Has Robert Mueller taken a recent interest in a memo drafted at the time of James Comey’s firing as evidence of obstruction? Or is the New York Times’ scoop from yesterday a bit of old news that just happened to shake loose recently? Former Comey deputy Andrew McCabe has turned over a memo-to-file he wrote immediately after meeting with deputy Attorney General Rod Rosenstein in the wake of Comey’s departure. Its contents suggest that Rosenstein may have been working on “a cover story” for Comey’s firing, but that’s not the only explanation possible here:

In the document, whose contents have not been previously reported, Mr. McCabe described a conversation at the Justice Department with the deputy attorney general, Rod J. Rosenstein, in the chaotic days last May after Mr. Comey’s abrupt firing. Mr. Rosenstein played a key role in the dismissal, writing a memo that rebuked Mr. Comey over his handling of an investigation into Hillary Clinton.

But in the meeting at the Justice Department, Mr. Rosenstein added a new detail: He said the president had originally asked him to reference Russia in his memo, the people familiar with the conversation said. Mr. Rosenstein did not elaborate on what Mr. Trump had wanted him to say.

To Mr. McCabe, that seemed like possible evidence that Mr. Comey’s firing was actually related to the F.B.I.’s investigation into the Trump campaign’s ties to Russia, and that Mr. Rosenstein helped provide a cover story by writing about the Clinton investigation.

For what it’s worth, Trump offered this rebuttal today:

NBC offered a rebuttal of Trump’s rebuttal from, er … Trump:

But is “cover story” and “obstruction” the only interpretation possible? The Times provides one alternate explanation in the very next paragraph:

One person who was briefed on Mr. Rosenstein’s conversation with the president said Mr. Trump had simply wanted Mr. Rosenstein to mention that he was not personally under investigation in the Russia inquiry. Mr. Rosenstein said it was unnecessary and did not include such a reference. Mr. Trump ultimately said it himself when announcing the firing.

That seems much more likely to be the case, given all the exigent circumstances, but one doesn’t even need to go that far to poke a big hole in the Times’ presentation of McCabe’s argument. If Trump needed a cover story, it would have been to distract away from the Russia probe as a proximate cause of Comey’s firing. Why would he push Rosenstein to create a cover story and at the same time demand that Rosenstein mention Russia in the memo?

On the other hand, the idea that Trump fired Comey because he broke protocol on the Hillary Clinton investigation and made her look unnecessarily bad doesn’t exactly hold water, either. There may have been good reasons to fire Comey for that, but that’s an argument for firing him in January or early February, not May. Comey got fired not because of his bad choices in handling the Clinton investigation, but — as the Times notes — because Comey wouldn’t extend the same courtesies to Trump and publicly note that he was not a target of the Russia investigation. That may be an unwise and self-serving motive, although one can craft an argument that it was also about preserving the effectiveness of the office, but either way it’s not obstruction of justice.

Here’s another question: why is this leaking now, and who leaked it? Unlike some previous leaks about the Mueller probe, this one doesn’t seem likely to have come from Trump’s legal team. If it’s leaking from the special counsel probe, it would be a strange tidbit to drop now. This evidence should have been collected a year ago, and likely was, when Mueller first got appointed special counsel. He would have had almost unfettered access to the FBI’s internal documents.

This seems more like a leak from someone close to McCabe instead. Don’t forget that McCabe may face criminal charges of obstruction of justice himself, thanks to a criminal referral from the Inspector General that detailed lies and misleading statements to FBI investigators looking into a leak about the Hillary probe. The IG report just dropped five weeks ago, and a decision on prosecution hasn’t yet been publicly made by the Department of Justice. Having this memo drop into the public square might be an effort to suggest that any prosecution will be retaliatory, as well as a means to discredit McCabe as a potential Mueller witness.

Of course, the IG report itself did most of the damage there anyway. Even if Mueller saw this as evidence of a cover-up, he’d be hard pressed to use it. McCabe has been credibly accused of obstruction himself by offering lying and/or misleading testimony. What’s he going to say — “Yes, I lied internally before, but you can totally trust me now”? No experienced prosecutor would rely on a witness with that background, especially when the evidence comes from an independent investigator. If there’s anything to the “cover story” allegation here, it’s going to have to come from someone other than McCabe.