January 15, 2020 -President Donald Trump and Senate Majority Leader Mitch McConnell (R-KY) are engaged in a cover-up by trying to prevent the Senate from holding a fair impeachment trial. They are attempting to block witnesses from testifying because it is clear that these witnesses will provide damning evidence against the president.

Most of what we know about these potential witnesses’ roles has come from testimony or press reports. In some cases, such as those of Secretary of State Mike Pompeo and Acting Chief of Staff Mick Mulvaney, it also comes from public statements they themselves have made.

Pompeo, Mulvaney, former national security adviser John Bolton, and Vice President Mike Pence can testify to the president’s direct involvement in the plot to extort Ukraine. The other witnesses, who played roles in implementing the White House’s scheme, can shed light on what they did and on whose orders they did it. Furthermore, the documents they possess could corroborate the allegations against Trump. It is vital that Congress and the American public learn the truth—which means it is vital that the Senate hold a full trial and demand that the administration produce the witnesses and documents it is trying desperately to hide.

Trump’s defenders in Congress claim that they have heard no firsthand evidence of Trump’s abuses of power. That’s because Trump has stonewalled Congress, preventing those with firsthand knowledge from testifying or producing documents. To rectify that, here are 11 witnesses the Senate should call to testify in the impeachment trial and what they should be asked about.

Former national security adviser John Bolton

  • The “drug deal”: Bolton was at the July 10 meeting where Ambassador to the European Union Gordon Sondland explained the quid pro quo to the Ukrainians. According to National Security Council (NSC) official Fiona Hill, Bolton told Hill he would not be part of Sondland and Mulvaney’s “drug deal,” instructed Hill to speak with NSC lawyers, and said, “[Trump lawyer Rudy] Giuliani’s a hand grenade who’s going to blow everybody up.”
  • August meeting: Bolton reportedly attended the meeting in August where he and other top officials, including Secretary of State Pompeo and Secretary of Defense Mark Esper, tried to persuade Trump to release the military aid to Ukraine.

Key questions

  • Why did Bolton tell Hill to speak with NSC lawyers?
  • Why did Bolton describe Sondland and Giuliani’s efforts as a “drug deal”?
  • How did Trump and the White House justify their decision not to release the military aid to Ukraine?
  • Was Bolton present at any other meetings where the hold on aid was discussed?

Acting White House Chief of Staff/Office of Management and Budget (OMB) Director Mick Mulvaney

  • Oversaw pressure campaign: As both acting White House chief of staff and OMB director, Mulvaney oversaw both negotiations for a potential White House visit for Ukrainian President Volodymyr Zelensky and the freeze on military aid to Ukraine.
  • Instructed the OMB to hold the aid to Ukraine: Witness testimony and emails have made clear that Mulvaney instructed the OMB to put a hold on Ukraine’s security assistance.
  • Coordination with Sondland: Testimony and texts show Sondland coordinating with Mulvaney.
  • October 17 press conference: Mulvaney confirmed the quid pro quo with Ukraine in an October 17 press conference, telling reporters that “we do this all the time” and that they should “get over it.” (Mulvaney has since attempted to walk back his admission.)
  • Cover-up: The OMB cut out career staff during the hold on aid to Ukraine, including shifting oversight of the hold to a political appointee in the OMB. Additionally, at least two OMB officials reportedly resigned over the hold on aid.

Key questions

  • Did Trump direct Mulvaney to hold the aid to Ukraine, and what reasons were provided for this action?
  • What conversations did Mulvaney have with Sondland and the others responsible for executing Trump’s extortion scheme?
  • What meetings did Mulvaney attend where military aid and the White House meeting were discussed?
  • Was Mulvaney in contact with Rudy Giuliani about his efforts in Ukraine?
  • Why did the OMB reassign key decision-makers surrounding the hold on aid, and what does Mulvaney know about the two officials who reportedly resigned?
  • What instructions was Mulvaney given prior to his October 17 press conference?

