President Trump, speaking at the Salute to Our Armed Services Inaugural Ball on Jan. 20 in Washington. (Alex Brandon/AP)

Shortly before the 2016 presidential election, an interesting constitutional thought experiment emerged: If Hillary Clinton did deserve to be locked up, in the eloquent articulation of Donald Trump supporters, could she use the power of the presidential pardon on … herself?

On Nov. 8, the question became pointless, as we learned that Clinton would not have that authority or any power of the presidency. But it has reemerged of late, given the spate of news articles concerning alleged wrongdoings in the Trump campaign and administration. If Trump violated some law, could he pardon himself?

The short answer is that no one really knows. The longer answer is that the reasons he might want to are more complex than we might usually assume.

“We can all only speculate what would happen if the president tried to do it,” said Brian Kalt, professor of law at Michigan State University and author of the book “Constitutional Cliffhangers.” “We’re all just predicting what the court would do if it happened, but no one can be sure.”

The constitutional language governing pardons reads, “The President … shall have Power to Grant Reprieves and Pardons for Offenses against the United States, except in Cases of Impeachment.” That vagueness is part of the reason the boundaries of the authority would need to be interpreted by the courts in unusual cases, like the one at hand.

That said, Kalt’s got an opinion about what the Supreme Court would do if Trump (or any president) tried to give himself a pardon: They’d throw it out.

Kalt’s reasons are similarly rooted in interpretations of the language of the Constitution and the intent of its authors.

For example, a pardon is “inherently something that you get from someone else,” he argued. That’s not explicit in the constitutional language, but, then, other boundaries we understand for pardons aren’t either, such as our understanding that there need not be a criminal charge before a pardon. (The most famous example of this kind of pardon was offered by President Gerald Ford to his predecessor, Richard Nixon.)

P.S. Ruckman, professor of political science at Northern Illinois University and author of the blog Pardon Power agreed with this idea in an email. “Supreme Court jurisprudence has always assumed a dichotomy — the granter and the recipient,” he said — the implication being that one person can’t play both roles.

What’s more, “presidents are supposed to be limited,” Kalt said. “The president has all of this power, but he has a limited term. If he was able to pardon himself, that would project his power well past his term.”

Kalt also noted that there’s a theme in the law that no one can be the judge in his own case. He raised the question of whether the vice president — who serves as the president of the Senate — would preside over his own impeachment trial, which also takes place in the Senate.

“Most people would find it unimaginable that the Senate would allow the vice president to preside over his own impeachment,” he said. “The only basis they could have for not allowing him to is that there’s this principle that’s embedded into the law that literally goes without saying.” Which, of course, is his point about the self-pardon.

But that the Constitution doesn’t say he can’t do it is, itself, a strong argument for his being allowed to. Samuel Morison is an attorney who specializes in pardon law, having spent 13 years in the Office of the Pardon Attorney within the Department of Justice.

“My opinion is that in theory that he could,” Morison said. “But then he would be potentially subject to impeachment for doing that.” Morison’s rationale is simple: “There are no constraints defined in the Constitution itself that says he can’t do that.”

Impeachment itself is specifically carved out of the presidential pardon power within the Constitution, so if Trump were impeached, he’d have no counter to that action.

There’s another clearly articulated boundary in the pardon provision that’s important: It applies only to any federal laws. If Trump were to issue himself a pardon, that would cover only any violations of federal law. And that, Kalt notes, might open a can of worms: State attorneys general (like New York’s, who has been eager to investigate Trump since even before the president was elected) would see the pardon as a signal that their digging might pay off.

Although that logic makes sense, it’s certainly not the case that a pardon necessarily means that a law was broken. The pardon can be used as a protection against unwarranted investigations or prosecutions. When the Hillary Clinton question came up in late 2016, Kalt wrote an article arguing that President Barack Obama might pardon her simply to protect her from unfair prosecution in the event that she was targeted by her opponent.

There is also the question of whether Trump would even risk such a tricky maneuver. It depends upon how threatened he felt of course — either because of what he’d done or because of how he worried he might be targeted in the future.

It’s been considered before.

“The historical point that Nixon considered it, that his lawyer analyzed it and said that in his opinion, Nixon could, but Nixon decided not to,” Kalt said, “I think that historical point is interesting and important.” Even Nixon, whose willingness to push the boundaries of his power was certainly well established, considered and declined the idea.

If Trump were to pardon himself, and if the courts were to sign off — ultimately meaning the Supreme Court, most likely — there’s not anything anyone could do about it. He’d be pardoned from prosecution for federal crimes under whatever limits he applied to his pardon, up until the point at which the pardon was granted.

If Trump really thinks the Russia investigation is an unfair witch hunt, that blanket of protection may prove remarkably alluring.