The 5 impeachment witnesses who locked down the Democrats' case against Trump

• Five days of impeachment inquiry hearings, held over the past two weeks, concluded Thursday.
• The public heard from 12 people who testified about President Donald Trump's efforts to strongarm a critical ally into delivering political dirt while holding up vital military aid and a White House meeting.
• But five witnesses stood out in their ability to speak to every facet of what some have dubbed "Ukrainegate": the phone call, cover-up, quid pro quo, and smear campaign against a career diplomat.
• Those officials are Lt. Col. Alexander Vindman, the top Ukraine expert on the National Security Council; Bill Taylor, the US's chief envoy in Ukraine; Gordon Sondland, the US's ambassador to the EU; Laura Cooper, a deputy secretary at the Defense Department; and Marie Yovanovitch, the US's former ambassador to Ukraine.
• Scroll down to read how each official offered groundbreaking testimony in the impeachment inquiry confirming every aspect of the Ukraine scandal.
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Five days of impeachment inquiry hearings, held over the past two weeks, concluded Thursday.

The public heard from 12 people who testified about President Donald Trump's efforts to strongarm a critical ally into delivering political dirt while holding up vital military aid and a White House meeting.

House Democrats called these witnesses forward to help them make the case in the impeachment inquiry that the president abused his power by using his public office for private gain.

The controversy at the heart of the investigation, dubbed "Ukrainegate" by some, broadly consists of four chapters:

• The phone call on July 25 that Trump made to Ukrainian President Volodymyr Zelensky, in which he repeatedly pressured Zelensky to investigate former Vice President Joe Biden and his son, Hunter, over the latter's involvement with the Ukrainian natural gas company Burisma Holdings. Trump also asked Zelensky to investigate a bogus conspiracy theory suggesting it was Ukraine, not Russia, that meddled in the 2016 election.
• The cover-up, in which White House officials and lawyers scrambled to bury transcripts of the phone call on a top-secret codeword server because they feared they'd just witnessed the president commit a crime. Namely, asking a foreign power to interfere in domestic political affairs.
• The quid pro quo, which showed the phone call was just one data point in a months-long campaign to pressure Ukraine to publicly commit to the investigations while freezing military aid and holding up a White House meeting that Zelensky desperately wanted.
• The smear campaign against a widely respected US ambassador who was forced out and publicly embarrassed because she refused to help the president and his allies in their shadow policy campaign with respect to Ukraine.

The dozen fact witnesses Congress heard from were able to speak to all of these in varying degrees.

But four nonpartisan career diplomats and national security officials and one Trump-allied ambassador, in particular, stood out in helping Democrats make their entire case against the president.

• Lt. Col. Alexander Vindman
  • Vindman is the top Ukraine expert on the National Security Council and a Purple Heart recipient. He directly listened in on Trump's July 25 phone call and described it to Congress as being "inappropriate" because it consisted of none of the foreign policy talking points Trump had been given and instead veered off into domestic political territory.
  • The military veteran also testified about the White House's subsequent efforts to cover up the details of the call. He said he informed the NSC's top lawyer, John Eisenberg, of what he'd heard on the call immediately after, and that Eisenberg told him not to relay a word about it to anyone else.
  • After the White House reconstructed a rough summary of the call, Vindman realized it contained significant omissions. Specifically, it left out one of Trump's mentions of former Vice President Joe Biden and corruption, and Zelensky's specific mention of Burisma Holdings. Vindman testified that he tried to correct the rough transcript to include those phrases, but they never made it in.

• Bill Taylor
  • Taylor is the US's ambassador to Ukraine, and he testified at length about the quid pro quo in which Trump tried to leverage US foreign policy for personal gain.
  • He offered a significant new detail that he didn't provide during his closed-door testimony. Specifically, Taylor revealed that a member of his staff overheard a phone call between Trump and Gordon Sondland, the US's ambassador to the EU, on July 26 in which Trump asked Sondland about the status of "the investigations." Sondland, according to Taylor, told Trump the Ukrainians were ready to move forward. After the call, Taylor's staffer asked Sondland what Trump thought of Ukraine, and Sondland said "Trump cares more about the investigations of Biden, which [Trump's lawyer Rudy Giuliani] was pressing for."
  • This detail is hugely significant for a few reasons. First, it undercuts Trump's claim that he "hardly know[s]" Sondland. Second, it shows Trump's personal involvement in the Ukraine pressure campaign.
  • Taylor also vividly detailed the divergence between the "regular" and "irregular" foreign policy channels with respect to Ukraine. The regular channel, which Taylor was a part of, consisted of routine foreign policy and diplomacy in the country, which is a critical US ally.
  • The irregular channel consisted of bullying Ukraine into acceding to Trump's demands. This channel, according to Taylor and other witnesses, was spearheaded by Giuliani, Sondland, the US's former Special Representative to Ukraine Kurt Volker, the acting White House chief of staff Mick Mulvaney, and the outgoing energy secretary Rick Perry.

