A less obvious question for Robert Mueller: Why can’t a sitting president be indicted?

House Democrats today likely will pursue a line of questioning with former special counsel Robert Mueller that will not bear fruit: They want to know whether he would have indicted Donald Trump for obstruction of justice if the latter were not president. Mueller will repeat what he said in his May 29 public appearance: “Charging the president with a crime was … not an option” because of a longstanding Department of Justice (DOJ) policy regarding the indictment of a sitting president.  

Democrats will lose in this exchange, because they won’t get the answer they seek and will seem to be pushing Mueller past his comfort zone. A variant on that question, however, might provide greater illumination.  

House Judiciary Committee members should question Mueller closely about the legal basis for the Justice Department prohibition on indicting a sitting president. This would serve to expose the surprisingly weak foundations of this policy, as well as to identify some of the more far-reaching implications of either abiding by or abandoning it. 

In his press conference, Mueller said the prohibition is constitutionally mandated, but he declined to comment on what the constitutional principle at work might be. His report on the Russia investigation gives only slightly more detail. It quotes approvingly from the second of two Office of Legal Counsel (OLC) memos addressing this question, to the effect that a criminal prosecution of a sitting president could interfere with the impeachment process and that it is therefore inconsistent with the separation of powers.  

Apart from this passing reference to separation of powers and constitutional principles, however, the DOJ memos mostly focus on pragmatic, not constitutional, considerations. Indeed, the memos explicitly reject the constitutional interpretation of this question, saying that “the plain terms of the [Impeachment] Clause do not impose such a general bar to indictment or criminal trial prior to impeachment and therefore do not, by themselves, preclude the criminal prosecution of a sitting President.” 

This exposes a potential mismatch between Mueller’s explanation for the DOJ policy and the bulk of the explanation offered in the two Justice Department memos. Today’s testimony presents an ideal moment to clarify the policy, and Mueller should not hesitate to answer because the issue is not specific to any particular administration.

What is at stake in the different legal approaches to this question Mueller might take? One critical point is whether it will be possible to preserve any criminal charges for later prosecution against Trump when he no longer is president. Even if Trump does not win reelection, by the time he leaves office the five-year statute of limitations will have run on some of the alleged instances of obstruction, and all the more so if he serves a second term.

Mueller’s position that the prohibition on indicting a sitting president is constitutionally mandated implies presidential immunity to prosecution, and that in turn suggests that the statute of limitations should be tolled during the period of Trump’s presidency. On the other hand, the position that the DOJ policy is based on mere prosecutorial practice implies that the president is not immune to prosecution and that existing prosecutors simply have chosen not to exercise their lawful discretion. The statute of limitations most likely would continue to run on that account, and prosecutors would have lost the opportunity to prosecute Trump for the older instances of obstruction if they continue to adhere to the DOJ policy.  

So which view of the policy is the right one? There are several obvious difficulties with Mueller’s claim that the principles at stake are constitutional in nature. First, as the later OLC memo itself argues, other federal officers are subject to impeachment, but no one maintains they are similarly immune to prosecution. Second, it is at least theoretically possible for a president to be indicted without being removed from office, as has been explicitly acknowledged in other countries, such as Brazil and Israel.  

Following conviction, a president might still have to be impeached to be removed from office. While a convicted president could not run the country effectively, there is no reason to suppose the Constitution forbids this result, as scholars have argued. Given that convicting a president of a crime does not entail removal, the provision of impeachment is at least analytically separate from the question of presidential immunity for criminal acts.

The pragmatic view of the policy against indictment of a sitting president is also problematic, however. On this view, the DOJ policy is not legally mandated, but an accommodation to the pressures on the president and the country’s need for a fully focused commander in chief. It would not constitute a blanket prohibition on indicting a sitting president and therefore would not entail a grant of prosecutorial immunity. On this view, federal obstruction statutes are fully enforceable, and it is therefore unclear why indicting a sitting president should be categorically prohibited.

A third position is sometimes mixed in with the first two, and this is that the mere existence of the OLC memos, regardless of the reasoning they contain, provides a legal basis for a prosecutor to refrain from indicting a sitting president. This position would echo President Obama’s treatment of George W. Bush-era contributors to torture, which he resolved by saying that anyone who had relied upon the (now withdrawn) OLC memos blessing the torture program would not face prosecution.  

Today’s hearings would render a great service by making clear that any such view of OLC memos is indefensible. A congressionally mandated statute must prevail over an advisory opinion of an executive branch agency if there is a conflict between the two. OLC opinions are not law; they are interpretations of law, interpretations that a federal prosecutor might feel compelled to ignore in certain circumstances.  

As Mueller should make clear, the best explanation for his decision not to indict the president of obstruction of justice is that as special counsel he regarded himself as bound to follow OLC guidance, not because he was statutorily or constitutionally obligated to do so. He might have taken a different course, however, and another federal prosecutor might yet.

When should a federal prosecutor ignore the standard advice regarding indicting a sitting president? The short answer is: when there is no other way to stop such a president from corruptly misusing the powers of his office to shield himself from accountability. Such a prosecutor might be bucking DOJ tradition, but what hangs in the balance ultimately might be more important for defending the rule of law.

Claire Finkelstein is the Algernon Biddle Professor of Law and Professor of Philosophy and the director of the Center for Ethics and the Rule of Law at the University of Pennsylvania. Follow her on Twitter @COFinkelstein.