Updated on February 11, 2016 8:22pm

GUILTY: NYPD Officer Peter Liang Convicted in Trial for Killing Akai Gurley

DOWNTOWN BROOKLYN — Rookie NYPD officer Peter Liang is guilty of manslaughter for fatally shooting an unarmed man in a Brooklyn housing project in 2014, a jury ruled Thursday night.

The decision caps a two-week trial for shooting Akai Gurley, 28, during a patrol of a dimly lit stairwell at the Pink Houses, located at 2724 Linden Blvd., on Nov. 20, 2014.

"This is a tragedy," Brooklyn District Attorney Ken Thompson told NY1. "There are no winners here, but justice was done."

The mostly white jury of seven men and five women deliberated for three days before reaching its decision.

"We're not rejoicing, but it's about being accountable," said Hertencia Petersen, Gurley's aunt. "It's about innocent life. I was overwhelmed. I'm not rejoicing but justice has been served."

Liang, 28, faces up to 15 years in prison when he's sentenced in April. He was immediately fired from the NYPD, and remains out on bail.

"Obviously he’s distraught," Liang's attorney Robert Brown told NY1. "It’s a tragic accident. It’s not going to bring back Mr. Gurley."

Liang went with a private attorney to defend him instead of lawyers from the Patrolmen's Benevolent Association. Still, the police union president issued a statement.

“We are very disappointed in the verdict and believe that the jury came to an absolutely wrong decision.  This was a terrible and tragic accident and not a crime," said PBA President Patrick Lynch. "This bad verdict will have a chilling effect on police officers across the city because it criminalizes a tragic accident.”

Liang, a rookie officer, and his partner Shaun Landau were doing a top-to-bottom patrol of an apartment building on Nov. 20, 2014 when Liang fired his gun. The bullet ricocheted off a concrete wall and fatally struck Gurley in the chest.

Prosecutors initially said they didn't believe Liang intended to kill Gurley, but later argued that he deliberately shot into the dark after hearing a loud noise.

“He heard a sound in a darkened stairwell,” said Assistant District Attorney Joseph Alexis. “He had a working flashlight in his hand, and he never used the flashlight to see what the sound was below him... An innocent man is dead because he heard a sound."

Liang didn't provide medical assistance and didn't report the shooting over his police radio for four minutes, prosecutors said.

Instead, he bickered with Landau about who should radio in the shooting and worried that he'd be fired from the force.

“[Liang] thought he was going to be fired. I said, 'No, you're not, it's just an accidental discharge,'” Landau, who was a prosecution witness, testified. “I told him to call, and he told me to call. He says, 'You call.' I said, 'You call.'”

Meanwhile, Gurley's girlfriend Melissa Butler, who he'd been visiting in the building, was shrieking over his body and can be overheard in a 911 call that was played for the court during the trial.

During jury selection, Justice Danny K. Chun hoped to keep anyone with connections to the Pink Houses off the jury and dismissed some people who were familiar with them or lived nearby.

The judge also dismissed roughly 20 potential jurors who said they couldn't be impartial toward police because they were friends with officers or were biased by recent media attention on instances of police brutality.

The jury was a cross-section of New Yorkers, including an after-school volunteer, an Irish immigrant and a fan of "Downton Abbey."

One juror hired people to re-enact crimes for a documentary series on NBC. Another works as a sous chef at the Brooklyn Museum. And yet another was a Cooper Union graduate who works for a Brooklyn tool retailer but had also been mugged at gunpoint recently.

Mayor Bill de Blasio said in a statement he respects the jury's decision. 

"We hope today's outcome brings some closure to the Gurley family after this painful event," de Blasio said.  

With reporting by Rachelle Blidner, Ben Fractenberg, Trevor Kapp and John Santore