Top Democrats say Giuliani's Ukraine trip is "a crime in progress"

House Intelligence Chairman Adam Schiff (D-Calif.) and Judiciary Chairman Jerry Nadler (D-N.Y.) said on ABC's "This Week" that Rudy Giuliani's recent trip to Ukraine to dig up more dirt on the Bidens is "a crime in progress," claiming that it underscores the argument that President Trump's conduct poses an ongoing "threat to election integrity."

What they're saying:

• Schiff: "This misconduct goes on. The threat to our election's integrity coming up goes on. It's a clear and present danger, I think, to our democracy and not something we can turn away from simply because the Republicans in the House refuse to do their duty and continue to put the person of the president above their constitutional obligation."
• Nadler: "This is a crime in progress against the Constitution and against American democracy. We cannot take the risk that the next election will be corrupted through foreign interference solicited by the president, which he's clearly trying to do."

Context: Giuliani in early December traveled to Ukraine and Hungary to meet with former Ukrainian prosecutors to gain information that he hoped would undercut the case for impeachment. After returning, Giuliani claimed that Trump asked him to brief the Justice Department and GOP senators on his findings.

• Senate Judiciary Chairman Lindsey Graham (R-S.C.) has said he would be open to hearing from Giuliani after impeachment has concluded, but it's not yet known if Republicans plan to call the president's lawyer to testify in the Senate trial.

The big picture: Senate Majority Leader Mitch McConnell has vowed "total coordination" with the White House during the impeachment trial, while Graham has said he is not trying to hide the fact that he has already made up his mind. The comments have set off outrage from Democrats.

• Nadler said on ABC: "Here you have the majority leader of the Senate, in effect the foreman of the jury, saying he's going to work hand-in-glove with the defense attorney. Now that's a violation of the oath they're about to take, and it's a complete subversion of the constitutional scheme."

Of note: Senators must take the following oath before sitting in impeachment trials, according to Senate impeachment rules:

"I solemnly swear (or affirm, as the case may be,) that in all things appertaining to the trial of the impeachment of [name of person being impeached], now pending, I will do impartial justice according to the Constitution and laws: so help me God."

Go deeper: Giuliani pursued business in Ukraine while seeking to dig up dirt on Trump's rivals