WASHINGTON - Five members of the Oath Keepers group, including leader Stewart Rhodes, face trial for seditious conspiracy next week, in which U.S. prosecutors will try to convince jurors that Rhodes's call for an armed "civil war" to keep Donald Trump in power on Jan. 6, 2021, was literal - and criminal.

Starting with jury selection Tuesday and opening statements as early as Thursday, Rhodes's trial could reveal new information about the quest to subvert the 2020 presidential election results, as prosecutors continue to probe Trump's conduct and that of his inner circle.

Prosecutors' challenge will be to prove that Rhodes, one of the most visible figures of the far-right anti-government movement, and his group intentionally conspired to use force to prevent President Biden's swearing-in. Whether the government tips its hand in court about the Oath Keepers' ties to other political figures, the trial is an important step in the wider probe, analysts said.

Investigators continue to ask cooperating members of the Oath Keepers who have pleaded guilty about their knowledge of any coordination with others, according to defense attorneys. And they would welcome cooperation from those on trial, even if it came after convictions and the prospect of prison, former prosecutors said.

"I don't think that the investigation is by any means over," said Barbara L. McQuade, a former federal prosecutor who teaches law at the University of Michigan. "I think they may have important lines of investigation, and we just don't know it yet. . . . and it will take many more months before they feel they have tapped all those veins of information."

Prosecutors plan to call as many as 40 witnesses over a projected five-week trial, draw from 800 statements by those charged and summarize tens of thousands of messages, hundreds of hours of video footage and hundreds of phone call, location and financial records, according to pretrial proceedings. Three Oath Keepers members have pleaded guilty to the seditious conspiracy charge and are among more than a dozen potential informants in the case, according to government filings.

In previous court proceedings, Rhodes and his co-defendants have said their actions were defensive, taken in anticipation of what they believed would be a lawful order from Trump deputizing militias under the Insurrection Act to stop Biden from becoming president. They are prepared to argue they relied on advice from their attorney, Oath Keepers general counsel Kellye SoRelle, to delete their communications when Trump did not act.

"What the Government contends was a conspiracy to oppose United States laws was actually lobbying and preparation for the President to utilize a United States law to take lawful action," Rhodes attorneys Phillip A. Linder and James Lee Bright argued.

Prosecutors said the Oath Keepers were using the Insurrection Act as legal cover for actions they were prepared to and did take, regardless of what Trump did. And even if those on trial sincerely believed Trump could have invoked the act, he never did, and lacked the authority to authorize a conspiracy to attack Congress or the presidential transition, prosecutors said.

A federal defender for SoRelle, who has been charged separately in the attack and pleaded not guilty, did not respond to a request for comment.

The trial also poses a test for the Justice Department as it confronts rising domestic extremism and politically motivated violence. Convictions for seditious conspiracy would deliver a public condemnation of political violence and could mark the end of the Oath Keepers as an organization, if not as a movement, extremism experts said. According to the National Consortium for the Study of Terrorism and Responses to Terrorism at the University of Maryland, about 35 percent of the more than 860 people federally charged in the Capitol riot were associated with extremist groups or conspiratorial movements.

Charging groups that see themselves as victims of government tyranny with seditious conspiracy is not without risk, senior consortium researcher Michael Jensen said.

If Rhodes and the Oath Keepers are found guilty, anti-government extremists could treat them as martyrs and use them to attract recruits. Acquittals would deliver a bigger boost, allowing private militant organizations to claim a victory over the government "enemy," he said. Still, successful prosecution could deter elected leaders and law enforcement officials from supporting radical anti-government groups that try to present a more moderate face to the mainstream public.

"While the Oath Keepers might struggle to keep going, the people supporting its causes are still there, and the ideas that motivated them are still there," Jensen said, adding, "This prosecution isn't going to end anti-government militias in the United States."

The trial is the first of three seditious conspiracy trials set this fall accusing members of the Oath Keepers and a second far-right group, the Proud Boys, of plotting to use force to oppose the lawful transition of power by attacking Congress as it met to confirm President Biden's 2020 election victory.

Prosecutors depict the Oath Keepers convergence that day on the East Capitol steps as a milestone, where political polarization tipped into plotting insurgency and violence. The Oath Keepers group came in combat-style tactical gear with an "arsenal" of weapons staged at nearby hotels, prosecutors have said. The Oath Keepers on trial are not charged with assaulting police, though the indictment describes them as joining mobs that fought with law enforcement.

The 44-page indictment against Rhodes and eight co-defendants is unusual in that it alleges a seditious conspiracy that came to fruition with an actual attack, and was not just "aspirational," legal analysts said. The nine indicted have been split into two trial groups, with Rhodes and four others going first and the rest in November.

"Defendants can use the argument, 'This was just tough talk, we're a group of blowhards who like to talk and make stuff up.' But when plans are written out in text messages and something actually comes to pass, it's much easier for the government to prove to a jury they intended to do it," McQuade said. "That's a real treasure trove that can be powerful evidence that someone has entered into an agreement, and that's what makes this case different from others."

The Justice Department failed the last time it brought such a case in 2010, when a federal judge dismissed seditious conspiracy charges against members of the self-described Hutaree militia in Michigan, citing a lack of proof that the group had firm plans to launch attacks. McQuade, then the U.S. attorney for eastern Michigan, defended the arrests at the time, saying investigators believed the group was on the verge of carrying out a deadly plot.

