The White House's top Ukraine expert is due to testify before impeachment investigators Tuesday—and his testimony is expected to be some of the most damaging for President Trump so far. According to prepared testimony seen by Politico, Army Lt. Col. Alexander Vindman, the first current White House official to testify, will tell House investigators that he believes Trump undermined national security by asking Ukraine's president to investigate the Bidens. Vindman, a decorated Iraq veteran who serves on the National Security Council, plans to say that he twice reported concerns about Trump's Ukraine policy to the NSC's lead counsel. "I did not think it was proper to demand that a foreign government investigate a US citizen, and I was worried about the implications for the US government’s support of Ukraine," his testimony states.
Vindman, who said he registered his objections out of a "sense of duty," will be the first official to testify who was on the line during Trump's July 25 phone call with Volodymyr Zelensky, the New York Times reports. In his prepared testimony, he states that he realized that if Ukraine investigated the Bidens, "it would likely be interpreted as a partisan play which would undoubtedly result in Ukraine losing the bipartisan support it has thus far maintained." He states that he reported both the phone call and a July 10 meeting in which US Ambassador to the EU Gordon Sondland spoke about "delivering specific investigations" in order to secure a meeting between Trump and Zelensky. The AP reports that Vindman will also testify that he is not the whistleblower and does not know the whistleblower's identity. (Read more Trump impeachment stories.)