Iced Earth guitarist Jon Schaffer has entered "advanced plea negotiations" with federal prosecutors following his arrest for his apparent involvement in January's storming of the U.S. Capitol Building.

Even more, the plea talks are the first and farthest along of any Capitol Riot defendant. On Jan. 6, supporters of former President Trump attacked the historic Washington, D.C., meeting place of the U.S. Congress. Rioters forcibly breached security in failed attempt to prevent the Electoral College certification of Joe Biden's 2020 election victory. More than 300 of the insurrectionists have since been charged with crimes.

But only Schaffer has gotten to this stage in a plea bargain agreement. Still, the fact that the public even knows Schaffer's cooperating with the government is only due to a recent court filing being accidentally made public, BuzzFeed News reported.

Indeed, the public brief had seemingly "been made in error," but BuzzFeed got a look at it. In it, Assistant U.S. Attorney Ahmed Baset said prosecutors worried that disclosing Schaffer's cooperation would "reveal the existence, scope and direction of the ongoing and confidential investigation." The filing was quickly removed from the public docket.

The Iced Earth guitarist was arrested on Jan. 17 in his home state of Indiana after appearing on the FBI's "Most Wanted" list. His likeness at the Capitol was captured both in photographs used by authorities and purportedly in an amateur video. Schaffer faces six federal charges.

But it's yet to be seen how those charges will shake out now that the musician has started talking with authorities. Schaffer has been doing "debrief" interviews with the government — they're an indication that more in-depth discussions about a plea for the Iced Earth member may soon follow.

"We have our first plea agreement negotiation in the US Capitol Insurrection," investigative reporter Scott MacFarlane shared on Twitter on Monday (April 5) alongside an image of the new court filing. "Oath Keeper Jon Schaffer [is] accused of attacking police. … Feds says Schaffer is an 'anarchist' who views government as 'criminal enterprise.'"

Oath Keepers is a far-right militia organization comprised mainly of former military and law enforcement that, following the violent Jan. 6 mob, distanced themselves from the musician, as MetalSucks noted. Schaffer's wearing an "Oath Keepers Lifetime Member" hat in the images of him taken at the Capitol. In January, CNN revealed an Oath Keepers organizer had been charged with coordinating the riot.

As previously reported, Tuesday (April 6) is Schaffer's next court date. The hearing was prompted by the musician's motion for pre-trial release after a judge earlier ruled the rocker be held without bond.

Iced Earth, the heavy metal act Schaffer founded in 1985, won't be the same following his legal battles. While Schaffer's bandmates issued conflicting statements immediately after the riot, vocalist Stu Block and bassist Luke Appleton ultimately decided to leave the group in February.

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