One reason it's so hard to believe the official justification for firing James Comey as head of the FBI: Even Attorney General Jeff Sessions does not believe it. Sessions, whose recommendation supposedly prompted President Trump to give Comey the boot, has publicly and repeatedly defended the actions he now cites as reasons for replacing the FBI director.

The memo in which Deputy Attorney General Rod Rosenstein lays out the case for firing Comey makes some familiar points about the way he handled the investigation of Hillary Clinton's email practices as secretary of state. Rosenstein criticizes Comey for calling a press conference on July 5 to explain why he was not recommending criminal charges against the Democratic presidential nominee. He also faults Comey for announcing, in a letter to members of Congress just 11 days before the election, that the FBI had come across another email trove that might include evidence relevant to the Clinton investigation.

Rosenstein's arguments are compelling, but they are no stronger now than they were last July or last October, when Sessions rejected them. Yet Sessions now claims to believe Comey's behavior was so egregious that "a fresh start is needed at the leadership of the FBI" so that the Justice Department can "reaffirm its commitment to longstanding principles that ensure the integrity and fairness of federal investigations and prosecutions."

Two days after Comey's press conference, where he harshly criticized Clinton's "extremely careless" handing of classified material even as he insisted that "no reasonable prosecutor" would bring a case against her, Sessions, then an Alabama senator and a leading Trump supporter, appeared on Greta Van Susteren's Fox News show. "This was a difficult case," he said, according to the Nexis transcript. "I think it clearly could have gone the other way." Sessions, a former U.S. attorney, said there seemed to be enough evidence for at least a misdemeanor charge against Clinton. But he conceded that "I haven't studied the facts" and described Comey as "a skilled former prosecutor" whom "I have respected over…the years."

Sessions gave no hint that he disapproved of Comey's press conference, which (as Rosenstein notes) broke with the FBI's usual practice of leaving prosecution decisions to the Justice Department and avoiding the release of derogatory information about people who have been investigated but do not face charges. To the contrary, when Van Susteren said she "really appreciated [Comey's] transparency," since "the American people wanted to know…what his opinion was and how he arrived at it," Sessions replied, "It's not him that has the problem. It's Hillary Clinton."

Comey has argued that he needed to announce the outcome of the investigation because Attorney General Loretta Lynch had been compromised by her chumminess with the Clintons, as evidenced by a 20-minute conversation with Bill Clinton aboard her plane at a Phoenix airport on June 27. The criticism provoked by that "regettable" meeting with the former president had prompted Lynch to announce that she would automatically follow the FBI's recommendations concerning charges against Clinton to avoid any appearance of bias. But as Rosenstein notes, Comey could have asked Lynch to recuse herself from the case and let another Justice Department official announce the outcome rather than take on that task himself.

Sessions nevertheless endorsed Comey's defense of the press conference in an October 28 interview with Lou Dobbs on the Fox Business Network. "I didn't like the meeting that you mentioned on the airplane that put Comey in a position that he had to make this announcement," Sessions said. In the same interview, Sessions emphatically defended the other decision cited in Rosenstein's memo: "He had an absolute duty, in my opinion, 11 days or not, to come forward with the new information that he has and let the American people know that."

Last fall Sessions said Comey "had to make this announcement" and "had an absolute duty" to follow up with his letter about newly discovered evidence shortly before the election. Now Sessions says those are firing offenses. "Almost everyone agrees that the Director made serious mistakes," Rosenstein writes. But not Rosenstein's boss, at least not when those mistakes were helping the Trump campaign.