SAN JOSE — A man has filed an excessive-force lawsuit that alleges San Jose police needlessly blinded him in one eye with a rubber bullet during a suicidal episode inside an East San Jose mini-mart last December.

The federal complaint filed in late October seeks unspecified damages from the City of San Jose, former Chief Larry Esquivel and 30 unidentified defendants, most of whom are presumed to be San Jose police officers present at the Dec. 15, 2015 encounter at the Shop-N-Go at South Jackson and Alum Rock avenues.

Benjamin Cooper, the plaintiff, contends that he was in the store and threatening to hurt himself with a knife, and was seen pressing the weapon against his throat, according to the suit. The store clerk called 911, and arriving officers cleared out other occupants of the store.

Cooper followed them outside and reportedly paced back and forth with the knife against his neck. Both police and the plaintiff agree that the officers repeatedly ordered Cooper to drop the knife, and at some point the officers fired “less than lethal” rounds at Cooper.

The suit states that Cooper was hit in his left leg, chest, and right eye, and that he permanently lost vision in that eye, “which causes him pain and has exacerbated his condition related to anxiety and panic attacks.”

The suit’s main point of contention is that Cooper did not pose a threat to anyone’s safety but his own, and that police did not attempt to de-escalate the situation, as they are generally trained to do when dealing with a person who is mentally ill or experiencing a mental-health crisis.

“Mr. Cooper was not a danger to the officers or anyone else at the scene. I don’t see how they’re going to deny that fact,” said Che Hashim, one of the attorneys representing Cooper. “Hopefully this will shine a light on the need to train the police and re-evaluate the use of these non-lethal devices. They totally blinded this guy, his eye is un-openable, and that can’t possibly be helpful to his mental state moving forward.”

San Jose police deferred questions about the suit to the City Attorney’s Office, which declined comment as it usually does when asked about pending litigation.

Neither the suit nor police accounts of the encounter specifically mention whether any of the responding officers were trained in crisis intervention, which the department declared earlier this year would be an eventual requirement for all of its officers.

Dennis Kenney, a professor at New York’s John Jay College of Criminal Justice and an expert in police training, said the encounter highlights a routine dilemma for officers when dealing with people who are threatening no one else but themselves.

“The ideal way to handle that situation would be to talk the guy down, into surrendering, but that’s not always feasible,” Kenney said. “You can’t disarm him by force, since the guy’s got a knife, it puts (the officers) at risk. The problem with a Taser is that it’s not 100 percent, and if you miss, then the individual cuts his throat.”

“The moral and legal obligation on police is to do something. They can’t just walk away,” Kenney said. “But the choices available to them aren’t good. My guess is they wish they aimed better.”

Kenney also noted that over the years, police have increasingly become first responders to mental-health crises, which he said isn’t always the best match for the problem.

“I empathize, but this is less the responsibility of the police, and more on family and the social-service network around them,” he said. “Blaming that failure on police probably doesn’t get you very far.”

Check back later for updates to this story.