Indeed, the speech was a stark departure from the prosecutor’s rule of thumb that you should say it in an indictment or you shouldn’t say it at all. But former prosecutors said it was a justified exception to assure the public of the probe’s independence in an extraordinarily contentious case, especially given the controversy surrounding Bill Clinton’s meeting with Comey’s boss, Attorney General Loretta Lynch…

“It’s not just unusual, it’s unprecedented,” said Matthew Miller, who was director of the Office of Public Affairs for the Department of Justice under Attorney General Eric Holder and now works at strategic advisory firm Vianovo. “He’s put himself into the middle of a political campaign in a way that will call into question the legitimacy of the office.”

“You’ll now have people in the middle of a campaign able to say, ‘Well, the FBI director said Hillary Clinton was careless,'” Miller added. “That’s not the FBI director’s job to do, and the rules are set up to prohibit that kind of behavior.”