A New York City police officer was convicted on Friday of second-degree manslaughter after he tossed a picnic cooler filled with drinks at a fleeing suspect, causing the man to fatally crash his motorized scooter in 2023.

Judge Guy Mitchell handed down the guilty verdict in Bronx criminal court in the case against Sgt Erik Duran in the death of Eric Duprey. The 38-year-old Duran was the first New York police department (NYPD) officer in years to be tried for killing someone while on duty.

“The fact that the defendant is a police officer has no bearing,” the judge said before reading out his verdict in a brief hearing. “He’s a person and will be treated as any other defendant.”

Members of Duprey’s family sobbed as the decision was read out. Orlyanis Velez, Duprey’s wife, said after that she was happy but also surprised.

“I was waiting for justice just like everybody, but when the moment happens, you can’t believe it’s happening,” she said outside the courthouse. “It’s been a lot of time. These people been killing citizens, been killing everybody. They don’t give no reason.”

Erik Duran arrives at Bronx criminal court on Friday. Photograph: Kena Betancur/AP

Duran did not appear to react when the decision was handed down, and his lawyer and spokespersons for his police union did not immediately respond to emails seeking comment.

Duran had been suspended with pay pending the trial, but the department confirmed on Friday he had been dismissed following his conviction, as state law mandates. Duran now faces up to 15 years in prison when he is sentenced on 19 March.

The state attorney general, Letitia James, whose office prosecuted the case, offered her condolences to Duprey’s family.

“Though it cannot return Eric to his loved ones, today’s decision gives justice to his memory,” she said in a statement.

Duran also faced charges of criminally negligent homicide and assault.

Mitchell dismissed the assault count earlier, saying prosecutors failed to show he intended to hurt Duprey. He also did not deliver a verdict on the criminally negligent homicide charge as he had already found Duran guilty of the more serious manslaughter charge.

Duran had pleaded not guilty and opted for a bench trial – meaning the judge, not a jury, would render the verdict.

Authorities say that on 23 August 2023, Duprey sold drugs to an undercover officer in the Bronx and then fled.

Duran, who had been part of a narcotics unit conducting the operation, is seen in security footage grabbing a nearby red cooler and quickly hurling it at Duprey in an attempt to stop him.

The container full of ice, water and sodas struck Duprey, who lost control of the scooter, slammed into a tree and crashed on to the pavement before landing under a parked car.

Prosecutors said the 30-year-old, who was not wearing a helmet, sustained fatal head injuries and died almost instantaneously.

Duran, testifying in his own defense, said he only had seconds to react and was trying to protect other officers from Duprey as he sped toward them. He told the court he immediately tried to render aid after seeing the extent of Duprey’s injuries.

“He was gonna crash into us,” Duran said in court. “I didn’t have time. All I had time for was to try again to stop or to try to get him to change directions. That’s all I had the time to think of.”

But prosecutors maintained Duprey did not pose a threat – and that his death was not accidental but the result of Duran’s reckless, negligent and intentional actions.

They suggested the officer had enough time to warn others to move but instead tossed the cooler in anger and frustration.