Acting U.S. ambassador to the Ukraine Bill Taylor revealed behind closed doors on Tuesday that he was told President Donald Trump wanted military aid to Ukraine, contingent on a public declaration from President Volodymyr Zelensky to investigate the Bidens—illustrating that the work of the House impeachment investigation was still producing breathtaking revelations from officials that the State Department had directed not to testify.
Members who heard the statement further said they predicted officials who had already testified would return based on his testimony and more Trump officials could testify.
Collectively, the developments indicated that the inquiry was mushrooming, producing new information just a month into a fast-moving investigation, and not showing signs of wrapping up.
Taylor spoke to members Tuesday, giving an opening statement where he said in a phone call that Ambassador to the European Union Gordon Sondland told him that “President Trump had told him that he wants President [Volodymyr] Zelensky to state publicly that Ukraine will investigate Burisma and alleged Ukrainian interference in the 2016 election.”
Sondland further told him that “everything” was dependent on the announcement, including the security assistance. The statement undercut Trump’s denials of a quid pro quo, and, according to Taylor, that the pressure campaign came directly from the president.
Sondland testified before the committees last Thursday, but lawmakers indicated that he might need to come back after Taylor’s testimony.
“I think Gordon Sondland may very well have to come back,” said Rep. Gerry Connolly (D-Va.), a member of the House Committee on Oversight and House Foreign Affairs Committee, speaking after Taylor gave his opening statement behind closed doors.
“I walk away with the impression that Mr. Sondland is going to have some explaining to do,” said Rep. Raja Krishnamoorthi (D-Ill.), a member of the House Intelligence Committee. Rep. Stephen Lynch (D-Mass.) said his testimony “may cause the committee to revisit some of the earlier witnesses.”
Connolly told reporters Tuesday that there was “no question” that the need for the testimony of former National Security Adviser John Bolton “becomes more compelling every day.”
Bolton reportedly told Hill that he did not “not part of whatever drug deal Sondland and Mulvaney are cooking up,” in his objection to the pressure campaign run by Trump and his allies, including his lawyer, Rudy Giuliani.
He added that he wanted to see Giuliani, Acting White House Chief of Staff Mick Mulvaney, and Energy Secretary Rick Perry testify. (The White House has said that it will not comply with congressional subpoenas, and Perry and Giuliani have rejected subpoenas, and Mulvaney missed a deadline for documents.)
The testimony showed that Democrats’ efforts to compel career State Department officials were bearing fruit. Taylor, former Ambassador to Ukraine Marie Yovanovitch, who said that Trump ousted her from her post, and Hill, the former N.S.C. official have defied State Department and Trump Administrations instructions not to testify, and revealed damaging information about Trump and Giuliani.
House committees have compelled their testimony under subpoena. The inquiry has produced a whistleblower complaint, a White House transcript of the July 25 call between Trump and Zelensky, and texts by former Special Representative to Ukraine Kurt Volker, where Taylor wrote in a chain with Sondland that it was “crazy to withhold security assistance for help with a political campaign.”
Given that Democrats were still in fact-finding mode, the timeline for the inquiry remained uncertain. At the outset of the announcement of the inquiry, some House Democrats had envisioned an investigation with articles of impeachment ready to vote on before Thanksgiving.
That timeline seemed unlikely to be met, given that the House was only in session Wednesday for the rest of the week due to funeral services for Rep. Elijah Cummings (D-Md.), and for one more week after, before going on recess for a week and coming back for another two weeks before Thanksgiving.
House Intelligence Committee Chairman Adam Schiff (D-Calif.) has said that he plans to make parts of the closed-door testimony public and have witness testimony in public, though the timing for those steps remains unclear.
“That is the million dollar question,” said Rep. Pramila Jayapal (D-Wash.). “Every time somebody testifies, there’s five more people who we have to talk to, so that makes it very uncertain on timing.”
Majority Leader Steny Hoyer (D-Md.) told reporters at a briefing that there was a desire to conduct the inquiry “expeditiously,” but added, “whether that’s the end of the year or not we don’t know.”
What was clear was that some House Democrats hearing the testimony felt that they had possibly heard their most important witness thus far. “There’s a rich reservoir of information with respect to Ambassador [Bill] Taylor,” said Rep. Lynch. “This is a sea change.”
More must-read stories from Fortune:
—A running list of questions on the impeachment inquiry, answered
—5 lessons history has taught us about impeachment
—How Gordon Sondland, ‘a guided missile for getting access,’ landed in the middle of Trump’s Ukrainian mess
—How whistleblowers have taken down titans of American business
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