House to Hear From 8 Witnesses in Trump Impeachment Inquiry

The U.S. House of Representatives is holding its second week of public hearings on the impeachment inquiry into President Donald Trump with testimony by eight aides and officials, including the top diplomat to the European Union, Tuesday through Thursday.

Jennifer Williams, an aide to Vice President Mike Pence, and Lt. Col. Alexander Vindman, the National Security Council's top Ukraine expert, are set to testify Tuesday morning, followed by former U.S. Special Envoy to Ukraine Kurt Volker and another former NSC official Tim Morrison on Tuesday afternoon.

U.S. Ambassador to the EU Gordon Sondland is set to testify Wednesday morning, followed by career Pentagon official Laura Cooper and Undersecretary of State David Hale on Wednesday afternoon. Former White House adviser Fiona Hill is to testify Thursday.

All eight have testified previously in closed-door hearings about Trump's efforts to pressure Ukraine to investigate his political rival, former Vice President Joe Biden and his son, Hunter, who had served as a board member of a Ukraine natural gas company, and probe a discredited conspiracy theory regarding the 2016 president election. Three of the eight listened in on the July 25 phone conversation between Trump and Ukraine's president.

Democrats hope the hearings will sway public opinion in favor of impeachment. Republicans have used them to discredit the impeachment proceedings and poke holes in the witnesses' testimony.

Here is what you need to know about the eight witnesses and their role in the Ukraine affair.

Alexander Vindman

Alexander Vindman is a U.S. Army lieutenant colonel whose role as the National Security Council's top Ukraine expert at the White House has landed him in the national spotlight amid the impeachment investigation. Vindman listened in on a July 25 phone call between President Donald Trump and Ukrainian President Volodymyr Zelenskiy, which is at the center of the impeachment investigation. Vindman told impeachment investigators on Oct. 30 that he was so troubled by the call that he reported the president's comments to his superiors. Vindman, who was born in Ukraine in 1975, which was then part of the Soviet Union, was 3 years old when his family fled to the United States. He has served more than 20 years in the U.S. military.

Jennifer Williams

Jennifer Williams is a longtime State Department employee who is currently detailed to the office of Vice President Mike Pence as a senior adviser on European and Russian affairs. She is the first member of Pence's national security team to testify in the impeachment inquiry. Williams is one of two Pence staffers who listened in on the July 25 phone call between Trump and Zelenskiy. In September, Williams accompanied Pence to Warsaw, Poland, where he met with Zelenskiy and discussed the nearly $400 million in military assistance that had been put on hold by the White House.

Kurt Volker

Kurt Volker resigned as U.S. Special Envoy for Ukraine on Sept. 27, the day after he was subpoenaed to testify before House committees about his involvement in Trump's dealings with Ukraine. Along with Gordon Sondland, the U.S. ambassador to the EU, and Energy Secretary Rick Perry, Volker was one of the so-called "three amigos" who ran the Trump administration's Ukraine policy. Volker's more than 20-year career in public service began in 1986 when he was an analyst with the Central Intelligence Agency. When Arizona State University launched the McCain Institute for International Leadership in 2012, Volker was its first executive director, before stepping down last month.

Tim Morrison

Tim Morrison served as the senior director for European and Russian affairs on the National Security Council before he resigned last month. After graduating from Georgetown Law School, he spent 17 years working for former Arizona Republican Senator Jon Kyl and as a staffer with the House Armed Services Committee. Morrison was working on arms control and biodefense issues at the NSC when he was promoted to senior director of Russian affairs by then-Trump National Security Adviser John Bolton. In that capacity, Morrison would have intimate knowledge of issues in Ukraine and Russia. He also is one of seven known U.S. officials who listened in on the July phone call between Trump and his Ukrainian counterpart.

Gordon Sondland

FILE - Gordon Sondland, U.S. Ambassador to the European Union.

As Trump's ambassador to the European Union, Gordon Sondland was in frequent contact with Trump and other administration officials about Ukraine policy. On July 26, the day after Trump and Zelenskiy spoke by phone, Sondland and Trump had their own phone conversation during which the president was overheard asking whether Ukraine would "do the investigation" he had asked for. A wealthy hotel magnate, Sondland gave $1 million to Trump's 2017 inaugural committee. In March 2018, Trump picked him as his ambassador to the European Union. He was confirmed by the Senate in July.

Laura Cooper

Laura Cooper is a career Pentagon official responsible for policy on Russia, Ukraine and other nations in that region. Cooper first joined the Department of Defense in 2001. She held a series of posts at the Pentagon before being named the deputy assistant secretary of defense for Russia, Ukraine and Eurasia. In that capacity, she met with Volker in late August to discuss the frozen Ukrainian aid and was told by Volker that the hold might be lifted if Ukraine was willing to issue a statement disavowing election interference and vowing to prosecute anyone engaged in interference. Cooper later told impeachment investigators that she and others had expressed concerns about the legality of withholding congressionally authorized funds for Ukraine.

David Hale

As under secretary of state for Political Affairs, David Hale is the State Department's No. 3 official, a position to which Trump named him in 2018. A graduate of Georgetown University's School of Foreign Service, Hale joined the foreign service in 1984 and holds the rank of career ambassador. In early March, he traveled to Ukraine where he asked then-Ambassador Marie Yovanovich to extend her diplomatic term by one year and stay in the country through 2020. Later, when Rudy Giuliani, the president's point man on Ukraine, launched a smear campaign to oust Yovanovitch, Hale instructed a subordinate, George Kent, to "keep [your] head down." Hale testified behind closed doors this month about the State Department's handling of the former ambassador's recall.

Fiona Hill

A British-born American foreign affairs expert, Fiona Hill served as the National Security Council's top Russia expert until June. The first former White House official to testify in the House impeachment inquiry, Hill told investigators in October that Yovanovitch's removal was the "result of the campaign that Mr. Giuliani had set in motion" and that she had personally been the target of similar smear campaigns. Hill also testified about a July 10 White House meeting between U.S. and Ukrainian officials at which Sondland announced that "we have an agreement with the chief of staff for a meeting (between Trump and Zelenskiy) if these investigations in the energy sector start."