This piece was originally published on Just Security, an online forum for analysis of U.S. national security law and policy.

Earlier this week, President Donald Trump’s longtime personal lawyer and fixer Michael Cohen told a federal judge under penalty of perjury that he committed a felony “in coordination” and “at the direction of” a “candidate for federal office.” Though that candidate is unnamed, it is clear that Cohen was referring to the president of the United States. This raises the question of whether the president can be criminally prosecuted himself. The answer is: Yes, but it’s far from clear when or how.

To begin with, it’s important to note that it is highly unlikely that there will be a criminal trial in federal court during Trump’s presidency. The Department of Justice’s Office of Legal Counsel wrote a memo in 1973, reaffirmed in 2000, concluding that the president cannot constitutionally be subject to criminal indictment and prosecution during the time he is in office. Some commentators have described this opinion as a Justice Department “policy,” but it is far more than that. It is the OLC’s position on what the U.S. Constitution allows and forbids.

OLC opinions are binding on the Department of Justice and the rest of the executive branch. In theory, the current OLC could revisit that conclusion, but that is beyond unlikely. The OLC opinions thus likely tie special counsel Robert Mueller’s hands, along with all other executive branch attorneys. (Andrew Crespo has argued that Mueller may be free to ignore the opinions, and former White House counsel Bob Bauer agrees and adds that it is a question for the courts to decide. But most legal scholars take the view that Mueller is bound by the opinions and could not even test them in court.)

But that’s far from the end of the story. There are three alternative paths left open.

Pathway 1: federal indictment after a president leaves office

First, even if a sitting president is immune from criminal prosecution while in office, that does not apply after he leaves (or is removed from) office. The same Office of Legal Counsel opinions concluding that presidents are not subject to criminal prosecution when in office, emphasize the availability of criminal prosecution after the president has left office.

Now one problem here is that for some charges, the statute of limitations might run. The default statute of limitations for federal offences is 5 years, but for some relevant charges it is shorter. This raises the possibility that the president could run out the clock. (For a helpful discussion of the statute of limitations issues, see this summary of a panel of experts.) To address this problem, the 2000 OLC opinion suggests judges might toll the time to file while the president is immune.

That same OLC opinion (in footnote 38) cuts off what would otherwise have been another possible alternative for Mueller: Indicting the president under seal, which would keep the indictment confidential, and then staying it until the president leaves office. That would prevent the president from using his office to evade criminal charges altogether, but allow him to continue with his responsibilities unimpeded while in office. The OLC opinion does not offer much explanation before concluding that this approach would “take an unacceptable gamble with fundamental constitutional values.”

Pathway 2: federal indictment naming sitting president as unindicted co-conspirator

Second, Mueller might identify Trump as an “unindicted coconspirator,” as Ryan Goodman has explained. This was the approach the special prosecutor took in Watergate. The grand jury named President Richard Nixon as an unindicted co-conspirator when it issued its indictments. But as Ryan notes, post-Watergate rules counsel against this approach, though they don’t prohibit it. This approach would not result in criminal penalties for the president, but it could strengthen the case for impeachment and conviction by the Senate—as it did in Nixon’s case, leading the president to resign.

As an aside: Another option that has similar functions and effects to naming the president as an unindicted coconspirator is “presentment.” This procedure would allow the grand jury to say that there is probable cause to believe the president committed a crime and that the jury would have indicted him were he not immune as a sitting president. This procedure is highly unusual, to say the least, and should be considered a wildcard.

Pathway 3: state indictment of a sitting president

There is a third way forward: A state attorney general could decide to indict. The OLC opinions are binding only within the executive branch. They do not bind state attorneys general. If a case went forward, then it would be up to the courts to decide whether the president is immune from criminal prosecution. (And even if the courts did not allow a case to go forward during Trump’s presidency, they could allow an indictment under seal, plus a stay, to avoid the statute of limitations problem.) Indeed, New York investigators just subpoenaed Cohen as part of their Trump Foundation probe. That is not good news for Trump. (An added bonus: State-level charges are not subject to presidential pardon.)

Would the courts allow the case to proceed? That’s a hard call. Nixon v. Fitzgerald and Clinton v. Jones both were about civil, not criminal, suits (and in the case of Nixon, it related to liability predicated on the president’s official acts). Ryan Goodman has put forward a persuasive reading of Nixon that suggests that it could support a criminal case against the president even while still in office. Both Nixon v. Fitzgerald and Clinton v. Jones endorse an approach in which the courts “balance the constitutional weight of the interest to be served against the dangers of intrusion on the authority and functions of the Executive Branch.” In Nixon, the court decided the imposition was too great, and in Clinton, it decided it was not. What could happen in a case against Trump therefore turns on the court’s judgment of whether the public interest in timely criminal prosecution outweighs the importance of allowing the president to carry out his responsibilities without the interference a criminal case would present. (The potential for a plethora of state prosecutions could weigh on the judges’ minds, as well.)

Guilt or innocence

None of this answers the question of whether the president would be found guilty if a case against him goes forward. As former White House counsel Bob Bauer recently observed, the kinds of hush money payments at issue here “can present tricky issues of motive.” He points out that a similar case against John Edwards—for concealing an affair and the child it produced and making covert arrangements for his mistress’s and child’s support—did not result in conviction. But Cohen’s plea—and the statements accompanying it—makes this a stronger case than was the case against Edwards. (Paul Seamus Ryan shows why the case against Trump would avoid many of the weaknesses prosecutors faced in the Edward’s case.)

The political remedy: impeachment

Finally, on the question of impeachment, I remain a skeptic, though less so than I was at the beginning of this week. Impeachment in the House becomes more likely after the midterms if the Democrats regain control of the chamber. But conviction in the Senate remains highly unlikely. Even if the Democrats retake the Senate, the majority will be slim, and it takes two-thirds of the Senate to convict. Even if there is ample evidence to convict, Republicans would have to really turn a corner to be willing to vote to remove Trump from office. I doubt whether even Democrats will be eager to convict. Would Democrats rather face a discredited and wounded President Trump for re-election in 2020 or a President Pence, who has managed to remain largely out of the fray to date? The safe bet, for the moment, is that the Trump presidency is unlikely to become the first one to be ended by conviction in an impeachment trial.

Of course, looming impeachment and possible conviction might force the president to resign, as did Nixon—especially if he thought Pence might issue a pardon. But Trump has shown no signs of surrendering, and he appears to care less for the norms of democratic governance and institutions of American government than did Nixon. This president seems to revel in spectacle; the chances that he would step aside to avoid it look—for the moment—slim.

If Trump is going to face consequences for his actions, it is most likely to come from the ballot box in the 2020 election and in a courtroom soon thereafter.

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