• Gordon Sondland
  • Sondland was Trump's man in the middle of the Ukraine saga. A wealthy hotel magnate, Sondland was given the ambassadorship after donating $1 million to the president's inaugural committee.
  • His status as a Trump ally made it all the more devastating when he testified in no uncertain terms that the president engaged in a quid pro quo with Ukraine.
  • "Members of this Committee have frequently framed these complicated issues in the form of a simple question: Was there a 'quid pro quo?" Sondland said. "As I testified previously, with regard to the requested White House call and White House meeting, the answer is yes."
  • Sondland also testified that "everyone" was in the loop on Trump's pressure campaign. He threw top brass across the government - from the president, the vice president, Secretary of State Mike Pompeo, former national security adviser John Bolton, and more - under the bus in his groundbreaking testimony.

• Laura Cooper
  
  • Cooper is a deputy secretary at the Defense Department, and her testimony this week was some of the most explosive so far.
  • She revealed on the day of Trump's July 25 phone call, her staff got three separate inquiries asking about the status of Ukraine's military aid, which Trump had frozen just days before. Two of those came from Ukrainian officials, and one came from a congressional committee.
  • Cooper's testimony was monumental because it threw a wrench into Trump's main defense in the snowballing impeachment inquiry. Trump has said that Zelensky couldn't have felt pressured during their call and there was no quid pro quo because the Ukrainian president didn't even know the aid had been frozen when they spoke. Instead, Trump and his allies have said the Ukrainians only found out about the freeze in late August, when Politico first reported on it.
  • But the Pentagon official's testimony shows the Ukrainians were keenly aware of the aid freeze as early as July 25, which sheds a whole new light on the import of Trump's words to Zelensky, in which he asked him to "do us a favor, though," and investigate Burisma, the Bidens, and the 2016 election.

• Marie Yovanovitch
  • Yovanovitch was the US's ambassador to Ukraine until she was forced out in May. She gave riveting and at times emotional testimony last week describing the "smear campaign" that Trump and Giuliani carried out to engineer her removal.
  • The career diplomat testified that she was removed not for a legitimate cause, but because of "false allegations by people with clearly questionable motives."
  • She described being subjected to baseless attacks on her reputation, which she said were leveled against her because she refused to help Giuliani pressure the Ukrainians to turn over political dirt to help Trump's reelection campaign.
  • Yovanovitch also said she was "shocked" and "devastated" by what Trump said about her in his July 25 call with Zelensky. On the call, Trump mentioned Yovanovitch and said she was "bad news," adding that "she's going to go through some things."
  • Yovanovitch said a person who saw her reading the memo of the call said "the color drained from my face. I think I even had a physical reaction. Even now, words fail me."
  • Trump publicly attacked Yovanovitch while she testified. Yovanovitch said she found his comments "very intimidating."
  • The vast majority of the witnesses who testified in the impeachment inquiry forcefully defended Yovanovitch and praised her "professionalism," "dedication," and "decency," among other things. They testified that it was "shameful" the way she was removed following the smear campaign.

The other eight witnesses also testified to key moments throughout the last several months that illustrate Trump's and his allies' agenda to force Ukraine to cave to his demands.

David Holmes, Taylor's staffer who overheard the call, described his intense dismay at learning the aid to Ukraine was frozen and why. Fiona Hill, the NSC's former top Russia analyst, gave scathing testimony in which she said she refused to go along with the "fictional narrative" Trump was pushing about Ukrainian election interference.

George Kent, a senior State Department official, blew a hole through all of Trump's beliefs about the Bidens' corruption and Ukraine's purported election meddling.

Volker, State Department official David Hale, and former NSC official Tim Morrison, were on the GOP's witness list and their testimony ended up doing more to hurt the party's position than help it.

But as far as cementing the Democrats' case against Trump, the testimony of Vindman, Taylor, Sondland, Cooper, and Yovanovitch drove the story home.

• Read more of Insider's impeachment coverage:
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• Trump could be impeached and removed from office but still win reelection in 2020
• Over half of the House of Representatives support the impeachment inquiry against Trump - see all of them here
• Everything you need to know about Trump's impeachment process: What's happened, who the players are, and what comes next

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