If Michael Cohen goes down, could Donald Trump save him?

Trump’s “fix-it guy” is at the center of a major FBI investigation, with agents searching Cohen’s office, home, and hotel room under the direction of the US attorney’s office for the Southern District of New York, who received a “referral” from special counsel Robert Mueller.

The raid took place in connection to Cohen’s role in allegedly arranging hush money payments to two women who reportedly slept with Trump, and a potential effort to stop the release of the infamous Access Hollywood “grab ’em by the pussy” tape. Meanwhile, special counsel Robert Mueller is also investigating the Trump Organization’s business deals overseas, including deals Cohen was involved in, and is also reportedly interested in a donation Cohen solicited from a Ukrainian oligarch.

And then there’s the matter of Cohen’s own finances, also under investigation by the FBI. In addition to ties to Ukrainian oligarchs stemming from a mid-2000s ethanol company he co-owned, Cohen holds dozens of New York City taxi medallions, the expensive permits required to operate taxis in the city. As of April 2018, he owes the state of New York $53,836 in unpaid taxi taxes.

If Cohen were to be charged with any crimes connected to these various allegations, he could find himself in court facing a prison sentence. There’s speculation that Mueller might use that pressure to try to flip him to help him in his probe of the Trump campaign’s ties to Russia.

But Cohen has thus far been unfailingly loyal to Donald Trump and the Trump family, reportedly telling a radio host Wednesday, “I’d rather jump out of a building than turn on Donald Trump.” He even keeps bobbleheads of Trump’s sons Eric and Donald Jr. on his office desk.

So there’s also another possibility: Trump could try to grant Cohen a presidential pardon before Cohen even considers a plea deal with Mueller. But that would only get Cohen out of jeopardy in federal court. He could still end up in prison if he’s tried or convicted on state charges.

Pardons only work for federal crimes, not state crimes

First, a quick primer on presidential pardons. Article II, Section 2, Clause 1 of the Constitution reads in part: “[The president] shall have Power to grant Reprieves and Pardons for Offenses against the United States, except in Cases of Impeachment.” That gives the president of the United States the power to pardon people convicted of federal crimes through “executive clemency.” So Trump absolutely could pardon any of his associates accused, charged, or convicted of a federal crime, including Cohen.

State and federal crimes are different. A state crime, which might include robbery, burglary, or aggravated assault, breaks state law (most crimes committed are state crimes). Federal crimes, in comparison, are ones that violate US federal legislation, and are prosecuted by a US attorney. Examples of federal crimes include mail fraud or organized crime. But some crimes violate state and federal law — for example, someone can commit a murder (state crime) that also violates federal hate crimes law (federal crime).

In the Cohen case, it appears that he’s currently under investigation for violations of federal law — specifically, bank fraud, wire fraud, and campaign finance violations. But bank fraud is also a state crime, meaning that Cohen could be prosecuted on that charge by a New York district attorney, though it’s not currently clear what the theory behind the bank fraud allegations is.

(While the Constitution prohibits double jeopardy, or prosecuting someone twice for the same crime, there is nothing stopping state and federal agencies from bringing similar criminal charges against someone based on the same criminal act — the “separate sovereigns” doctrine.)

I asked Keith Whittington, a politics professor at Princeton University, whether Cohen could be pardoned by President Trump for any federal charges but still brought to trial on state charges.

“It could easily happen if there are several different actions that were legally problematic,” Whittington told me, “but it could also happen even if the same action (or related set of actions) violated both federal and state law. Just to take a high-profile, but very different, case — Dylann Roof was charged with both federal and state crimes resulting from his shootings at the Emanuel African Methodist Episcopal Church in Charleston.”

Judith Miller, an associate professor of law at the University of Chicago Law School, also referenced the Roof case when we spoke, telling me that Roof was convicted on federal hate crimes charges in federal court and sentenced to death, and pleaded guilty to murder charges in South Carolina state court, where he was sentenced to multiple life sentences.

“All the charges arose out of the same events, but both South Carolina and the federal government prosecuted him,” she said. “The charges weren’t brought as a mix of charges in one case, though. The state filed its charges, and the federal government filed separate charges.”

Only federal prosecutors can charge defendants with federal crimes, and only state prosecutors can charge defendants with state crimes. Typically, when someone is charged with crimes by both the federal government and state prosecutors, the federal government will usually stand down and let the state government try their case first, said Barbara McQuade, a professor at the University of Michigan Law School and former US attorney for the Eastern District of Michigan. (Not always — in the Roof case, the federal government went first.)

One example is the trials of four Los Angeles police officers who beat taxi driver Rodney King while arresting him on March 3, 1991. After a Los Angeles jury acquitted three of the four officers on charges of use of excessive forces, the Department of Justice indicted the four officers for violating King’s civil rights. That trial resulted in two convictions and two acquittals.

Cohen could face several New York-based charges — and there’s nothing Trump could do about it

The investigations into Cohen are ongoing, and he hasn’t yet been charged with any crime. But Sonja Starr, also of the University of Michigan Law School, said that the investigators are looking into several issues that would be prosecuted at the state level rather than the federal level.

The investigations could lead to charges of bank fraud, money laundering, and threats of violence — all state crimes. If Cohen is charged with violating campaign finance laws in his payment to Stormy Daniels, on the other hand, that would be a federal crime.

“The fact pattern in this case certainly suggests that various state charges are possible,” she said, “in New York [in addition to] any other states where criminal conduct took place.”

If Cohen were to face state charges, only the governor of New York could pardon him. And that’s not Trump — that’s Andrew Cuomo, who earlier this year threatened to sue the president over the Republican tax bill.

In short, Michael Cohen’s legal problems go way beyond Robert Mueller’s investigation.