The Tennesseen man shot by police on Monday after allegedly waving a pellet gun at the US Capitol referred to himself as a "prophet of God".
The gunman, Larry Russell Dawson, 66, of Antioch, Tennessee, had been arrested in October 2015 for shouting from the balcony of the House of Representatives that he was a "prophet of God".
Dawson, who is banned from Capitol grounds, was at the visitor centre's security gate on Monday when his gun set off a metal detector, according to a federal source.
"He drew what appeared to be a weapon," said US Capitol Police Chief Matthew Verderosa. "He pointed it at a police officer."
An officer then opened fire and shot Dawson, who was transported to hospital for surgery.
Dawson was later charged with assault with a deadly weapon and assault on an officer.
Legal issues involving Dawson date back at least 20 years.
When he declared himself "a prophet of God" inside the House, he was arrested for disrupting proceedings, assaulting a police officer and unlawful conduct on Capitol grounds, according to court documents.
He was later released, but when he did not appear in court, a bench warrant was issued for his arrest.
After Washington DC officials notified him of the warrant, Dawson wrote a letter to them, according to NBC.
"I have been called chosen and sent unto You this day," he wrote.
"Therefore, I will not comply with the court order, nor will I surrender myself unto your office. No longer will I let myself be governed by flesh and blood, but only by the Divine Love of God!!!!"
Dawson had previously been fired from his job as a school bus driver, after harassing a teenage girl and writing her letters declaring his love.
In one of these letters, he claimed God had told him to ask the girl to live with him.
He was found "not guilty – reason of insanity" on two of three harassment charges, and acquitted of the third.
Dawson subsequently lost his job as an undertaker, on grounds of moral character.
Challenging the funeral boards' decision to revoke his licence, Dawson defended his actions: "Any time that a minister is being led by God, and he gives you a direct command to do something, it's left up to you to do it or not to do it," he said.
