It's hard to say exactly why former top FBI official Andrew McCabe was fired Friday night, hours before he was set to retire with full benefits. The top line from the man who fired him, Attorney General Jeff Sessions, is that McCabe authorized the FBI to talk to the media about a Hillary Clinton-related criminal inquiry, then “lacked candor” when internal investigators asked him about it.

That's all we know for now. The details aren't public because the Justice Department hasn't yet released a report from its own internal watchdog.

The lack of transparency on McCabe's firing leaves room for both sides to say this is really about Russia.

McCabe has said his firing is the latest salvo in an “ongoing war” on the FBI and the special counsel investigating Trump-Russia connections. President Trump immediately pivoted from McCabe's firing over how he handled an aspect of a Clinton investigation to attacking the entire FBI for its ongoing investigation of him.

To get a better sense of who's closest to the truth, let's dig into the allegations. But first, some background about how this all got started.

The Justice Department's internal watchdog is looking into how the FBI handled its election-year investigation of Clinton's use of a private email server. The internal investigation isn't done yet, but Inspector General Michael Horowitz has concluded that McCabe did two things wrong:

  1. He allowed two FBI officials to speak to the media about a separate criminal investigation of the Clinton Foundation.
  2. When DOJ investigators asked McCabe about this, he misled them.

Based on those findings, the FBI office that handles discipline recommended that McCabe be fired. Sessions did so, after lots of tweets by Trump attacking both Sessions and McCabe.

Now, let's break down the allegations.

Allegation No. 1: McCabe gave a green light to FBI officials under him to talk to the Wall Street Journal during the presidential campaign for a story about FBI feuding in its investigation of the Clintons' family foundation.

Here's why the Justice Department watchdogs think that's wrong: The FBI rarely shares information, let alone specific, sensitive details that were in that Wall Street Journal story, about an ongoing criminal investigation.

What McCabe is saying: He's not denying authorizing the conversations with the media, but he is combating the narrative that there was anything wrong with that. He said in a statement that he wanted to “set the record straight” from the FBI's perspective and that he saw nothing out of the ordinary in wanting to do that: “It was the type of exchange with the media that the Deputy Director oversees several times per week.”

What Trump is saying: Less about the media conversations and more about the fact McCabe was fired. He claims that proves that the top levels of the FBI were biased against him.

Except, that falls apart when you examine the story McCabe authorized his agents to talk about. It was about an investigation of the Clinton family foundation, and at one point, McCabe is reported to have defended the ongoing inquiry from Justice Department officials who questioned why it was still going on. “Are you telling me that I need to shut down a validly predicated investigation,” McCabe is said to have asked.

Allegation No. 2: McCabe “lacked candor” about his involvement in authorizing investigators to talk to the media, including when he was interviewed under oath.

This is the murkier allegation to suss out. “Candor” isn't measurable in the abstract, said Cornell Law School Vice Dean Jens David Ohlin: “How can we assess 'lack of candor' without the transcript of [investigator] interviews [with McCabe]?”

What McCabe is saying: McCabe blamed any lack of clarity or candor on “the chaos that surrounded me.” In a statement, he said he “answered questions truthfully and as accurately as I could amid the chaos that surrounded me. And when I thought my answers were misunderstood, I contacted investigators to correct them.”

His broader point is that his firing was an effort by the Trump administration to discredit a top official in the FBI (him), and thus the entire FBI, and thus the special counsel working with the FBI to investigate the president.

“This attack on my credibility is one part of a larger effort not just to slander me personally, but to taint the FBI, law enforcement, and intelligence professionals more generally,” McCabe said.

What Trump is saying: Trump is kind of backing up McCabe's point that this is really about Russia, Ohlin said. The president went on a remarkably candid Twitter tear over the weekend, attacking the FBI for “leaking, lying and corruption,” and then leapfrogging to attack the special counsel investigation of him, which was set up by Deputy Attorney General Rod J. Rosenstein, not McCabe and the FBI.

Trump's approach seems to be this: Go after anyone in the FBI who is alleged to have done something wrong to prove that the FBI can't be trusted as it works with the special counsel to investigate him.

And Trump could have a special interest in lumping McCabe into that category of untrustworthy law enforcement officials. McCabe is a witness in the Russia probe, and he may have key evidence when it comes to Robert S. Mueller III's investigation of whether the president obstructed justice. It appears that just like Comey, McCabe kept detailed memos about his conversations with the president, like when the president asked him whom he voted for in the presidential election.

And that suggests that McCabe was concerned enough with what the president was saying to him to write it down for an occasion such as this.

As my Fix colleague Aaron Blake pointed out, whether McCabe was fired for fair reasons may be less important than the fact that Trump just created a motivated, potentially powerful enemy.