Attorney General Jeff Sessions has been implementing big changes at the Justice Department. Here's what you need to know about the former senator and early President Trump supporter. (Thomas Johnson/The Washington Post)

Attorney General Jeff Sessions recused himself from the Russia investigation. “During the course of the last several weeks, I have met with the relevant senior career Department officials to discuss whether I should recuse myself from any matters arising from the campaigns for president of the United States,” he said in his written recusal released on March 2. “Having concluded those meetings today, I have decided to recuse myself from any existing or future investigations of any matters related in any way to the campaigns for President of the United States.”

Any existing or future investigations. Related in any way.

Sessions consulted with the president and coordinated the firing of James Comey. Recall that Comey had testified on March 20 that he was heading the Russia investigation:

I’ve been authorized by the Department of Justice to confirm that the FBI, as part of our counterintelligence mission, is investigating the Russian government’s efforts to interfere in the 2016 presidential election. That includes investigating the nature of any links between individuals associated with the Trump campaign and the Russian government, and whether there was any coordination between the campaign and Russia’s efforts. As with any counterintelligence investigation, this will also include an assessment of whether any crimes were committed. Because it is an open, ongoing investigation, and is classified, I cannot say more about what we are doing and whose conduct we are examining.

That is the investigation that Sessions promised to stay away from. Firing the man heading the investigation — especially if Sessions knew that the reason was not the one stated in Deputy Attorney General Rod J. Rosenstein’s May 9 memo — is a matter “arising from the campaigns for President of the United States.”

Sessions may have some explanation for why he chose to participate in the firing of Comey. But the attorney general may now be in considerable legal peril.

The Washington Post's Ruth Marcus explains how FBI Director James Comey's firing is a big deal, yet not quite "Nixonian." (Adriana Usero/The Washington Post)

Refusing to recuse oneself from a conflict or breaking the promise to recuse from a conflict is a serious breach of legal ethics. “Someone could file a bar complaint, and/or one with DOJ’s office of professional responsibility, if Sessions had a conflict of interest when it came to the firing decision, and  if he did not follow the ethics rules, including those of DOJ by acting when he had a conflict of interest,” legal ethics expert Norman Eisen tells me. “The fact that he broke his recusal commitment, if he did, would be relevant context, and violating an agreement can sometimes in itself be an ethics violation.” In sum, Sessions has risked his law license, whether he realized it or not. He needs to testify immediately under oath; if there is no satisfactory explanation, he must resign. The alternative could be impeachment proceedings.

The problem for Sessions (as it is for Trump) is legal as well. This returns to whether firing Comey constituted obstruction of justice. Lawfare blog supplies us with the persuasive analysis:

Under 18 U.S.C. § 1505, a felony offense is committed by anyone who “corruptly, or by threats or force, or by any threatening letter or communication influences, obstructs, or impedes or endeavors to influence, obstruct, or impede the due and proper administration of the law under which any pending proceeding is being had before any department or agency of the United States, or the due and proper exercise of the power of inquiry under which any inquiry or investigation in being had by either House, or any committee of either House or any joint committee of the Congress.”

An accompanying code section, 18 U.S.C. § 1515(b), defines “corruptly” as “acting with an improper purpose, personally or by influencing another, including making a false or misleading statement, or withholding, concealing, altering, or destroying a document or other information” (emphasis added). This is where obstruction of justice intersects with the false statements law. If you knowingly and willfully make a false statement of material fact in a federal government proceeding, you’ve potentially violated § 1001, and when you add an objective to influence, obstruct, or impede an investigation, you’ve now possibly violated § 1505 as well. Perjury can intersect with obstruction of justice in the same way.

Under the statute, a “proceeding” can be an investigation. Section 1503 criminalizes the same conduct in judicial proceedings. So obstruction during an investigation might violate § 1505, while if that same investigation leads to a criminal prosecution, obstruction during the prosecution itself would violate § 1503. The individual also has to know that a proceeding is happening in order to violate the statute, and must have the intent to obstruct—that is, act with the purpose of obstructing, even if they don’t succeed.

The question for Sessions — and for the president — is whether there was intent to obstruct justice. (“As applied to the President and his staff, the first two elements appear to be a slam dunk. First, courts have given “proceeding” a broad definition. … Second, Comey himself had recently confirmed that the investigation was ongoing—in extremely public and publicized congressional hearings.”) That leaves the matter of intent.

While ordinarily one might find this hard to prove, here we have overwhelming evidence that the reason for the firing was not his handling of the Hillary Clinton email matter. Saying it was not about Russia constitutes a lie, part of an effort to interfere with the investigation. Firing the lead investigator to slow the investigation appears to be designed “to influence, obstruct, or impede the due and proper administration of the law under which any pending proceeding.”

So Sessions faces a host of serious, potentially career-ending questions. “As I see it, the President’s discharge of FBI Director Comey on a clearly pretextual basis for the obvious purpose (even if unlikely to be achieved) of shutting down the FBI’s then-accelerating investigation into possible collusion between the Trump campaign and Russia was on its face an obstruction of justice, the very same charge that the first Article of Impeachment against Richard Nixon made,” says constitutional law expert Laurence Tribe. “And part of the evidence supporting the charge of AG Sessions’ conscious involvement in that obstruction is the way in which he violated his public recusal commitment, something he cannot possibly have done in a fit of absent-mindedness.”

We are open to alternative explanations for Sessions’s conduct, but what could they possibly be?