Joshua Lollar, 39, a decorated military veteran, according to Army officials, faces federal charges after he was seen on Facebook live video clashing with police officers, according to court documents.
He went before a magistrate judge and was issued a $50,000 bond.
Lollar told FBI agents he traveled to Washington and attended the speech given by President Donald Trump at the Ellipse before returning to his car, the agent said.
Lollar later got out and followed a crowd headed toward the Capitol. Body camera footage from D.C. Metro police officers showed a man believed to be Lollar wearing a gas mask, gloves and a tan-colored body armor vest, court documents stated.
His father defended his son when reached by phone recently.
"He's not a domestic terrorist or insurrectionist," Grover Lollar told ABC13. "He went for a rally. They just rushed down there, and he got swept along."
Grover also said his son has a disability.
"He's a good man," Grover Lollar said. "He's not a criminal."
In a pre-trial hearing last week, the court discussed Lollar's history of psychological issues and if he had to remain in custody until trial.
Prosecutors said Lollar's admittance of having guns was an issue that could complicate his release, and until someone else came to court to say his guns were in their possession, they would prefer Lollar remain detained.
According to the FBI, Lollar is charged with knowingly entering or remaining in any restricted building or grounds without lawful authority and impeding or disrupting official functions. If convicted, he could face a year in prison and a $100,000 fine.
He's also charged with obstructing or impeding a law enforcement officer during civil disorder and obstructing federally protected functions. If convicted, Lollar could face up to five years in jail with a $250,000 fine.
Lastly, he's charged with violent entry and disorderly conduct on Capitol grounds, for which he could be jailed up to six months and pay a $5,000 fine.
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Five people died during the ordeal, including a U.S. Capitol police officer.
This video above is from previous reporting.