Alan M. Dershowitz, revered Harvard Law professor and expert in constitutional and criminal law, aired a controversial legal defense for former national security adviser Michael Flynn on Monday, arguing via Twitter that lying to the Federal Bureau of Investigation isn't a crime unless that lie is “material.”

Dershowitz's outburst has received widespread criticism and came after Robert Mueller, special counsel in the investigation into Russian election meddling, released an FBI memo describing a January 2017 interview with Flynn.

Michael Flynn. Photo: Diego M. Radzinschi/ALM.

The memo details what Flynn told investigators about his contact with then-Russian ambassador to the U.S., Sergey Kislyak in the run-up to the 2016 presidential election. The FBI believed Flynn had discussed potential foreign policy changes with Kislyak, but Flynn characterized their encounters as inconsequential.

In December 2017, Flynn pleaded guilty to lying about conversations with Kislyak in that interview and later signed a plea deal. His sentencing was scheduled for Tuesday, but federal judge Emmet Sullivan in the District of Columbia postponed it.

In a long string of tweets, Dershowitz theorized that what Flynn lied about wasn't material to the case as it was information the FBI already knew. That, according to Dershowitz, meant Flynn might not have committed a crime.

Dershowitz also claimed FBI agents set Flynn up to lie.

“When the FBI already has a recording of a meeting, and asks whether that meeting occurred, a false answer is not material to the investigation. The only reason to ask that question is to test the witness, not to learn information. Morality tests are not the proper role of the FBI,” Dershowitz tweeted.

What did he mean? Has Dershowitz lost his marbles, or has he put forward a valid point? Here's what South Florida criminal law experts make of it.

David S. Weinstein, partner with Hinshaw & Culbertson in Miami. courtesy photo.

According to white collar criminal defense lawyer David S. Weinstein of Hinshaw & Culbertson in Miami — who served as assistant U.S. attorney for the Southern District of Florida for more than 10 years — the answer lies in 18 U.S. Code 1001, the federal statute that governs false statements.

“A lie is always a lie, whether you make it to the FBI, whether you make it to your mother, whether you're telling it to somebody you know or don't know,” Weinstein said. “When it becomes a crime is when you're obstructing and making a false statement to a law enforcement officer or somebody involved in the judicial system.”

While it's clear that Flynn lied, to be guilty of a 1001 violation, he had to “knowingly and willingly” lie to an FBI agent about something material to an ongoing investigation.

The way Weinstein sees it, he did. But the argument could have legs in other cases.

“If your statement is, 'I saw a John Doe and John was wearing a green coat,' but it turns out that John Doe was wearing a red coat, and the fact that it was a red coat wasn't material to the ongoing investigation because it didn't lead to the identity of a suspect and some crime or something else, then you've told a lie to law enforcement but it's not a material lie.”

According to Weinstein, Flynn's alleged crime is among the hardest to get a jury to decide on as it requires careful instruction about what “material” means.

Academia versus 'Practical Reality'

Richard Serafini of Serafini Law Offices in Fort Lauderdale. Courtesy photo.

White-collar defense attorney Richard A. Serafini of Serafini Law Offices in Fort Lauderdale doesn't buy what Dershowitz is selling as he's ignored the “willful and knowledgeable” part of Code 1001 to create a new and very restrictive definition of materiality.

“He's on an island by himself on this one, I think,” Serafini said. “You can easily go to any number of sources for a legal definition of materiality, and I don't think you'll find any that says something ceases to be material once an investigating authority or an opposing party knows the fact.”

Serafini, who's spent more than 20 years working fraud cases for the state and federal government, suspects there's no case law to support Dershowitz's definition of “material,” although it might make an interesting Law Review article.

“But I don't think he's going to persuade any judges,” Serafini said.”Flynn met with the FBI, he knowingly and willfully provided false information on material facts of the investigation and he pleaded guilty.”

Judge Emmet Sullivan. Courtesy photo.

Related story: Don't Assume Anything From Your Sentencing Judge, and Other Takeaways: Flynn Edition

Former federal criminal prosecutor Ryan O'Quinn of DLA Piper in Miami was incredulous when he saw the tweets, which he said potentially undermine Dershowitz's credibility.

“I don't understand how you would take the position that Flynn's lies on the specific subject matter that was the express purpose of the interview would not have been material to the interview,” O'Quinn said. “If it wasn't material, why was it being discussed?”

In O'Quinn's mind, Dershowitz's argument is a stretch and demonstrates the difference between academia and “practical reality.”

Dershowitz also hypothesized that the FBI tricked Flynn into talking to them without a lawyer — an argument his lawyers have also made. But the way Hinshaw & Culbertson's Weinstein sees it, Flynn almost certainly knew what he was getting into.

“This is not an average citizen,” Weinstein said. “This is somebody who has a very expansive military background and who's aware of what the rules and regulations are.”

According to Weinstein, FBI agents use that tactic all the time, and they do it because they believe people like to speak more freely without a lawyer being present.

“Did the agents use a tactic or technique to get him to talk to them without having an attorney present? Absolutely. Is there anything morally wrong with that? No,” Weinstein said.

'It's What We Do As Lawyers'

Though Weinstein doesn't see Dershowitz's point, he concedes there's nothing wrong with exploring it.

“It's what we do as lawyers. We split words, we try and dig down to make a distinction about what the words mean. That's what (Dershowitz) was trying to do,” Weinstein said.

The platform the famed professor chose, however, could have contributed to the backlash, according to Weinstein.

“He may not have done it in an artful manner that's easily digestible to the common person,” Weinstein said. “I understood exactly what he was saying as a lawyer, but that's because I'm a lawyer.”

According to Serafini, the whole thing was a tempest in a teapot.

“It got a lot of play because it was Dershowitz,” Serafini said. “A law professor that nobody had ever heard of would have gotten a lot less play.”