Justice Department policy and two internal memos—one dating back to Watergate and the other from the Clinton era—suggest that the answer is no. This view is contested by various scholars, and most recently Sen. Richard Blumenthal (D-Conn.), who believes a president could be indicted and the trial postponed until after the president leaves office. Who is right?

Let’s start with the common ground. All agree that impeachment—which, if successful, turns a sitting president into an indictable ex-president—resolves the issue. But impeachment is highly unlikely in current circumstances, given that it requires a 2/3 vote in the Senate to convict. It is unimaginable that Republicans, who have tightly yoked their party to Trump, will be willing to impeach, and so the question of whether a sitting president can be indicted remains live.

Another point of agreement is that functional concerns matter. The president has a day job, and there is some risk that extensive involvement in court proceedings would interfere with his ability to carry out his constitutional functions. This was one of the arguments put forward in 1997 by then-president Bill Clinton in seeking the dismissal or postponement of the lawsuit brought by Paula Jones, in which she claimed he sexually harassed her when Clinton was governor of Arkansas. The Supreme Court’s 1997 decision in Clinton v. Jones rejected the argument for immunity or postponement, and decided that a sitting president could be sued civilly. The Court, however, did not resolve the question of whether he could be subject to criminal prosecution. The case held that the distraction involved in a civil suit was not so great as to impinge on the president’s carrying out his constitutional duty—an argument that turned out to be spectacularly wrong: It was the fallout from the civil suit that led to Clinton’s impeachment.

There is delicious irony in Trump relying on Clinton-era precedents to argue for immunity from process, but some of the language in Jones v. Clinton is not very helpful to Trump. The Court emphasized that the president “is subject to the same laws that apply to all citizens, that no case had been found in which an official was granted immunity from suit for his unofficial acts, and that the rationale for official immunity is inapposite where only personal, private conduct by a President is at issue.” Trump himself has been subjected to dozens of civil lawsuits since taking office. If he engaged in criminal behavior before taking office—involving campaign finance, or conspiracy to commit a crime, for instance—the logic of the opinion is that he would be subject to the same laws as the rest of us.

There is, however, the question of who could indict a president. Normally, the Department of Justice policies bind special prosecutors, and so Mueller would be unable to indict, absent a waiver from his superiors, in this case Rod Rosenstein. The independent counsel who prosecuted Clinton, Kenneth Starr, obtained a memo arguing that the independent prosecutor could indict a sitting president, but that special prosecutors could not because they are under presidential authority at the Department of Justice.

There is another group of prosecutors, however, who are not subject to Department of Justice policy: those in the states. There is nothing in the constitutional text that immunizes the president from state prosecutions. Nor, as the Jones case makes clear, is there immunity for unofficial acts of the president. If armed with evidence of violations of state law, the president would be “subject to the same laws that apply to all citizens.”

Here’s where the special prosecutor comes in. Even if he does not believe he can indict the president without approval from the Department of Justice, there is the possibility that the special prosecutor could legally release information that would lead to a state prosecution of the president. The Watergate prosecutor, Leon Jaworski, decided to name Richard Nixon as an unindicted co-conspirator for the Watergate break-in, rather than prosecuting directly. This led to impeachment proceedings and Nixon’s resignation, followed by a full pardon by Gerald Ford. Since conspiracies involve all of their participants in the crimes of any one of them, a federal prosecution of one of Trump’s associates for, say, wire fraud might lead to evidence that could be used against him in state court. Stay tuned for the next episode.

Tom Ginsburg is Leo Spitz Professor of International Law at the University of Chicago Law School and co-author with Aziz Huq of the forthcoming How to Save a Constitutional Democracy (The University of Chicago Press).