Vice President Mike Pence

Key questions

  • Was Pence informed why he would not be attending Zelensky’s inauguration?
  • Did Pence receive a readout of Trump and Zelensky’s July 25 call?
  • When, and how explicitly, was Pence made aware that Giuliani and Sondland were seeking to get Zelensky to announce an invetigation into Trump’s political opponents?

Secretary of State Mike Pompeo

  • Yovanovitch firing: Pompeo declined to defend former Ambassador to Ukraine Marie Yovanovitch against a smear campaign that was carried out because she wouldn’t support Trump’s pressure campaign and that ultimately led to her being recalled from Ukraine early.
  • Giuliani’s “dossier”: Pompeo reportedly reviewed a “dossier” of conspiracy theories from Giuliani.
  • August meeting: Pompeo reportedly attended the August meeting in which he, Bolton, and Esper tried to convince Trump to release aid.

Key questions

  • Why did the State Department recall Yovanovitch when the deputy secretary of state told her she did nothing to merit being recalled?
  • Was Pompeo, or any other State Department official, aware of the apparent effort—revealed in text messages between indicted Giuliani associate and Trump legal team member Lev Parnas and Republican congressional candidate Robert Hyde—to surveil and potentially intimidate Yovanovitch in conjunction with the smear campaign? Was the State Department’s regional security officer in Kyiv aware of this surveillance? Is the State Department investigating whether individuals in the embassy in Kyiv were providing information on the ambassador’s movements to Parnas?
  • What was Pompeo’s response to receiving Giuliani’s dossier outlining various conspiracy theories?
  • How did Bolton, Pompeo, and Esper attempt to persuade Trump to release aid, and how did Trump justify his decision not to do so?

Attorney General William Barr

  • Anti-Mueller investigation: Trump has deputized Barr to run an investigation to undermine the credibility of the Mueller investigation, including by asking other countries for information.
  • July 25 call: In the July 25 call, Trump instructed Zelensky to discuss potential investigations with both Giuliani and Barr, suggesting that Trump sees their efforts to substantiate Ukrainian interference conspiracy theories and undermine special counsel Robert Mueller, respectively, as two parts of the same effort.
  • Whistleblower complaint: Despite being named in the whistleblower complaint about Trump’s extortion scheme, Barr didn’t recuse himself when the Department of Justice (DOJ) advised Acting Director of National Intelligence (DNI) Joseph Maguire not to provide the complaint to Congress.

Key questions

  • Prior to the July 25 call, was Barr aware that Trump wanted him to coordinate with the Ukrainian government on potential investigations into Trump’s political opponents?
  • What other investigations into his political opponents has Trump asked Barr to pursue?
  • What, if any, role did Barr play in the DOJ’s advice to the DNI not to transmit the whistleblower complaint to Congress?

Former Secretary of Energy Rick Perry

  • “Three amigos”: Perry was one of the “three amigos” Trump had running his agenda in Ukraine, alongside Sondland and former Special Envoy to Ukraine Kurt Volker. He was also the one who initially contacted Rudy Giuliani to open the “irregular channel” of diplomacy.
  • Zelensky’s inauguration: When the White House decided that Pence would not be attending Zelensky’s inauguration, it sent Perry instead.
  • July 10 meeting: Perry was at the July 10 meeting in which Sondland raised the quid pro quo to the Ukrainians. He was also on a June 28 call in which Volker said that Zelensky had to announce investigations to get a White House meeting.
  • Naftogaz board: Perry was reportedly pressuring Ukraine to put a top political donor on the board of the Ukrainian state-run energy company Naftogaz. This effort appears to have occurred at the same time as Parnas and his associate Igor Fruman’s efforts to effectuate changes to the board; it remains unknown if there was any connection between the two.
  • Willing to cooperate: Perry has said he is willing to cooperate with Congress if called to testify.

