Jon Schaffer
© WELT
Oath Keepers' Jon Schaffer
A member of the far-right Oath Keepers militia pleaded guilty Friday to two charges stemming from his involvement in the Jan. 6 Capitol siege.

Why it matters: It's the first guilty plea that federal prosecutors have secured in their sprawling investigation, and it comes exactly 100 days after the Jan. 6 siege. Jon Schaffer, 53, is expected to cooperate with the government and will receive "witness security."
  • Schaffer turned himself in to the FBI on Jan. 18 and has been jailed since. He originally faced six charges, including for using bear spray on police officers, but he will now plead guilty to obstruction of an official proceeding and entering a restricted building with a dangerous weapon.
  • The Oath Keepers are a far-right group made up of former military, law enforcement and first responders.
The big picture: Prosecutors last month requested a delay in a series of cases related to the Jan. 6 Capitol riot, describing the massive undertaking as "likely the most complex investigation ever prosecuted by the Department of Justice."
  • More than 300 suspects have been charged in connection with the attack, which FBI director Christopher Wray has described as "domestic terrorism."
  • In addition to individual crimes like assault, trespassing and destruction of government property, federal prosecutors are investigating "conspiratorial activity" that began before Jan. 6, including possible coordination between the Oath Keepers and other far-right groups.
  • The Justice Department expects that at least 100 more individuals will be charged, according to the court filing.