The attorney for a Montana man accused of slamming a 13-year-old boy to the ground for not removing his hat during the national anthem before a rodeo said Wednesday his client believes he was acting on an order from President Donald Trump. The president's "rhetoric" contributed to Curt Brockway's disposition when he allegedly grabbed the boy by the throat and slammed him to the ground at the Mineral County fairgrounds Saturday,

Jasper said Brockway is a U.S. Army veteran who believes he was acting on an order by the commander in chief. He added that Brockway's decision-making has been affected by a traumatic brain injury he suffered in a vehicle crash in 2000 while he was stationed at Fort Lewis, Washington.

"His commander in chief is telling people that if they kneel, they should be fired, or if they burn a flag, they should be punished," Jasper said. "He certainly didn't understand it was a crime."

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Brockway, 39, told a sheriff's deputy that he asked the boy to remove his hat out of respect for the national anthem before the start of the county rodeo, Mineral County Attorney Ellen Donohue wrote in the document describing the attack. The boy cursed at Brockway in response, and the man grabbed him by the throat, "lifted him into the air and slammed the boy into the ground," Donohue wrote. The teen was airlifted to a hospital with a possible concussion and skull fracture, Mineral County prosecutor Elena Donahue wrote in court documents, according to the Associated Press.

Conduct during the playing of the national anthem has been an issue in recent years, with some NFL players kneeling to protest police brutality. Trump once called for NFL owners to fire players who kneel or engage in other acts of protest during the anthem.

"Trump never necessarily says go hurt somebody, but the message is absolutely clear," Jasper said. "I am certain of the fact that (Brockway) was doing what he believed he was told to do, essentially, by the president. ... Everyone should learn to dial it down a little bit, from the president to Mineral County."

Brockway, who is charged with felony assault on a minor, is a registered violent offender after being convicted of a 2010 charge of assault with a weapon.