Key questions

  • What did Perry know at the time about the “three amigos” and the role of the irregular channel in Trump’s extortion scheme?
  • What did Perry know about why he was sent to Zelensky’s inauguration instead of Pence?
  • Was there any connection between Perry’s efforts to change the board of Naftogaz, Parnas and Fruman’s efforts to do the same, and the extortion scheme?

National Security Council lawyers John Eisenberg and Michael Ellis

  • Fiona Hill: According to Hill, after the July 10 meeting, Bolton instructed Hill to inform Eisenberg and Ellis about Sondland’s offer to Zelensky’s aides of a White House meeting in exchange for investigations.
  • July 25 call: After the July 25 phone call, Col. Alexander Vindman and NSC official Tim Morrison also spoke to Eisenberg and Ellis, who allegedly told Vindman to keep the call secret.
  • Secret server: Eisenberg reportedly made the decision to move records of the July 25 call to a secret, secure server.

Key questions

  • Why did Eisenberg decide to move the record of the call to a secret server? Who did he consult about the decision?
  • How did Eisenberg and Ellis respond when Hill informed them of what happened at the July 10 meeting?
  • Why did Eisenberg and Ellis instruct Vindman to keep what he heard on the July 25 call secret?
  • Morrison testified that he alerted Eisenberg and Ellis about the July 25 call because he was worried about political blowback and that moving the call to a secret server was “an administrative error.” Are these statements true?

OMB officials Russell Vought and Michael Duffey

  • Emails about aid freeze: According to The New York Times, the White House has acknowledged the existence of at least 20 emails between Vought and Duffey about withholding aid to Ukraine that the White House refuses to turn over to press or Congress.
  • Relaying directions from Trump of a “sensitive nature”: Duffey told the Department of Defense that he had “clear direction from POTUS to continue to hold [military aid].” In another email, he told the DOD to keep information about the aid closely held “given the sensitive nature of the request.”
  • Duffey was told holding the aid was illegal: The Department of Defense told Duffey that holding the aid into late August would mean the money could not be spent, violating the Impoundment Control Act. But Duffey kept withholding the aid anyway.

Key questions

  • What did Vought and Duffey say in their emails about the hold on military aid?
  • What exactly did Duffey mean when he said he had “clear direction from POTUS?”
  • Why did Duffey consider information about the hold, which the administration maintains was relatively routine and entirely aboveboard, to be of a “sensitive nature”?
  • What was Duffey’s response when he was told that withholding aid was likely illegal? Who did he consult about the decision to continue doing so?

OMB official Brian McCormack

As Perry’s throughout much of the Ukraine scandal, McCormack could answer questions about Perry’s attendance at Zelensky’s inauguration, his work as one of the “three amigos,” and his efforts to pressure Ukraine to appoint a political donor to the board of Naftogaz.

  • Work for Perry: As Perry’s chief of staff throughout much of the Ukraine scandal, McCormack could answer questions about Perry’s attendance at Zelensky’s inauguration, his work as one of the “three amigos,” and his efforts to pressure Ukraine to appoint a political donor to the board of Naftogaz.
  • At meetings where the quid pro quo was discussed: McCormack was at the July 10 meeting, as well as a follow-up meeting later that day in which Sondland repeatedly raised the quid pro quo.
  • In the loop: McCormack was on email chains between Sondland and high-ranking White House staff about the quid pro quo.

Key questions

  • What does McCormack know about Perry’s role in the “three amigos” and his efforts to get a political donor appointed to the board of Naftogaz?
  • What other meetings did McCormack attend in which the quid pro quo was discussed? What other email chains was he on in which the quid pro quo was discussed?

Jeremy Venook is a research analyst for the Moscow Project at the Center for American Progress Action Fund. Max Bergmann is a senior fellow at the Action Fund.

This article was published by the Center for American Progress Action Fund.  www.americanprogressaction.org