Rhodes, a Yale Law School graduate and former Army paratrooper and aide to libertarian congressman Ron Paul (R-Tex.), founded the Oath Keepers in 2009, saying its mission was to prevent "a full-blown totalitarian dictatorship" from arising in the United States. His group took off amid anti-government fervor after the election of President Barack Obama. It later aligned itself with Trump and promoted his claims of widespread voting fraud

Charging papers say Rhodes made a string of incriminating statements, starting two days after the 2020 election. On Nov. 5, Rhodes privately repeated to an invitation-only message group of Oath Keepers leaders: "We aren't getting through this without a civil war. Too late for that. Prepare your mind, body, spirit," according to his indictment. Five days later, Rhodes published a plan of action under the headline, "WHAT WE THE PEOPLE MUST DO." He cited the example of an anti-government uprising in Serbia that stormed parliament, prosecutors say.

That same day, Rhodes announced publicly on Alex Jones' Infowars web show that he had armed men stationed outside Washington "prepared to go in" to prevent Trump from being removed illegally from office, adding that he should declassify materials to expose the "deep state" and "who all the pedophiles are."

After Trump called supporters to Washington for a "wild" rally on Jan. 6, Rhodes honed his message. If Biden assumed the presidency, he told an Oath Keepers regional leader on Dec. 22, "We will have to do a bloody, massively bloody revolution against them," according to his indictment. In an open letter Dec. 23, Rhodes urged Trump to invoke the Insurrection Act if Congress certified the election, saying that on Jan. 6, "Tens of thousands of patriotic Americans, both veterans and nonveterans, will already be in Washington, D.C., and many of us will have our mission-critical gear stowed nearby just outside D.C." He said the group was ready to "take to arms in defense of our God given liberty."

Prosecutors are expected to present new testimony from cooperating witnesses. But it remains unclear whether they will expand on suggestions in court filings, public reports and congressional hearings of the defendants' ties to political figures.

Cooperating Oath Keepers defendant William Todd Wilson in April told a court that he heard Rhodes repeatedly implore someone over the phone the evening of Jan. 6 "to tell President Trump to call upon groups like the Oath Keepers to forcibly oppose a transfer of power," but whoever was on the other end denied Rhodes' request to speak with Trump directly. Earlier, SoRelle briefed Oath Keepers about efforts to overturn the election by representatives of the Trump campaign, the Republican National Committee, QAnon conspiracy supporters and the legal team of Rudy Giuliani, according to a transcript of a Nov. 9 GoToMeeting call released in another defendant's court filing this spring.

Florida and national leaders of the Oath Keepers were in contact with Proud Boys leaders and also with Trump political confidant Roger Stone and former Trump national security adviser adviser Michael Flynn, providing security around the latter two. Prosecutors have noted that Trump attorney Sidney Powell also has helped raise money through her nonprofit group for some of the Oath Keepers' legal defense.

Attorneys for Powell and Defending the Republic did not respond to requests for comment.

Prosecutors said Rhodes and at least 10 co-conspirators brought firearms, ammunition and related items to the Washington area - with Rhodes spending $40,000 on such gear just before and after Jan. 6. They staged the weapons across the Potomac River at a Ballston hotel with rooms assigned to armed "Quick Reaction Force" teams from North Carolina, Arizona and Florida, prosecutors said.

That day, charging papers say that Rhodes exchanged numerous calls with a deputy and directed co-defendants' movements outside the Capitol by text, then spoke with them before several breached the building. On the east side of the Capitol, prosecutors say, a "stack" of five Oath Keepers in tactical gear moved to the front of the mob attacking police outside the Rotunda doors and then forced their way inside, where some of them joined a group pushing against a police line at the hallway to the Senate chamber and searched in vain for House Speaker Nancy Pelosi (D-Calif.). A second "stack" of Oath Keepers, also in tactical gear, entered through the same doors about 30 minutes later, according to the indictment, and at least one battled with police near the Rotunda and was eventually repelled by officers using chemical spray.

Afterward, prosecutors alleged Rhodes said, "Patriots entering their own Capitol to send a message to the traitors is NOTHING compared to what's coming," and called for local extremist groups to organize to oppose the Biden administration.

Standing trial with Rhodes are Kelly Meggs, 53, an auto dealership manager from Dunnellon, Fla., who prosecutors described as the "Florida state lead" on Jan. 6; Kenneth Harrelson, 42, a medically discharged former Army sergeant and father of two from Titusville, Fla., who prosecutors called the "ground team lead"; Jessica Watkins, 39, another Army veteran and former bar owner and militia organizer from Woodstock, Ohio; and Thomas Caldwell, 68, a retired Navy intelligence officer from Berryville, Va.

Rhodes's defense has been hampered by the indictments in June and August of two of his key aides - deputy Michael Greene and attorney SoRelle, respectively - whose ability to testify may be limited without jeopardizing themselves.

Linder and Bright, Rhodes attorneys, have also quarreled with Rhodes, who sought to replace them three weeks before trial. Edward T. Tarpley Jr. for now has joined Rhodes's team, injecting another dose of uncertainty into the proceedings.