Former national security adviser Michael Flynn pleaded guilty Friday to one count of making false statements to the FBI and has agreed to cooperate with special counsel Robert S. Mueller III. White House lawyer Ty Cobb issued a statement saying that “nothing about the guilty plea or the charge implicates anyone other than Mr. Flynn.”

Cobb is engaging in some legal sleight of hand. The plea deal is most noteworthy not for the charges to which Flynn pleaded guilty, but for the charges it didn’t include. Given Mueller’s long-running investigation into Flynn and the allegations that have besieged him for months, the former Trump aide appeared to be in serious legal jeopardy. That he has managed to escape with barely a slap on the wrist in exchange for his cooperation with law enforcement suggests just how much he could tell authorities about other senior Trump administration and campaign officials.

False statements violations are the bread and butter of criminal investigations, and it’s common for defendants to be charged with them. (Pro tip from a former FBI agent: Guilty people lie.) Relative to most federal crimes, however, a single count of false statements carries a fairly light penalty of five years in prison. That’s why it often forms only one of many charges against a defendant — so that the penalty can be combined with those of other offenses, lengthening the potential sentence the accused could face.

Just based on what’s been publicly reported — without the benefit of knowing what else Mueller’s investigators have turned up — Flynn appeared to be on the hook for a laundry list of potential offenses. For one thing, last March, he retroactively registered as a foreign agent for the government of Turkey, as required by the Foreign Agent Registration Act (FARA). This is an indication that Mueller could have charged Flynn with knowingly violating FARA up to that point — a charge that the special counsel has brought against former Trump campaign chairman Paul Manafort and that also carries a five-year penalty. Flynn also was alleged to have been plotting in December 2016 to kidnap a Turkish opposition leader on U.S. soil and deliver him to Turkey in exchange for $15 million, a federal felony that could result in up to 20 years in prison. Finally, Flynn could have lied more than once to the FBI agents who interviewed him, offering the potential for additional counts of making false statements.

That means Mueller may have had enough evidence to charge Flynn with enough crimes to send him to prison for 30 years or more. Instead, Flynn has been charged with a single false statement count and — here’s the kicker — his plea agreement states that he will receive no more than six months of prison time for that. That’s an extraordinary sweetheart deal (even for the single charge). And it’s not one any prosecutor, especially one with an investigation as high-profile as Mueller’s, would make lightly. Mueller would offer this kind of a deal only if he could get testimony that helps his case, and if that testimony allows him to go higher up the chain.

There aren’t many targets that are higher than the national security adviser — which leads to President Trump’s inner circle, and Trump himself.

Lying to the FBI is bad, but Michael Flynn was accused of worse. Post editorial writer Quinta Jurecic on what she thinks is behind his Russia probe guilty plea. (Adriana Usero, Kate Woodsome/The Washington Post)

A key piece of the statement of offense detailing the facts underlying Flynn’s charge shows that Flynn was directed to contact the Russians by “members of the Senior Transition Team,” influence their policy positions with regard to Russian sanctions and a United Nations resolution, and report back. (The Washington Post and other news outlets have reported that one such official was Jared Kushner, Trump’s son-in-law.) Flynn can identify any transition members who were actively, knowingly and covertly in communication with the Russian government (against the official position of then-President Barack Obama’s administration). Further, if Mueller determines that Trump knew that this was taking place (or was directing any part of it himself), the president’s repeated attempts to get former FBI director James B. Comey to drop the investigation on Flynn could no longer be dismissed as simply a misguided attempt to help a friend. When combined with Comey’s firing, that would look like a clear case of obstruction of justice.

Flynn holds the key, to use a phrase from Watergate, to “who knew what when” — and since knowledge is the hardest element to prove in any crime, Flynn’s firsthand accounts could be solid gold for Mueller.

Some former prosecutors argued Friday that defendants typically plead guilty to every crime they have committed, and that the sparse charge may mean Mueller does not have much more to bring against Flynn. This is unlikely: Mueller would be taking a huge political risk to bring a single charge unrelated to collusion against a top Trump official, giving fodder to those who believe his investigation is a witch hunt. Instead, Mueller could be “saving” charges not covered by the plea to file later if Flynn does not cooperate as agreed. Or Mueller could be testing the waters to see if Trump will pardon Flynn. If the president does, Mueller could defer prosecution of the serious crimes such as kidnapping (which would also be covered under state law) to state attorneys general, since presidential pardons cannot reach state convictions.

So if anyone inside the White House truly believes Cobb’s spin that the charge is no big deal for the Trump administration, they shouldn’t. Flynn was among the president’s top handful of advisers — making him a big fish who wouldn’t ordinarily get off the hook so easily, given his stature and the example he sets for others in the administration. The sight of Flynn walking away with a guarantee he’ll barely serve any prison time should make everyone there — including Trump — very nervous.

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