Attorney General William Barr gave his clearest explanation yet of the various “investigations of the investigators” being carried out by the Justice Department.

In an interview with CBS’s Jan Crawford, Barr described what tasks U.S. Attorney John Durham, Justice Department Inspector General Michael Horowitz, and U.S. Attorney John Huber have been assigned regarding the origins of the Trump-Russia investigation and the conduct of the DOJ and FBI as they carried it out.

Following pressure from congressional Republicans, then-Attorney General Jeff Sessions announced in March 2018 that Huber, a U.S. attorney from Utah, had been picked to review any misconduct by the DOJ and FBI. Some Republicans had been calling for a second special counsel.

Huber’s long-running inquiry has long been shrouded in mystery, but Barr revealed Horowitz and Durham have taken over most of his responsibilities.

Barr said “Huber had originally been asked to take a look at the FISA applications and the electronic surveillance” but that he then “stood back and put that on hold while the Office of Inspector General was conducting its review.”

Barr said Huber “was essentially on standby” in the event that Horowitz “referred a matter to him to be handled criminally.” That apparently has not been necessary, as Barr said “he has not been active on this front in recent months.” Barr said Durham would now be taking over Huber’s role in handling any criminal referrals from Horowitz and Huber’s involvement with Trump-Russia matters was done.

Sessions had also asked Huber in 2017 to look into issues related to the sale of Uranium One and allegations that former Secretary of State Hillary Clinton had been improperly involved in the process, as well as broader claims of corruption at the Clinton Foundation. Barr seemed to suggest that what evidence Huber found, if any, may soon be revealed.

"The other issues [Huber has] been working on relate to Hillary Clinton” are "winding down and hopefully we'll be in a position to bring those to fruition," Barr said.

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In regards to the DOJ inspector general investigation, Barr said he would not describe Horowitz’s role as small, but rather as very specific. “He’s looking at a discrete area that is, you know, important, which is the use of electronic surveillance that was targeted at Carter Page," Barr said. Page was a former Trump campaign adviser who was surveilled by the DOJ and the FBI for months beginning in October 2016.

More than a year ago, in March 2018, Horowitz announced the start of the FISA abuse investigation, saying he was doing so following requests from Sessions and Republican members of Congress. GOP lawmakers alleged the DOJ and FBI had abused the FISA process and misled the Foreign Intelligence Surveillance Court in their investigation and surveillance of Trump and his associates during the campaign and Trump's administration.

At the time, the inspector general's office said it would “examine the Justice Department’s and the FBI’s compliance with legal requirements, and with applicable DOJ and FBI policies and procedures, in applications filed with the U.S. Foreign Intelligence Surveillance Court (FISC) relating to a certain U.S. person.” That “certain U.S. person” is Page.

The DOJ inspector general also said it would “review information that was known to the DOJ and the FBI at the time the applications were filed from or about an alleged FBI confidential source. Additionally, the OIG will review the DOJ’s and FBI’s relationship and communications with the alleged source as they relate to the FISC applications.” The “source” is Christopher Steele, the British ex-spy whose unverified dossier was used by the FBI to obtain FISA warrants against Page.

Steele has communicated in recent days that he’d be willing to cooperate with Horowitz but not with Durham.

Barr, who has said that Horowitz’s probe should be ending in May or June, called him a “superb government official” in this latest interview, but pointed out that Horowitz “has limited powers.”

“He doesn't have the power to compel testimony, he doesn't have the power really to investigate beyond the current cast of characters at the Department of Justice,” Barr said. “His ability to get information from former officials or from other agencies outside the department is very limited.”

That’s why Barr said he selected Durham, a U.S. attorney for Connecticut, to head up DOJ’s newest inquiry. Barr was recently given broad declassification authority by Trump, and Durham will have greater investigative powers than Horowitz has at his disposal. Barr praised Durham, saying, “He has, over the years, been used by both Republican and Democratic attorneys general to investigate these kinds of activities. And he's always gotten the most laudatory feedback from his work. So there's no doubt in my mind that he's going he's going to conduct a thorough and fair review of this.”

Barr defended his scrutiny of the actions of the DOJ and FBI in his CBS interview, saying, “I think it's important to understand what basis there was for launching counterintelligence activities against a political campaign, which is the core of our … First Amendment liberties in this country.”

“And what was the predicate for it? What was the hurdle that had to be crossed? What was the process? Who had to approve it? And including the electronic surveillance, whatever electronic surveillance was done? And was everyone operating in their proper lane?” Barr asked.