Prosecutors have declined to file charges against a white Little Rock police officer who killed a black man by firing at least 15 shots into the windshield of the car the man was driving.

The Pulaski county prosecutor, Larry Jegley, said on Friday Charles Starks would not face charges in the 22 February shooting of Bradley Blackshire. Police said Starks was responding to a call after a detective confirmed the car was stolen.

A 25-minute video of the incident released last month showed Starks on the vehicle’s hood shooting at Blackshire, 30, through the windshield as the car moved.

“Starks was confronted with the imminent threat of deadly force in two forms: 1) the vehicle that was driving toward him and from which he had no duty to retreat, and 2) his reasonable belief that Mr Blackshire was going to shoot him,” Jegley wrote in a letter to the city’s police chief.

“Starks’ use of force, under Arkansas law and prior decisions by the United States supreme court, was justified.”

Little Rock police said they had completed an internal investigation and said a final decision would take approximately two weeks. Police said Starks was still being paid but not performing any departmental duties. Starks was ordered to surrender his badge and gun after the shooting.

Omavi Shukur, a lawyer for Blackshire’s family, released a statement on Friday night.

“Charles Starks’ actions were criminal,” the statement said. “The family disagrees with the prosecutor’s decision and will be undeterred in our pursuit of justice.”

The video showed that almost immediately after Blackshire’s car backed into a space in a parking lot, a police SUV arrived with lights on and stopped nearby.

Starks then walked to the driver’s side window with his gun drawn and instructed Blackshire to get out of the car multiple times. Blackshire refused and asked: “What did I do?” and “What are you going to shoot me for?”

Blackshire then began to slowly drive away. Starks was knocked by the car and fired into the windshield four times. Blackshire momentarily stopped and Starks maneuvered in front of the vehicle, leaning on the hood.

When Blackshire continued to drive, Starks, now on top of the hood, shot at least 11 more times into the windshield. He stopped shooting and got off the car after a second officer, Michael Simpson, arrived and crashed into Blackshire’s vehicle.

Blackshire died at the scene.

Ammunition cartridges were found in Blackshire’s pockets and a loaded .45-caliber handgun was found in the car, Jegley wrote. A female passenger in the vehicle said she believed Blackshire was going to shoot Starks, he wrote.

The prosecutor wrote that Starks ordered Blackshire to get out of the vehicle at least 12 times and could not tell if Blackshire was reaching for something when he moved his hand down to put the car in gear.

An attorney for Starks said the officer was pleased with the decision.

“It relieves burden on him and his family. He wishes Mr Blackshire would’ve gotten out of the car and this would have never happened,” Robert Newcomb said in a statement to Little Rock television station KARK.

The shooting has prompted some protests in Little Rock, where the police department already faced questions about the use of no-knock warrants. A small group of protesters briefly shut down a downtown intersection in front of city hall on Tuesday night. The police chief, Keith Humphrey, met with the group and later said he supported their right to peacefully protest.

Mayor Frank Scott, who in December became the first African American popularly elected to lead the city, has called for an independent citizen review board to address use of excessive force by police. Scott has also called for equipping police officers with body cameras.

In a statement, Scott said he had spoken to Blackshire’s mother and “prayed with her”. He also said he was awaiting the results of a Department of Justice civil rights review of the case.