The Mueller questions to Kelly centered on a narrow set of issues in the investigation of potential obstruction of justice, chiefly Kelly’s recollection of an episode that took place after new reporting emerged about how the President had tried to fire Mueller. The President was angry at then-White House counsel Don McGahn about what had been reported by The New York Times. McGahn had refused to publicly deny the reporting. The special counsel wanted to try to corroborate McGahn’s version of events.

The White House counsel’s office had initially fought the Mueller request. One source familiar with the matter said that Emmett Flood wanted to make sure “ground rules” were negotiated.

“In order to question a government official about things that happened during the course of government business, you’ve got to show that it’s highly important and you can’t get it anywhere else,” the source said.