Updated

Three Connecticut state troopers are accused in a lawsuit filed Thursday of violating the constitutional rights of a protester at a sobriety checkpoint by seizing his pistol and camera and then arresting him on bogus criminal charges.

The American Civil Liberties Union of Connecticut filed the lawsuit in federal court on behalf of protester Michael Picard. Named in the lawsuit, which does not say how much money in damages is being sought, are troopers John Barone, Patrick Torneo and John Jacobi.

Trooper Kelly Grant, a state police spokeswoman, said an internal affairs investigation is active and referred other questions to the state attorney general's office, which declined to comment. The three troopers didn't immediately return messages Thursday.

Picard has become known to state and local police in the Hartford area for protesting drunken driving checkpoints, which he says are constitutional search and seizure violations and a waste of public money, the lawsuit says.

At a checkpoint in West Hartford on Sept. 11, 2015, Barone confiscated Picard's legally carried pistol, pistol permit and camera on the pretext of public complaints, the lawsuit says. The troopers then got together and fabricated charges, not knowing they were still being recorded by Picard's camera after they seized it, according to the ACLU.

The troopers are heard but not seen on the recording calling a Hartford police officer to see if he or she had any "grudges" against Picard, initiating an investigation of him in a police database and discussing a previous protest Picard organized at the state Capitol, the lawsuit says.

After finding that Picard had a valid pistol permit, Barone tells the other troopers they have to "cover" themselves and either Torneo or Jacobi said "let's give him something," the lawsuit says. The troopers then wrote Picard infraction tickets for illegal use of a highway by a pedestrian and creating a public disturbance — charges later dismissed in court.

"Police should be focused on public safety, not punishing protesters and those who film public employees working on a public street," said Dan Barrett, legal director of the ACLU of Connecticut. "As the video shows, these police officers were more concerned with thwarting Mr. Picard's free speech and covering their tracks than upholding the law."