In a Fox News interview Sunday morning, Ted Cruz said Democrats were “terrified” of hearing testimony from Hunter Biden.

Whether witnesses appear in the Senate trial has been a point of tension among Democrats and Republicans following last month’s House vote to impeach President Trump, though some Republicans have said they want witnesses to appear.

Cruz has called for a rule of reciprocity if witnesses are allowed, meaning the defense could call a witness for every witness called by the prosecution.

Four Senate Republicans need to join Democrats in order to allow witnesses in the impeachment trial.

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Sen. Ted Cruz, a Republican from Texas, said Sunday that Democrats were “terrified” of hearing testimony from Hunter Biden, the son of former Vice President Joe Biden, as part of President Donald Trump’s impending impeachment trial in the Senate.

Cruz made the comments on an appearance on Fox News’ Mario Bartiromo “Sunday Morning Futures,” The Hill reported. The 2016 Republican presidential candidate told Bartiromo that rules of reciprocity should apply in the impeachment trial, meaning if the prosecution gets to call a new witness, the defense should get to call one, too.

“If the prosecution gets a witness, the defense gets a witness,” Cruz said. “If the prosecution gets two, the defense gets two. If the prosecution gets to call John Bolton, the prosecution gets to call Hunter Biden. The Democrats are terrified about seeing a witness like Hunter Biden testify because they don’t want to hear evidence of actual corruption.”

Cruz first proposed the reciprocity rule on January 14, according to Fox News. The idea garnered support from several Republicans, including Senate Majority Leader Mitch McConnell. The president’s son, Donald Trump Jr., also shared his support for the Cruz proposal.

Cruz said that Democrats had blocked “blocked all those witnesses in the House,” but said should Democrats continue their push to allow witnesses as part of the Senate trial, they will not be able to block them from testifying in the Senate phase of the process, which will determine whether the presidents actions with Ukraine warrant his removal from office.

Democrats and Republicans have clashed over whether to allow new witnesses to be interviewed by the Senate as part of the president’s impeachment trial. Lindsay Graham, a Republican from South Carolina and the chairman of the Senate Judiciary Committee, has also said that the rules of reciprocity should apply in the impeachment trial, The Hill said.

In an unprecedented and risky move, House Speaker Nancy Pelosi had waited weeks following the House’s December 18 decision to impeach the president to send the articles of impeachment to the Senate to trigger the trial. Pelosi waited amid disagreements over how to conduct the trial following Senate Majority Leader Mitch McConnell’s – and other Republican Senator’s – implication that the Senate trial would be conducted in tandem with the White House.

Comments from Republicans like Graham, who in December said he was not expecting to act as a “fair juror” in the Senate trial, further influenced Pelosi to hold the articles.

The House passed a resolution to send the articles to the Senate last week – on January 15 – after she said Senate Majority Leader Mitch McConnell, a Republican from Kentucky, had compromised and said the Senate would determine whether to allow witnesses in the trial. While Republicans viewed this as a loss for Pelosi and Democrats, a timeline of events shows that Pelosi’s decision to hold off on sending the articles might have paid off for the House speaker.

According to a report from The New York Times, Senate Democrats only need to convince four Republican senators to allow them to subpoena witnesses in the impeachment trial. Sens. Mitt Romney of Utah, Susan Collins of Maine, and Lisa Murkowski of Alaska have already said they might be open to witnesses in the trial, meaning Democrats need to find just one more Republican senator.

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