In December, Thomas Brocuglio’s dash cam was rolling as he approached the intersection of France Street and Cromwell Avenue in Rocky Hill.

He was trying to make a right on red.

“What are you doing?" Brocuglio said inside his car to the driver in front of him.

The driver in the truck in front of Brocuglio was identified in an arrest warrant as off-duty Meriden police officer Corporal Allen Ganter. He's seen on dash-cam video getting out of his Toyota Tacoma and waving his badge.

“You can’t turn on red,” Ganter said.

“Really? Where does it say that? It says 'stop here on red,' and you are the one sitting on your phone,” Brocuglio said.

The interaction between the two men then intensified - Ganter is seen on dash-cam video reaching into Brocuglio’s car and punching him.

“You are going to get arrested for assaulting a civilian,” Brocuglio said.

Brocuglio told officers he was left dazed, and possibly concussed, with swelling and redness and irritation to his left cheek, according to an arrest warrant.

Police approached Ganter at a residence where they tried taking his statement.

“So, he is saying that I hit him?” Ganter said. “And there is nothing I can press for breach of peace, for him yelling at me?”

Police body-worn camera captured Ganter admitting he hit Brocuglio.

“My fault, I’m wrong, I shouldn’t have," Ganter said.

Following an internal affairs investigation, Meriden police said Ganter did violate the department's rules of conduct.