Military assistance for Ukraine was frozen by the White House for a period of weeks this summer, then released. Ukraine's president, however, never made the public commitment for investigations that intermediaries have said they sought on Trump's behalf.

Risk seen to U.S. diplomacy

Yovanovitch warned Congress on Friday that the precedent set by her recall from Ukraine weakened Washington's ability to work with developing nations around the world.

The U.S. has set an example for countries seeking to build institutions and fight corruption, Yovanovitch said — but her ouster showed that enemies in Ukraine could exploit American officials to get rid of someone they disliked.

"How could our system fail like this? How is it that foreign corrupt interests could manipulate our government?" she asked.

Yovanovitch acknowledged that Trump has the power to appoint and remove diplomats as he pleases, but she argued that if an American representative can be "kneecapped" for political reasons, it dilutes U.S. power.

"Shady interests the world over have learned how little it takes to remove an American ambassador who does not give them what they want," Yovanovitch said.

Yovanovitch already has talked with investigators; read her closed-door deposition here. Her opening statement Friday is available here.

"I saw it as a threat"

Although some State Department officials have said they objected to what they saw happening, Secretary of State Mike Pompeo agreed to end Yovanovitch's tenure early and spurned requests to defend her in public, witnesses have said.

Pompeo's adviser, Michael McKinley, faulted what he called Pompeo's willingness to sell out a career diplomat and resigned.

Yovanovitch said Friday that she lamented that Pompeo has declined to acknowledge that attacks on the foreign service are "dangerously wrong" and impair America's ability to work its will overseas.

She also was asked what she made of the account released by the White House in which Trump is described as telling Ukraine's president that "things were going to happen to her."

"I saw it as a threat," Yovanovitch said.

Can't see the video? Click here.

Case for the defense

Republicans emphasized Yovanovitch's tangential involvement in the central narrative and repeated that Trump has broad powers to replace any ambassador — and many other officials — within the administration.

Intelligence Committee ranking member Rep. Devin Nunes, R-Calif., underscored that Yovanovitch hasn't spoken to Trump, acting White House chief of staff Mick Mulvaney or other people central to the Ukraine affair.

Nunes said he didn't have many questions and he asked, rhetorically, why Yovanovitch was even before the committee. These impeachment proceedings are about pure political animus toward Trump, he said.

Nunes mocked Democrats' desire to "fulfill their Watergate fantasies" and called the first hearing, on Wednesday, a "farce" based on hearsay and "rumors."

Mulvaney earlier argued that the impeachment case boils down to complaints by the foreign policy establishment about Trump.

But the administration works for the president, foreign policy is necessarily political, and, Mulvaney said, critics need to "get over it."

Republican counsel Steve Castor also underscored with Yovanovitch, as he did with earlier witnesses, that corruption in Ukraine remains a real problem and that at least one big case involving the gas company Burisma hadn't been resolved.

That company added to its board the son of then-Vice President Biden; Trump sought an investigation into the Biden family, and his defenders have sought to draw attention to that aspect of the story.

The Bidens haven't been accused of breaking the law, but Trump and others continue to raise questions about Hunter Biden's payments by the Ukrainian company.

Rep. John Ratcliffe, R-Texas, asked Yovanovitch whether she agreed that Hunter Biden's tenure on the Ukrainian company's board might have created the appearance of a conflict of interest; she said she thought it may have.

Afternoon deposition

Also Friday, investigators were to hear behind closed doors from foreign service official David Holmes, a comparative newcomer in the Ukraine drama who could prove an important witness.

Holmes is understood to have been with a top diplomat, Ambassador Gordon Sondland, at a restaurant when Sondland got a call from Trump on his cellphone.

Holmes overheard Trump on that call ask Sondland about investigations he expected from Ukraine, according to testimony on Wednesday by another diplomat, Ambassador William Taylor.

Investigators want to hear from Holmes directly, and another question in the Ukraine affair is whether he might appear and tell his story in a public hearing.

The Associated Press reported that a second State Department staffer also was with Holmes and Sondland on the day of Trump's call, but details about that hadn't been confirmed by the Intelligence Committee and it wasn't clear when or if investigators might hear from that person — or when the public might.

White House correspondent Ayesha Rascoe contributed to this report.

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