Former special envoy to Ukraine Kurt Volker was the first State Department official to appear before three House committees heading the impeachment inquiry against President Donald Trump on Thursday.

Following Volker’s nearly 10-hour interview, the committees released dozens of text messages between U.S. diplomats in Ukraine discussing how to handle a response to Trump’s demands that the country launch an investigation into Joe Biden’s family.

In the texts, Volker and two other diplomats discuss how to navigate Trump’s requests for the probe into his political rival.

In one exchange, Volker and Ambassador Gordon Sondland discussed a draft statement in which the Ukraine government would announce an investigation into the 2016 U.S. presidential election and into a company whose board Biden’s son served on.

Volker is only the first of five State Department officials expected to testify before the committees. Here’s what we know about each official—and their role in the impeachment investigation.

Kurt Volker, former special envoy to the Ukraine, exits after a closed-door deposition before House committees on Capitol Hill in Washington, D.C., U.S., on Thursday, Oct. 3, 2019. Volker, who stepped down last week from his unpaid role representing American interests in Ukraine, will give a deposition to the three House committees looking into President Donald Trump’s pressure on a foreign power to investigate a political rival, Joe Biden. Photographer: Sarah Silbiger/Bloomberg via Getty Images Sarah Silbiger/Bloomberg via Getty Images

1. Kurt Volker

Volker is a career diplomat who previously served as U.S. ambassador to NATO in 2008 under President George W. Bush. In the years following, he became the executive director of the McCain Institute at Arizona State University, a position he still holds.

In July of 2017, however, then-Secretary of State Rex Tillerson appointed Volker U.S. special representative for Ukraine relations, a role he took on in a part-time, volunteer capacity. Volker resigned from his role on September 27th without explanation.

According to the whistleblower complaint, Volker met with Ukrainian Volodymyr President Zelensky on July 26, a day after that president’s call with President Trump. The complaint suggests that Volker “provided advice to the Ukrainian leadership about how to ‘navigate’ the demands that the President had made of Mr. Zelensky.”

U.S. Ambassador to Ukraine Marie Yovanovitch during a meeting with Prime Minister of Ukraine Volodymyr Groysman Kyiv, Ukraine, November 12, 2018 (Photo by Maxym Marusenko/NurPhoto via Getty Images) Maxym Marusenko—NurPhoto via Getty Images)

2. Marie Yovanovitch

Yovanovitch is a career foreign service officer, who has served in a number of assignments over her three-decade career, including as Ambassador to Armenia and Kyrgyzstan. Most recently, she served as U.S. ambassador to Ukraine from 2016 until she was recalled in May of this year, ending her post two months early. She is currently a State Department fellow at Georgetown University.

Yovanovitch’s abrupt May departure came after being accused in some right-wing circles of having anti-Trump bias. The whistleblower contends in their complaint that Yovanovitch was removed because she had criticized Ukraine’s Prosecutor General, Yuriy Lutsenko’s corruption record. The complaint further notes that Trump’s personal attorney, Rudy Giuliani, told a Ukrainian journalist in May that she was removed because “she was part of the efforts against the President.”

In the memo detailing Trump’s July 25 call with Zelensky, he referred to Yovanovitch as “bad news,” adding that “the people she was dealing with in the Ukraine were bad news.”

3. George Kent

George Kent is also a career foreign service officer, who currently serves as deputy assistant secretary in the European and Eurasian Bureau at the State Department.

From 2015 to 2018 he was the deputy chief of mission at the U.S. embassy in Ukraine, serving under Yovanovitch for much of that time.

Gordon Sondland, the United States Ambassador to the European Union, adresses the media during a press conference at the US Embassy to Romania in Bucharest September 5, 2019. (Photo by Daniel Mihailescu/AFP/Getty Images) DANIEL MIHAILESCU—AFP/Getty Images

4. Gordon Sondland

Trump appointed Gordon Sondland to be U.S. Ambassador to the European Union in 2018. Sondland is a Republican donor and political appointee without prior diplomatic experience. A multimillionaire hotelier, Sondland is the founder and CEO of Provenance Hotels.

According to the whistleblower complaint, Sondland was also present during Volker’s July meeting with Zelensky, and also “sought to help Ukrainian leaders understand and respond to the differing messages they were receiving from official U.S. channels on the one hand, and Mr. Giuliani on the other.”

5. T. Ulrich Brechbuhl

Secretary of State Mike Pompeo appointed his former classmate T. Ulrich Brechbuhl to be State Department Counselor in spring 2018. According to his official bio, Brechbuhl “provides strategic guidance to the Secretary on foreign policy, undertakes efforts to enhance U.S. diplomacy and public outreach, and conducts special diplomatic assignments as directed by the Secretary.”

The whistleblower’s complaint lists Brechbuhl among those who listened to Trump’s July call with Zelensky. Brechbuhl was also reportedly a guest at a dinner hosted by Sondland, at which Zelensky was also present.

—With The Associated Press

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