In the hubbub Monday over whether Deputy Attorney General Rod J. Rosenstein had resigned or been fired — turns out neither! (at least not yet) — one source told The Washington Post that Rosenstein “felt very compromised” at this point in time.

And that may be an undersold takeaway here. For all the talk about whether President Trump is going to fire Rosenstein or force him out using a story from the New York Times on Friday as a pretext to do so, Rosenstein’s proximity to the Russia investigation was already lurking beneath the surface. The story might have tipped the scales for President Trump, but it also might have done so for Rosenstein.

Although Rosenstein was previously potentially what’s known as a “fact witness” in the case, on Friday he became a potential fact witness with a potential neutrality problem.

To be clear, Rosenstein has denied Friday’s story that he seriously broached secretly recording meetings with Trump and invoking the 25th Amendment to remove the president from office. But even the perception that he is tainted could play into a decision about recusing himself or resigning.

The first time Rosenstein’s actions were at issue in the inquiry dates to before special counsel Robert S. Mueller III was even appointed. Rosenstein, you may recall, was the one who wrote the memo criticizing then-FBI Director James B. Comey’s stewardship of the FBI, a memo that was originally offered as the reason for Comey’s termination.

Once Trump went on NBC News with Lester Holt and suggested that the real reason was the Russia investigation, Rosenstein’s memo became less operable. Reports have indicated that Rosenstein felt used by Trump. Within days, he was reportedly talking about using a wire and the 25th Amendment.

But I wrote in May that some legal experts were already questioning whether this episode by itself meant Rosenstein should have recused himself from the Russia investigation, as Attorney General Jeff Sessions had. That’s because Rosenstein had the potential to be a fact witness in the inquiry.

Then came one of Andrew McCabe’s memos. In a contemporaneous account, we learned that the former deputy FBI director said Rosenstein had told him that Trump had asked that the Comey memo mention Russia. I wrote then:

Rosenstein’s memo was already part of the case, but it wasn’t clear whether he had actually been instructed by Trump in any way. If Trump told Rosenstein to include Russia in the memo and Rosenstein opted not to, that arguably makes him even more of what is known as a “fact witness” in the case.

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The story from Rosenstein’s side is that this was merely a reference to Trump’s frustration that Comey would not say publicly that Trump wasn’t under investigation in the Russia probe. And that makes sense, given that we previously knew about a draft letter Trump wrote laying out the reasons for Comey’s firing that included this frustration.

On Monday, another of McCabe’s memos (which were also the source of Friday’s Times story) has drawn Rosenstein even more into the situation — and in a way that makes it more difficult for him to look like a neutral overseer. Even if Rosenstein is just perceived as not being an impartial overseer, that could undermine whatever decisions he ultimately has to make — and whatever resolution might come. It seems possible that he may decide that, even if he feels wronged by this whole thing, exiting is the right thing to do. It’s one thing to stick around and fight back; it’s another to hurt the investigation in a vain attempt to clear your name.

Rosenstein has long been supported by both Democrats and Republicans who are worried about Trump taking a chain saw to the Russia investigation and causing a constitutional crisis. But that glossed over real questions about whether he should be in that job in the first place. For a law-enforcement man like Rosenstein, that has to be something he has considered.

That calculus became much tougher Friday. Now we find out whether he still thinks he can make it add up.