President Donald Trump is on trial in the Senate after being impeached by the Democratic-controlled House over asking the newly elected Ukrainian president to investigate one of his chief political rivals, former Vice President Joe Biden. Biden led the Obama administration's diplomacy in Ukraine while his son, Hunter, was on the board of directors of a gas company.
Trump says his own behavior was appropriate. His critics say he had withheld military aid to Ukraine while he pressured its president, Volodymyr Zelenskiy, on the Bidens. A whistleblower's complaint accused Trump of "using the power of his office to solicit interference from a foreign country in the 2020 U.S. election." It further alleges that the White House engaged in a cover-up by hiding a transcript of the conversation on a computer server meant only for highly classified information.
With the Senate trial officially underway, here are some of the affair's main characters as fast-moving developments unfold.
Who's Who in the Trump-Ukraine Affair
President Donald Trump faces a formal impeachment inquiry led in the Democratic-controlled House after he asked the newly elected Ukrainian president to investigate one of his chief political rivals, former Vice President Joe Biden.
Credit: Noreen O'Donnell, Nelson Hsu, Nina Lin/NBC