration." 

But Brown said some Senate Republicans have told him in private they see the call to have the former vice president's son testify as a "distraction." 

"I don't know what Hunter Biden has to do with the phone call that was made," Brown said, referring to a July 25 conversation between Trump and Ukrainian President Volodymyr Zelensky.

"The point is, we need witnesses," Brown said. "I don't understand how you can – to the American public – make the case that this is a real trial if there are no witnesses and there is no new evidence."

Trump is accused of using military aid to pressure Ukraine into opening two investigations he thought could benefit him politically: One into a conspiracy theory alleging Ukraine, not Russia, interfered in the 2016 election, and the other into Biden's role in his son's appointment to the executive board of Burisma, a Ukrainian natural gas company. 

Though officials in the U.S. and Ukraine previously said they found no evidence of wrongdoing, Trump and his supporters have accused the former vice president of corruption in connection to his son's lucrative seat on Burisma's board.

The president said he wanted Ukraine to look into the matter strictly because he wished to combat corruption. Democrats say he was trying to politically damage Biden, who is a top candidate in the Democratic primary. 

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Democrats are particularly eager to hear from Bolton because officials testified in the House inquiry that he was opposed to leveraging military aid to pressure Ukraine and disparaged the effort as a "drug deal."  

"Any Republican senator who says there should be no witnesses, or even that witnesses should be negotiated, is part of the cover-up," said House Judiciary Committee Chairman Jerry Nadler, D-N.Y., Sunday on CBS News' "Face the Nation." 

Nadler said testimony from Hunter Biden would be irrelevant because "he has no knowledge of the accusations against the president." He said Trump's supporters only want the former vice president's son to testify to "smear" the Bidens exactly how Trump hoped Ukraine would. 

Sen. John Cornyn, R-Texas, said on "Face the Nation" that the Senate will vote Tuesday on a resolution outlining how the trial will be conducted. He said it would mirror the format for the 1999 impeachment trial of President Bill Clinton by having both sides present their cases before deciding if additional testimony was needed. 

"We have a two-phase deal here like we did under the Clinton trial. First, we're going to hear from the managers and arguments on both sides and see what kind of case they have," said Sen. Richard Shelby, R-Ala., on "This Week." 

Sen. Dick Durbin, D-Ill., said on "Meet the Press" that Democrats don't know what McConnell will propose on Tuesday, but warned "the American people expect a real trial to have real witnesses and evidence." 

"The Senate itself is on trial, as far as I'm concerned, and the jury's the American people," Durbin said. "The question is whether or not we are going to have a fair trial, whether the members of the Senate are going to be loyal to the Constitution or loyal to the president."

Durbin said he thought Republicans were still debating among themselves whether calling Hunter Biden as a witness "is really in their best interest" or if it would be "more theater than it should be."  

Defense attorney Alan Dershowitz, who is part of Trump's legal team, said on "This Week" that calling witnesses "will delay the trial considerably." 

"The president will invoke executive privilege as to people like John Bolton. That will have to go to the court and we'll have to have a resolution of that before the trial continues," Dershowitz warned.