"If necessary, we will call Bob Mueller or others before our committee, I would imagine the judiciary committee may call the attorney general if necessary,"

"At the end of the day, the department is under a statutory obligation to provide our committee with any information regarding significant intelligence activities, including counterintelligence. And it's hard to imagine anything more significant than what Bob Mueller has been investigating."

"We have a right to be informed, and we will demand to be informed about it."

Schiff said that during the last Congress, the Justice Department turned over 880,000 pages of evidence from the Hillary Clinton email investigation, even though no one was ever indicted. Mueller's special counsel investigation has already led to 37 indictments, though the final report reportedly does not recommend any additional ones.

"We need to point out to the department it would be establishing a horrendous double standard," Schiff said.

If the department does not release the report and underlying evidence, Schiff said Democrats would use their authority as the majority party in the House of Representatives to compel the release of Mueller's findings.