Transcript for What to watch as public impeachment hearings begin
speculation about that. To capitol hill now where the first public hearings on impeachment set for Wednesday starting with William Taylor, the top U.S. Diplomat in Ukraine and George kept, the deputy assistant secretary of state followed by the fired U.S. Ambassador to Ukraine, Marie yovanovitch on Friday all expected to detail an improper pressure campaign by president trump as Republicans release a list of witnesses they want to call. Our senior congressional correspondent Mary Bruce tracking it all on capitol hill. Good morning, Mary. Reporter: Good morning, George. Well, as this impeachment inquiry enters the next phase this is all about making a public case. Democrats with these hearings are looking to focus squarely on the president's actions to pressure Ukraine while Republicans are now looking to broaden the scope of these hearings. As capitol hill braces for public impeachment hearings this morning, fresh fights over who should testify. Well, I never even heard of some of these people. I don't know who they are. Reporter: On Wednesday, that first witness to come before camera, the top U.S. Diplomat in Ukraine, bill Taylor. In explosive closed door testimony, Taylor implicated the president in a campaign to pressure Ukraine saying it was his, quote, clear understanding that Ukraine would not souvenirly $400 million in critical military aid until they agreed to investigate trump's political rivals. This is a very strong case of bribery. The constitution's very clear. Treason, bribery or acts of omission, and in this case, it is clearly one of those. Reporter: Shifting tactic, some Republicans are now condemning trump's behavior but say it doesn't rise to the level of impeachment. I believe it was inappropriate. I do not believe it was Reporter: But trump is not on board with that defense tweeting, Republicans don't be led into the fool's trap of saying it was not perfect but is not impeachable insisting nothing was done wrong and Republicans put out their own wish list including Joe Biden and his son Hupp and the anonymous whistle-blower who sparked this inquiry. It's impossible to bring this case forward in my view fairly without us knowing who the whistle-blower is and having a chance to cross-examine them about any buy glass they may have. Reporter: But Democrats say that's not going to happen. The chairman leading the hearings, Adam Schiff, says it would be redundant and would only place their personal safety at grafk risk eager to focus on trump Democrats are not likely to call hunter Biden either. Schiff warning they will not serve as seeking for any member to carry out the shame sham investigation into the Bidens. House investigators are still hoping to hear from two witnesses with firsthand knowledge, former national security adviser John Bolton and acting white house chief of stave Mick Mulvaney. The white house is trying to block them from appearing. Bolton seems willing to talk but is looking for the courts to decide whether he can comply and, George, in a surprise twist Mick Mulvaney is now also looking to the courts to decide his next move here. Yeah, the question is how long that would take. Meantime, Mary, that ukrainian-american working with Rudy Giuliani indicted for some campaign finance violations now appears eager to testify against Giuliani and president trump. Reporter: Yeah, George, lev parnas is now willing to speak with congressional investigators and comply with a subpoena and this morning "The New York Times" is previewing why he would be such a critical witness. His lawyer telling "The times" that he plans to tell house investigators he personally told Ukrainian officials they needed to launch an investigation into the Bidens or else they would not receive millions in that critical military aid, George. That is exactly the kind of ultimatum the white house and the president have been denying. Okay, Mary, thanks very much. I know you'll join our live coverage of the first hearings that starts 10:00 eastern right here on ABC and ABC news live. Folks will be watching. Overseas to chaos erupting
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