Story highlights Mukasey insisted that Comey's investigation "was mismanaged from the get-go"

The former Bush attorney general questioned Comey's move to notify Congress right before the election

New York (CNN) Former Attorney General Michael Mukasey said Saturday that FBI Director James Comey should resign in the wake of controversy surrounding his bureau's handling of the investigation into Hillary Clinton's email server, adding that President-elect Donald Trump should pardon Clinton.

Mukasey, who served under former President George W. Bush, insisted in an interview with CNN's Michael Smerconish that Comey's investigation "was mismanaged from the get-go."

"He crossed several lines. I think it was not his function to call to question whether she should or should not be prosecuted. That was for the attorney general or her designee, and I think he went way out of his lane," he said.

As for Comey's controversial move to notify Congress 11 days before the election of newly discovered emails that were thought to be potentially related to Clinton's server, Mukasey questioned his judgment.

"When he held the press conference -- and remember that Secretary Clinton's campaign billed that as a clean bill of health -- he was exonerating her. Then he then felt he had to correct the record, there might be more. Then he had to re-correct the record. It was like watching a car gradually go out of control," Mukasey said.

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