Lindsey Graham threatens Democrats: If you call even one witness for impeachment trial, we’ll open up 'Pandora's box'

Republican Sen. Lindsey Graham (S.C.) warned Democratic colleagues Monday night that if they decide to call even one witness in the Senate's upcoming impeachment trial against former President Trump, they'll be opening up "Pandora's Box."

Last month, the Democrat-controlled House voted to impeach Trump a second time for "incitement of insurrection" after a mob of his supporters stormed the U.S. Capitol on Jan. 6 while Congress was in session. The process has now moved to the Senate, where a trial is set to begin next week.

Graham, the outgoing chairman of the Senate Judiciary Committee, expressed that he looks forward to a speedy trial and acquittal of Trump. But he noted that should Democrats choose to turn it into a "political commercial" and prolong the business for "weeks and months" by calling witnesses, Republicans are prepared to play ball by calling the FBI to testify about security failures at the U.S. Capitol.

"If you open up that can of worms [by calling witnesses], we'll want the FBI to come in and tell us about how people actually pre-planned these attacks and what happened with the security footprint at the Capitol," Graham said.

"You open up Pandora's box if you call one witness," he continued. "I hope we don't call any and we vote and get this trial over next week when it starts."

With the trial's Feb. 9 start date looming, Reuters reported Monday that the House Democrats in charge of impeachment proceedings in the Senate are expected to announce whether or not they will call witnesses by as early as Tuesday.

Democrats are expected to face an uphill climb toward a conviction, especially after 45 of the GOP's 50 senators voted in a procedural motion to object to impeachment proceedings last week, leading Sen. Rand Paul (R-Ky.) to call the prospect "dead on arrival." Democrats would need at least 17 GOP senators to declare Trump guilty in order to garner the two-thirds vote required to convict.

Nevertheless, Trump, for his part, is currently assembling a legal defense and preparing a formal response to the charges. A conviction in the Senate will mean rather little, politically, since Trump has already exited office. However, a vote to impeach could open the potential for a vote to bar him from seeking public office in the future.