Cellphone video shows the end of the April 13 encounter when a man is seen physically grabbing and wrestling one of the alleged victims out the door of the bar and throwing him to the ground.
"You've been warned," he growls in the video, as the alleged victim lies on the ground in apparent pain.
Newport Beach police say two people were battered in the incident and they are looking for the suspect seen on video. They asked for the public's assistance.
The incident began around 8 p.m. that night when the three men decided to go to Siena Restaurant at the Balboa Inn for dinner, the Orange County Register reported.
They said the bartender was immediately hostile to them, asked to see identification and proclaimed one of them a fake. The men say the ID was real and in a lawsuit they allege the request was a ruse to not serve gay men.
Two videos posted online capture only part of the encounter. In one, the bartender can be heard pointing to someone and saying "Get them out of here. I don't want to hear it. You need to go."
A man in the bar, believed to be a patron and not an employee, then lifts one of the men off his stool and carries him out the door and throws him to the ground outside the restaurant.
Police say they are investigating an alleged battery against two men.
Management at the Balboa Inn has declined to comment.
Newport Beach asked anyone with information to call Detective Rick Henry at (949)644-3790 or leave an anonymous message on the department's recorded hotline at 1-800-550-NBPD.