MARKSVILLE, La. (CBS NEWS)-- A Louisiana law enforcement officer was convicted Friday on a lesser charge of manslaughter in a shooting that killed a 6-year-old autistic boy, a gruesome encounter captured on tape by another officer’s body camera. 

Jurors found Derrick Stafford guilty of manslaughter and attempted manslaughter charges, multiple news outlets reported. He had faced charges of second-degree murder and attempted second-degree murder in the case. 

A manslaughter conviction in Louisiana carries a sentence of 15 to 40 years in prison, CBS affiliate WAFB reports. 

Stafford, 33, and another deputy city marshal opened fire on a car - killing Jeremy Mardis and critically wounding his father - after a 2-mile car chase in Marksville on the night of Nov. 3, 2015. 

Video from a police officer’s body camera shows the father, Christopher Few, had his hands raised inside his vehicle while the two deputies collectively fired 18 shots. At least four of those bullets tore into Jeremy, who died within minutes. 

Louisiana Attorney General Jeff Landry said in a statement that his office is happy with the verdict, 

“As we have said all along, our goal in this case was to get justice for Jeremy Mardis, his family, and the people of Louisiana. Today, that happened,” the statement said.

Stafford testified Friday that he shot at the car because he feared Few was going to back up and hit the other deputy, Norris Greenhouse Jr. 

“I felt I had no choice but to save Norris. That is the only reason I fired my weapon,” Stafford said. 

Greenhouse, 25, faces a separate trial on murder charges later this year. 

Stafford cried when a prosecutor showed him photographs of the slain first-grader. He said he didn’t know the boy was in the car when he fired and didn’t see his father’s hands in the air. 

“Never in a million years would I have fired my weapon if I knew a child was in that car. I would have called off the pursuit myself,” Stafford said. 

Two other officers at the scene - a third deputy city marshal and a Marksville police officer - didn’t fire their weapons that night. Prosecutors said the officers weren’t in any danger and shot at the car from a safe distance, with none of their bullets hitting the front or back of Few’s vehicle. 

Jurors heard testimony that Stafford fired 14 shots from his semi-automatic pistol. Stafford said Greenhouse stumbled and fell to the ground as he tried to back away from Few’s car. 

Stafford and Greenhouse are black. Few is white, and so was his son. 

Defense attorneys accused investigators of rushing to judgment, arresting the officers less than a week after the shooting. One of Stafford’s attorneys has questioned whether investigators would have acted more deliberately if the officers had been white. 

Stafford’s attorneys tried to pin the blame for the deadly confrontation on Few. They accused the 26-year-old father of leading the four officers on a dangerous, high-speed chase and ramming into Greenhouse’s vehicle before the gunfire erupted. 

During the trial’s opening statements, defense attorney Jonathan Goins called Few “the author of that child’s fate.” Goins also said Few had drugs and alcohol in his system at the time of the shooting. 

But prosecutors said none of the father’s actions that night can justify the deadly response. Marksville Police Lt. Kenneth Parnell, whose body camera captured the shooting, testified that he didn’t fire at the car because he didn’t fear for his life. 

Few testified on Tuesday that he never heard any warnings before two officers fired. He said he learned of his son’s death when he regained consciousness at a hospital six days after the shooting, on the day of Jeremy’s funeral. 

A prosecutor, Matthew Derbes, asked Few if he regrets not stopping his car when he saw the blue lights from an officer’s vehicle. 

“Most definitely,” Few said. “Every day.” 

But he insisted he was driving safely and wasn’t trying to escape. Few said he kept driving in hopes of catching up with a girlfriend in a van ahead of him, so that she could take care of his son if he got arrested. 

“The whole reason there was even a chase was for his well-being,” he said. 

Stafford’s defense team also focused on the his upbringing, including his family’s military background, his relationship with his wife and three kids, and his 400-plus hours of police training, WAFB reports. 

Stafford became emotional on the stand, saying he was trained to stop a threat and not to kill.  

Stafford, a Marksville police lieutenant, and Greenhouse, a former Marksville police officer, were moonlighting on the night of the shooting. 

Before the shooting, Stafford and Greenhouse both had been sued over claims they had used excessive force or neglected their duties as police officers. The Marksville Police Department suspended Stafford after his indictment on rape charges in 2011, but reinstated him after prosecutors dismissed the charges.