Pence aide's testimony could address 'a ton of questions' about VP's role in Ukraine quid pro quo: CNN

On Wednesday, Jennifer Williams, an aide to Vice President Mike Pence, said that she will testify before House impeachment investigators if she receives a subpoena to do so.

On CNN's "OutFront," reporter Kaitlan Collins said that such testimony could be highly informative.

"Jennifer Williams will be interesting if she does show up tomorrow, as we've been expecting so far, because she is not a political appointee," said Collins. "She's not someone Pence selected necessarily to be on the staff. She's a State Department career official who was detailed to the vice president's office and has been there for several months and seen as a career official and not someone who would work inside the West Wing."

"But she's also notable because of what she knows," added Collins. "She was on that July call with the president and the president of Ukraine, and that call that is at the center of all of this. The questions are about what she heard. We are told by sources that she was concerned about what she heard, and it is not clear, and we do not believe, that she registered those complaints with anyone higher up than here, and we'll hear about that tomorrow. And she went on that trip with the vice president where he subbed in for President Trump because he was staying back at the White House to monitor an impending hurricane, and on that trip to Poland, that's where the vice president sat down with the Ukrainian leader."

"Pence has faced a ton of questions about his own role in this, including his own role about what he said to President Zelensky in Poland and whether or not he brought up the Bidens, something he said didn't come up, and there are questions about what the president said to him," said Collins. "That is why Jennifer Williams going up to the Hill tomorrow, if she does, and if she is subpoenaed, which right now we are likely expecting, will be something noteworthy here."

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