Attorney General Jeff Sessions faces a decision that will be controversial no matter what he does: Fire former Deputy FBI Director Andrew McCabe, or overrule the recommendation of the FBI’s own internal investigators.

The recommendation to fire Mr. McCabe isn’t coming from Donald Trump or Russian bots. It comes from the FBI’s Office of Professional Responsibility. News reports say it is based on a finding from the Justice Department’s Inspector General that Mr. McCabe authorized the disclosure of sensitive information to a Wall Street Journal reporter about the investigation into the Clinton Foundation—and then lied about it to IG investigators.

The IG report remains secret, but it’s hard to believe the FBI would recommend such punishment if it did not believe Mr. McCabe’s actions were a serious breach of duty. The bureau’s recommendation is in marked contrast to the endorsement from his old boss, former FBI Director James Comey, who tweeted in January that Mr. McCabe “stood tall” as “small people were trying to tear down an institution we all depend on.” Did St. Jim know about his comrade’s alleged deception?

Mr. McCabe is connected to controversial FBI investigations into both presidential candidates in 2016, and in January he said he would formally retire on March 18 when he would have enough seniority to qualify for his pension. Firing him early could cost him that lifetime payout.

The American people still don’t know what went on at the FBI during those 2016 investigations. Several FBI and Justice officials will soon testify to the House Intelligence Committee. Perhaps Mr. McCabe’s firing would persuade them that there are consequences for untruthfulness. Time and again we have been assured of the FBI’s high standards. Imagine how Mr. McCabe would treat an American citizen who lied to the FBI.