White House acting chief of staff Mick Mulvaney would leave the room whenever President Donald Trump met with his attorney Rudy Giuliani to discuss the Ukraine scheme.
Mulvaney, who also serves as director of the Office of Management and Budget, left the room for those discussions to preserve the president's attorney-client privilege with Giuliani, according to associates who spoke with the New York Times.
That left Mulvaney with limited knowledge of Trump and Giuliani's efforts to pressure Ukraine to announce an investigation of Joe Biden and his son, and which became the basis of the president's impeachment.
Mulvaney has told associates he learned what Trump discussed with Ukrainian president Volodymyr Zelensky weeks after their July 25 phone call, which prompted a whistleblower complaint and then the impeachment inquiry.
But impeachment witnesses told House investigators otherwise.
Fiona Hill, a top deputy to then-national security adviser John Bolton, testified that EU ambassador Gordon Sondland told White House officials July 10 that Mulvaney had guaranteed Zelensky would be invited to the White House if he agreed to announce the investigation.
The former national security adviser described that arrangement as a "drug deal," according to Hill, and resigned as the scheme came to light in September.
Bolton, Mulvaney and his aide Robert Blair have all refused to cooperate with the impeachment inquiry.
Mulvaney infamously declared that efforts to withhold military aid from Ukraine in exchange for the investigations was "absolutely appropriate" and a common practice by U.S. administrations.
"I have news for everybody," Mulvaney said Oct. 17 during a White House news conference. "Get over it. There is going to be political influence in foreign policy."