Trump, Mueller and the Four Critical Questions

A president's testimony under oath might not only affect him, but also the office he occupies.

With James Comey in January 2017.

Photographer: Andrew Harrer/Getty Images

Special counsel Robert Mueller is reportedly seeking testimony from President Donald Trump, who recently said that “he would love to” testify and that he would do so under oath – though he needs to speak with his lawyers.

The qualification is important and wise. For any high-level public official, testimony under oath comes with serious risks. For the commander-in-chief, the risks are multiplied, not only because of the overriding importance of his office, but also because foolish steps, establishing precedents, could have long-term effects on future presidents as well.

Any effort to seek testimony from a sitting president immediately raises a host of legal questions, which are best approached with a firm commitment to neutrality: Put your judgments about any particular president to one side, and ask what principles you would embrace for all presidents. With that commitment in mind, and without making any judgments about where Mueller’s investigation is ultimately going, here are the key questions.

Is the president obligated to testify before the special counsel, or can he claim some kind of immunity?

That’s an easy one. He’s obligated.

Nothing in the Constitution disables a prosecutor from requesting testimony from a president, or from obtaining a subpoena, compelling his testimony. (Mueller has subpoena power.) To be sure, good lawyers, acting on a president’s behalf, will try hard to minimize the legal risks by asking for accommodations – most importantly, by avoiding testimony under oath and by requesting written rather than oral responses.

To protect their client, Trump’s lawyers might well argue that Mueller lacks a sufficient justification for oral testimony under oath. But whether or not they’re right, they are unlikely to have a lot of leverage. On those counts, Mueller can probably get what he wants.

If Mueller finds that the president has committed a crime (such as perjury or obstruction of justice), can Trump be prosecuted?

Probably not.

It is true that in Jones v. Clinton, the Supreme Court allowed Paula Jones’s sexual harassment suit to go forward against President Bill Clinton. The court ruled that the Constitution creates no explicit barrier to civil suits, and it did not see a sufficient basis for finding an implicit barrier in the founding document.

But the justices would be unlikely to reach the same conclusion in the context of a criminal prosecution (and Mueller is investigating potential criminal violations).

Far more than a civil proceeding, such a prosecution would interfere with the president’s ability to do his job – to focus his time and energy on what he is supposed to do. Moreover, impeachment is the constitutionally specified mechanism for responding to egregious wrongdoing on the president’s part, at least while he is serving. A criminal prosecution would unsettle the constitutional plan.

If Mueller finds that the president commits a crime, can he be indicted, and then tried after he has left office?

That’s harder.

Standing by itself, a mere indictment need not unduly interfere with the president’s ability to do his job, so long as he doesn’t have to face trial. On the other hand, a case during the Nixon era can easily be read to suggest that so long as official acts are involved, the president has immunity from lawsuits of any kind.

The case involved Nixon’s allegedly unlawful dismissal of an Air Force employee; the employee sought damages. The court ruled that absolute immunity for damage actions, based on official acts, is “a functionally mandated incident of the President's unique office, rooted in the constitutional tradition of the separation of powers and supported by our history.”

An indictment is not a civil damage action, to be sure, but the Constitution seems to indicate that impeachment is the proper way to “indict” a president who is in office – which means that criminal indictments are forbidden.

If Mueller finds that the president committed a crime, such as perjury or obstruction of justice, can he be impeached?

Not necessarily! Speaking hypothetically: We need to know the details of what he perjured himself about -- or what, exactly, he obstructed.

The Constitution allows impeachment for “high crimes and misdemeanors.” In a nutshell, that phrase refers to egregious abuses of presidential authority. A crime is not necessary for impeachment – and it’s also not sufficient.

If a president perjures himself with respect to his business income or his relationship with a porn star, he’s not impeachable. He can’t be impeached if he obstructs justice with respect to an investigation into his best friend’s alleged shoplifting. (True, Bill Clinton was impeached for perjury and obstruction of justice growing out of his relationship with Monica Lewinsky; but that impeachment was a patent violation of the Constitution.)

On some subjects, however, perjury or obstruction of justice could turn out to be impeachable. We shouldn’t get ahead of ourselves, but reportedly Mueller is interested in whether the president obstructed justice by firing then FBI Director James Comey. If he did, that would be a grave matter: It would involve the unlawful use of presidential authority so as to interfere with a legitimate investigation into Russia’s role in the 2016 presidential campaign.  

Trump has said that he is “looking forward to” speaking with Mueller, but his lawyers are undoubtedly concerned. Their job is to protect him and the office that he occupies. For any president, testimony under oath might turn out to go just fine – but it is fraught with peril.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

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