According to the criminal complaint, Worthington Police Officer Colby Palmersheim was driving his squad car when Promvongsa pulled up behind him "at a high rate of speed. Promvongsa was so close that Palmersheim could not see the hood of Promvongsa's vehicle."

The officer claims Promvongsa was attempting to pass him, so he moved over slightly, at which point Promvongsa swerved toward his car, says the report.

Palmersheim reported that Promvongsa continued to tailgate him, driving behind him at a fast rate, while sticking his hand out the window and making some type of motion. He claimed that Promvongsa then pulled up to Palmersheim, rolled down his window, and told the officer to "stay there as he was going to go get his boys and come back."

A nearby police officer was aware, from prior contact with Promvongsa, that he didn't have a driver's license.

Agent Joe Joswiak of the Buffalo Ridge Drug Task Force, a multi-jurisdictional task force that includes Worthington Police, eventually gave chase. He claims he turned on his squad's emergency lights, but Promvongsa did not stop. Joswiak eventually made the arrest.

None of these allegations leading to Promvongsa's arrest were captured in independent traffic camera or dash cam footage, says his attorney Ginny Barron. She says the complaint relies on the officers' word alone.

"[Promvongsa's] obviously plead not guilty and we intend to try it. He maintains his innocence," Barron says. "What I can say is while I believe there are definitely a number of honorable police officers in the community who are highly respected, we are seeing increasing, systemic problems of excessive force in the Worthington Police Department, Nobles County Sheriff's Office, and Buffalo Ridge Drug Task Force that we don't believe should ever be allowed or tolerated in a civilized society."

However, dash cam footage released Thursday by the American Civil Liberties Union did capture the arrest.

It shows Promvongsa pulling over and Joswiak approaching his vehicle with gun drawn, shouting, "Get the fuck out of the car, motherfucker. Show me your hands."

Joswiak opens the door and tries to pull Promvongsa from the car while he's apparently still buckled into his seat. When Promvongsa doesn't immediately emerge, Joswiak begins to knee and punch him.

Soon, the dash cam audio is inexplicably shut off.

"Promvongsa was not given proper time to obey the officer’s orders before excessive force was used against him," said Teresa Nelson, executive director of the ACLU, in a statement.

“Agent Joswiak’s use of force against Anthony Promvongsa is disturbing and completely unnecessary. We are calling for an investigation of Agent Joswiak’s behavior and for him to be held accountable for his brutal attack on Anthony Promvongsa, up to and including termination and prosecution."

Joswiak has received no discipline, according to the ACLU. Promvongsa is charged with two counts of assault with a deadly weapon (his car), one count of fleeing a peace officer in a motor vehicle, possessing a small amount of marijuana, and driving with a revoked driver's license. He has pleaded not guilty.

"I had no idea what was going on when I was approached and attacked by this officer,” Promvongsa said in a statement. “I did not even have the opportunity to take off my seatbelt before I was literally blindsided with this unnecessary attack. I immediately pulled over for the Worthington squad car and before I knew what was happening I was beat and ripped from my vehicle."

The Worthington Police Department was surprised by this video Thursday and did not immediately respond for comment after it was shared with the department.