(CNN)As the Justice Department's January 6 investigation takes a new turn with the use -- for the first time in the Capitol attack prosecutions -- of the seditious conspiracy charge, the founder of the Oath Keepers and another individual facing the charge will make their first appearance in court Friday.
The Justice Department on Thursday unveiled its case against Stewart Rhodes and Edward Vallejo, who were both arrested Thursday in Texas and Arizona, respectively.
The court filings made public Thursday also added the charge to the case that nine other defendants were already facing for their alleged involvement in the riot that disrupted Congress' certification of President Joe Biden's election win on January 6.
At some point, those defendants will have an arraignment for them to enter their plea to the new seditious conspiracy charge, but those proceedings have not been scheduled yet,
Rhodes -- the leader of the far-right Oath Keepers -- will appear before Magistrate Judge Kimberly Priest Johnson in Plano, Texas, 2:30 pm CT on Friday.
Vallejo -- who prosecutors accuse of transporting weapons and coordinating with Rhodes a so-called "quick reaction force" team for January 6 -- will appear virtually in a Phoenix hearing at 12:30 pm MT, before Magistrate Judge Deborah Fine.
The hearings are what is known as a first appearance hearing, and it is not expected that the two defendants will enter their pleas. Instead, the hearings will concern their pretrial release and potential bail conditions.
It's possible at the hearing the Justice Department argues forcefully for the men to be held in jail, as they had done with several others in the case already, and prosecutors could even show evidence to the court to convince the judges they could be dangerous
Those discussions may continue when their cases -- as is expected -- move to DC's federal court, where the other January 6 prosecutions are proceeding.
Rhodes has previously denied wrongdoing.
Prosecutors' decision to bring the charge seditious conspiracy carries symbolic and political weight; the relevant statute dates back to the Civil War-era. But it is also a risk for prosecutors, as use of the charge in the past -- most recently in a 2010 case concerning a militia plot in Michigan -- has faltered under scrutiny from judges.
Attorney General Merrick Garland had been reluctant to bring the charge, CNN previously reported, but prosecutors in the latest indictment were able to show granular details of alleged planning and logistics coordination among the defendants in the lead up to the Capitol attack. Of particular note are the accusations in the new filings that Rhodes, Vallejo and other defendants continued plotting even after the riot to disrupt the peaceful transfer of power.
Before the seditious conspiracy charge was brought, a central charge in DOJ's Oath Keeper case was conspiracy to obstruct an official proceeding. US District Judge Amit Mehta recently rejected the request by several Oath Keeper defendants that he throw that charge out, and its use has been upheld by other judges presiding over separate January 6 cases.
Several Oath Keepers who do not currently face the seditious conspiracy charge brought by the DOJ Thursday face a conspiracy obstruction charge. That charge, as well as the seditious conspiracy charge, carries a 20-year maximum prison sentence.
Four of those indicted in the DOJ's Oath Keepers' prosecutions are known to be cooperating with the government.
CNN's Katelyn Polantz, Even Perez, Hannah Rabinowitz and Marshall Cohen contributed to this report.