Paul Manafort arrives for a hearing at U.S. District Court...

Paul Manafort arrives for a hearing at U.S. District Court on June 15, 2018 in Washington, DC. Credit: AFP/Getty Images/MANDEL NGAN

The indictment of Paul Manafort by New York state prosecutors on Wednesday is a shot across the bow of the presidency — a warning and possible harbinger of future prosecutions of Donald Trump’s associates, children and even the man himself by the state.

Manhattan District Attorney Cyrus Vance Jr. made no bones about the purpose of the prosecution. In his news conference announcing the indictment, he said it was undertaken to make sure that Manafort, Trump’s former campaign chairman, would serve prison time even if the president were to pardon him of the federal charges to which he has now been convicted.

The timing was directly coordinated with Manafort’s second federal sentencing, in which a judge in Washington increased his prison time to seven-and-a-half years. That’s another indication that Vance wants to use the power of New York State to address a matter that has already been addressed by federal prosecutors.

Until now, there’s been lots of speculation about whether state officials would use criminal law to go where federal charges and investigations might not go, or where they might be thwarted.

The Manafort state indictment moves us from the realm of speculation to the realm of concrete reality. New York’s assault on the Trump presidency is underway.

Under ordinary circumstances, the prosecution of Manafort for, essentially, lying on his mortgage application, would be highly unusual.

It’s not that the crime is so minor. Confronted with explicit evidence of a significant and knowing lie on a mortgage application, New York prosecutors could easily have gone forward against a person of means who knew better.

Rather, as matter of conserving prosecutorial resources, it would be very strange for the district attorney’s office to bring charges against someone who was already convicted of federal offenses and set to spend meaningful time in prison.

State and federal prosecutors sometimes coordinate their efforts, as when the federal government controversially agreed to drop its indictment against the billionaire Jeffrey Epstein in exchange for his agreement to plead guilty in Florida state court to soliciting prostitution from a minor.

And sometimes federal prosecutors will effectively take a case away from their state counterparts by bringing charges first or essentially superseding state charges. That’s long been a bone of contention between the Manhattan district attorney and the U.S. attorney for the Southern District of New York, both high-prestige offices that compete to prosecute high-profile crimes in Manhattan.

The Manafort indictment in Manhattan is something different. It’s a self-conscious effort to bring a prosecution that would be outside of the reach of the Trump administration to thwart.

At an individual level, only Manafort will be affected by this extra prosecution.

At a symbolic level, the prosecution is all about Trump and his circle. It is surely intended to send a message to all the president’s men and women.

The core message is that Vance and his prosecutors have them in their sights. If New York can prosecute Manafort, why not Eric Trump or Donald Trump Jr., assuming state prosecutors have evidence of criminal conduct on their part?

Special counsel Robert Mueller, who is investigating Russian interference in the 2016 campaign, may well make or have already made a strategic decision not to prosecute Trump’s children. It’s easy to see why that would be reasonable for him. He might not want to appear vindictive. Or he might not want to provoke Trump to fire him, or to issue pardons for a raft of Mueller targets at the same time as pardoning Trump’s kids.

Vance has no similar strategic interests. He can act against people in Trump’s inner circle without fear of being fired or thwarted by pardons. And voters in Manhattan are unlikely to punish him for taking on Trump.

That leads us to the really big question implicated by the Manafort prosecution: Would Vance go after Trump himself?

Department of Justice guidelines now say that the president can’t be indicted while in office. Those guidelines don’t apply to state prosecutions.

Imagine, then, that Mueller’s report contains evidence of criminal conduct by Trump that took place in New York and can be reached by New York law — and that nothing happens after the report is issued.

Or consider that former Trump lawyer Michael Cohen has already twice testified under oath that Trump instructed him to commit federal election law crimes by paying off Stormy Daniels and hiding the source of the payment. It’s not completely clear that there was a state crime involved in that act, but perhaps one could be dreamt up, for example involving lies Cohen told in the course of getting and spending the money.

In principle, Vance could try to bring criminal charges against Trump even while he’s in office. There’s no legal precedent explicitly prohibiting him from doing so. And there are hints that such a charge might be able to go forward. The U.S. Supreme Court held that Bill Clinton could be subject to a federal civil lawsuit while he was president because no one is above the law. Following that precedent, New York courts have so far allowed civil cases against Trump to go forward: a defamation suit by “Apprentice” contestant Summer Zervos and an investigation into the Trump Foundation by the New York attorney general.

Ultimately, it seems probable that the U.S. Supreme Court would say that a president shouldn’t be charged even with a state crime while in office, because it would give state prosecutors the ability to shut down the presidency. But Trump would have to go through a legal process of appealing to various courts to get to that result. In the meantime, Vance would have made his point.

Alternatively and less radically, Vance might simply wait until Trump is out of office, then bring state charges. If Trump were replaced and pardoned by a sympathetic Republican president, that wouldn’t stop Vance. If Trump were followed by a Democratic president who declined to bring federal charges, for fear of setting bad precedent, that wouldn’t stop Vance either.

That’s the ultimate meaning of the Manafort prosecution. The odds of Donald Trump being prosecuted in some criminal court someday just went up.

Noah Feldman is a Bloomberg Opinion columnist. He is a professor of law at Harvard University and was a clerk to U.S. Supreme Court Justice David Souter. His books include “The Three Lives of James Madison: Genius, Partisan, President.”

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