Special Counsel Robert Mueller's investigation of allegations of collusion between Russian officials and the Trump 2016 campaign had "no legitimate predicate," Senate Homeland Security Committee chairman Ron Johnson, R-Wis., told "Bill Hemmer Reports" Friday.

Johnson was responding to a Fox News report that the primary source for the anti-Trump dossier compiled by ex-MI6 agent Christopher Steele had been the subject of an FBI counterintelligence investigation from 2009 to 2011 over suspected contact with Russian intelligence officers.

"Certainly there was no legitimacy to continuing [the Russia investigation] any time past January 2017, because in early October 2016 ... they had information that the sub-source might have ties to Russian intelligence, could have been a former KGB officer," Johnson told host John Roberts.

"By December, they knew that their own FBI had investigated this individual as a possible Russian intelligence officer," the senator continued. "Then, of course, in January 2017, they actually interviewed the sub-source and we found out these comments [in the dossier] were never intended to be made part of a report, they were just rumors, [people] kind of talking over a couple beers.

SOURCE OF STEELE DOSSIER WAS INVESTIGATED BY FBI OVER RUSSIAN CONTACTS

"So the FBI was well aware of how unreliable the Steele dossier was, and yet in March of 2018, the FBI briefed the Senate Intelligence Committee and still claimed that the Steele dossier was reliable," Johnson added. "So, no, [the Russia investigation] should have been shut down by the end of January [2017]. We never should have had a special counsel."

Later in the interview, Roberts asked Johnson about comments by an FBI agent who served on the Mueller team and claimed in an interview earlier this month that "there was a 'get Trump' attitude" exhibited by some members of the investigation.

FBI OFFICIAL ON MUELLER TEAM SAID FLYNN PROSECUTION HAD A 'GET TRUMP' ATTITUDE

FBI agent William J. Barnett made those comments during an interview on Sept. 17 at the Justice Department before Assistant U.S. Attorney for the Eastern District of Missouri Jeffrey Jensen. Jensen had been tapped by Attorney General Bill Barr to review the case against Flynn.

"When you take a look at that 15-page interview memo just released by Attorney General Barr, what you will find out is the lawyers running the special counsel operation had their predetermined outcome," Johnson said. "So they used people like Mr. Barnett, the investigators, as sort of errand boys.

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"Basically you have the court approvals already predetermined and have the FBI agents as the lackeys to go do the bidding of [the] special counsel. That's not the way these things work," Johnson continued. "Again, I think we need to do a true investigation into the special counsel operation ... we need documents to determine exactly how much corruption was there in the entire Crossfire Hurricane investigation.

"This is a major scandal [and] the mainstream media continues to look the other way."

Fox News' Brooke Singman contributed to this report.