University of Virginia student Martese Johnson has filed a $3m lawsuit against the state liquor agents involved in his bloody and highly scrutinized arrest.

Johnson, 21, filed the complaint on Tuesday in US district court in Charlottesville, alleging unlawful detention and excessive use of force by three officers from the Alcohol Beverage Control state agency.

Video and photos of Johnson being pinned to the sidewalk by ABC agents after they detained him outside a bar during the March arrest went viral on social media and prompted huge protests on campus attended by students and university leaders.

Johnson, who is black, could be heard on the video calling the white officers racist.

He was taken away in a police van with his hands cuffed behind his back and his legs shackled, and later treated in hospital for gashes to his head that needed stitches and have left permanent scars.

“The positive takeaway from this lawsuit is that this issue is being discussed and the interaction between police and citizens being questioned,” said Daniel Watkins, a Charlottesville lawyer who represented Johnson in his criminal case and filed the lawsuit on his behalf on Tuesday.

“It was a terrible ordeal for Martese to go through,” he told the Guardian.

It emerged in August that Johnson was planning to sue for damages, as the Guardian revealed, and that he was unhappy that the agents involved had not been suspended or, apparently, punished in any way, and also that the state’s report into the incident had been kept under wraps.

The report has since been released and Virginia’s governor, Terry McAuliffe, signed an executive order mandating improvements in standards at the Virginia ABC agency, which has come in for criticism about aggressive arrest tactics before.

Johnson’s lawsuit on Tuesday stated that the agents’ “brutal and unjustified” attack on the UVA student has left him with disfiguring facial scarring.

Two ABC officers restrained him outside a bar opposite the bucolic UVA campus after he had been turned away on suspicion of producing a fake ID to enter the bar, though the ID later turned out to have been valid.

The two officers “all of a sudden and without provocation … slammed Martese into the brick walkway, face first, causing Martese to suffer a severe laceration to his forehead and scalp,” the lawsuit states.

A third officer then assisted in the arrest. Johnson was charged with obstruction of justice and public intoxication or swearing, but those charges were later dropped. After an investigation, however, the Charlottesville prosecutor determined that the agents did nothing wrong and declined to file charges.

“The reasonable conclusion from that outcome is that the officers were not disciplined,” said Watkins.

Johnson is now in his final year at UVA. He has talked passionately about growing up in a single-parent household in Chicago and witnessing both aggressive and considerate behavior from the police toward African Americans on the South Side, where he lived.

Earlier this month, he wrote an opinion article for Vanity Fair in which he said that his violent arrest and subsequent detention gave him a glimpse into the world of slavery. In that article, he also cited the Guardian’s ongoing work in recording violent civilian deaths at the hands of the police in its series The Counted.

“I know that Martese sees himself as an agent of change. But he has filed this lawsuit in his own name and you saw what happened to him that night. The question at the centre of this is: was this an appropriate level of force used?” Watkins said.

The March incident prompted McAuliffe to order additional training for ABC’s 130 officers and appoint a taskforce to examine the agency’s law enforcement practices. The taskforce last month declined to recommend stripping ABC of its arrest powers but recommended that the agency emphasize regulatory activities, such as licensing compliance, over law enforcement.

McAuliffe also ordered a state police investigation, which concluded that agents “only used physical force to detain and arrest Johnson” and did not employ any of the more aggressive tactics that agents are allowed to use when a person resists arrest. The agents were trying to question Johnson, who was then 20, after he showed identification but was turned away from a bar across the street from the university campus in the early hours following St Patrick’s Day celebrations.

Johnson’s lawsuit names the ABC, agency director Shawn P Walker, and agents Jared Miller, Thomas Custer and John Cielakie as defendants.

An ABC spokeswoman, Kathleen Shaw, said the agency does not comment on pending litigation. The attorney general’s office did not immediately respond to an email seeking comment.

Johnson’s arrest was the second ABC incident to provoke outrage in Charlottesville. Two years ago, several agents who mistook a carton of sparkling water for beer swarmed a vehicle driven by UVA student Elizabeth Daly. One agent brandished a gun and another tried to break her windshield with a flashlight. The agent who used the flashlight was John Cielakie, the same agent named in Johnson’s lawsuit.

Daly fled in a panic, grazing two agents with her vehicle after asserting that they were not in uniform or carrying badges and she did not know they were law enforcement agents.

Charges against her were dropped, and she settled a lawsuit against the ABC for $212,500.