Joe Scarborough bashes Senate GOP: Voters will hold them accountable for 'rigging' impeachment trial

Senate Republicans are making a costly mistake by blocking additional witnesses from testifying in President Trump's impeachment trial, MSNBC host Joe Scarborough argued Friday, predicting the move will hurt the president's chances for re-election.

"They will be stuck with this vote forever, as they go down in defeat in the fall and yes, you're right, when their obituaries are one day written," Scarborough said, addressing morning show regular Donny Deutsch.

The "Morning Joe" panel was reacting to key swing-vote Sen. Lamar Alexander, R-Tenn., coming out against additional witnesses in the impeachment trial. His announcement means that a call for additional testimony, including from former national security adviser John Bolton, will likely be voted down by the Republican-controlled Senate.

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The blocking of witnesses paves the way for Trump's acquittal, possibly as soon as Friday night, though multiple congressional sources told Fox News that Senate Minority Leader Chuck Schumer, D-N.Y., could seek to have the trial spill over into next week by introducing a series of motions and calling for more debate.

“The Senate can only move as fast as its slowest member," said one source. Asked when the trial would end, another replied, “when everyone is exhausted.”

Scarborough predicted that even if Bolton and other witnesses do not testify, damning information will still come out about the "drug deal" involving Trump and Ukraine.

"After that information gets out, other people are going to come forward," he said, referencing the release of Bolton's book in which he reportedly claims that Trump explicitly linked a hold on Ukraine aid to an investigation of Joe and Hunter Biden.

“And every one of these Republicans are going to be held accountable for them obstructing justice, obstructing a fair hearing by obstructing the calling of additional witnesses like John Bolton, who knows exactly what happened. They will be the people who will be seen rigging this trial, and it’s just gonna hurt them," Scarborough said.

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"The American people are going to have a complete view of just how ugly this drug deal was by the time November rolls around, and just how guilty the President of the United States was, and just how much he put his own personal interest ahead of the interest of America’s national security," he continued.

Should the witness vote fail as expected on Friday evening, the Senate would likely then vote on either additional motions for debate, or even the articles of impeachment themselves. If the witness vote unexpectedly succeeds, it would likely extend the length of the trial significantly, and lead to extended debate over which witnesses to call.

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When the final votes on the articles occurs, an extraordinarily unlikely two-thirds supermajority vote is needed to convict and remove Trump.

Fox News’ Gregg Re contributed to this report.