Testifying before the House Judiciary Committee Wednesday, FBI Director James Comey revealed it wasn't the FBI that granted longtime Clinton aide and attorney Cheryl Mills immunity during the criminal investigation of Secretary Clinton's private email server. Instead, it was granted by prosecutors at the Department of Justice.

"Who authorized granting Cheryl Mills immunity?" Rep. John Sensenbrenner asked.

"It's a decision made by the Department of Justice, I don't know at what level inside," Comey responded. "In our investigations, any kind of immunity comes from the prosecutors, not the investigators."

Comey added he understood Mills' immunity as a request pertaining to the production of her laptop during the investigation.

"The FBI doesn't grant immunity to anybody, the Department of Justice is able to grant very different kinds of immunity," Comey said. "If new and substantial evidence develops a witness lied [under immunity], of course the Department of Justice can pursue it. Nobody gets lifetime immunity."

Last week Oversight Committee Chairman Jason Chaffetz accused the FBI of handing out immunity in the case "like candy." Comey said today the immunity granted in the case was "ordinary investigative process."