In the biggest Capitol riot case yet, 11 Oath Keepers stand charged of seditious conspiracy. The government faces steep challenges in proving them guilty of the hefty and rare charges.

Transcript

STEVE INSKEEP, HOST:

Next, we report on 11 members of the Oath Keepers extremist group who are accused of attacking the Capitol. They are accused of seditious conspiracy, a criminal charge the government has rarely used. NPR justice correspondent Ryan Lucas has the law's history.

RYAN LUCAS, BYLINE: Even on its face, seditious conspiracy sounds bad. Federal code defines it as two or more people conspiring to overthrow or destroy the government of the United States by force or to prevent or delay the execution of any U.S. law.

JOSHUA BRAVER: Its origins lie in the Civil War as kind of a method to prosecute, basically, secessionists.

LUCAS: Joshua Braver is a law professor at the University of Wisconsin.

BRAVER: The idea of being branded a traitor to your country of committing sedition stands out. It sends a certain political message.

LUCAS: The Justice Department has only charged seditious conspiracy a half dozen times or so in the past 40 years and with a mixed record of success. The last time it brought such a case was in 2010 against members of the far-right Hutaree militia in Michigan. Prosecutors accused the Hutaree of plotting to kill police officers, then bomb the funerals in order to start a civil war. The defense said not so.

WILLIAM SWOR: They were in the woods. They were training. They had no plan.

LUCAS: William Swor was the attorney for the lead defendant in the case.

SWOR: The Hutaree neither had the means nor made any attempt to move against government.

LUCAS: And that ended up being a key point. The Hutaree never actually took action. It was nothing more, the defense said, than hot talk. Ultimately, the judge dismissed the case after finding that there was insufficient evidence of a conspiracy. Barbara McQuade was the U.S. attorney in Detroit at the time. She says the case failed for several reasons but not because of any problem with the law.

BARBARA MCQUADE: There's sort of a gut reaction that comes with a charge of seditious conspiracy that this is something more than just garden-variety type of a crime. This is an attack on our country.

LUCAS: She says that sort of gut reaction was missing in the Hutaree case.

MCQUADE: I think one of the reasons that people sometimes find that that element is lacking is just the utter disbelief that we have, that there can be people who want to overthrow our government or things that they could possibly be successful.

LUCAS: Technically, it's not a requirement that conspirators do anything illegal in furtherance of their plot, but concrete action can certainly help the government make its case. Take the 1981 prosecution against members of the Puerto Rican nationalist group known as the FALN.

JEREMY MARGOLIS: They built and planted something like 128 or so bombs, killing a number of people, wounding scores of people, maiming many, including New York City police officers.

LUCAS: Jeremy Margolis was an assistant U.S. attorney at the time and one of the lead prosecutors at trial. The government's case was aided, he said, by the fact that the FALN released communiques claiming responsibility for the bombings and explaining why they had carried them out.

MARGOLIS: How often do you have somebody put a bomb in a New York restaurant, the Fruances Tavern, at lunchtime, killing four and wounding 56 and then planting a communique saying, free Puerto Rico - that's why we did this?

LUCAS: It was, he says, a textbook case of seditious conspiracy. And the government won the case. The defendants were found guilty and received lengthy prison sentences. As for the Capitol riot seditious conspiracy case, the Justice Department alleges that 11 members of the Oath Keepers spent months recruiting, training and conspiring to use force to prevent the transfer of presidential power to Joe Biden. Several of the defendants stormed the Capitol on January 6. Court papers say the group also had weapons stashed at a hotel in Virginia and a quick reaction force ready to ferry them into D.C. if things got messy downtown. McQuade, the former U.S. attorney in Detroit, says the evidence put forward in the indictment, including text messages the defendants allegedly sent each other planning their course of action, suggest a strong case for the government.

MCQUADE: It's very clear that the target is the United States government, that they were attempting to stop the transition of power. They say so themselves. And there they are right at the scene at the seat of government in the people's house.

LUCAS: Of course, it will be up to prosecutors to make the case in court and prove it beyond a reasonable doubt. For now, the defendants have pleaded not guilty and are fighting the charges. Ryan Lucas, NPR News, Washington. Transcript provided by NPR, Copyright NPR.