NEW YORK (CBSNewYork/AP) — Jurors began their deliberations Tuesday afternoon in the manslaughter and official misconduct trial of NYPD Officer Peter Liang, who shot an unarmed man in a dark public housing stairwell in Brooklyn.

Before deliberations began, the judge in the case dismissed one of the official misconduct charges against Liang.

In closing arguments, prosecutors said Liang “recklessly pulled the trigger” when he shot and killed Akai Gurley, 28, in November 2014 at the Pink Houses in East New York.

“It’s not true that this was a one in a million shot,” Assistant District Attorney Joe Alexis said. “Peter Liang fired a shot right at where Akai Gurley stood because he heard a sound on the seventh floor. An innocent man is dead because he heard a sound, a sound he can’t even describe.”

Investigators said Liang was holding his flashlight and his gun when he fired a single round in the pitch black stairwell. The bullet ricocheted and hit Gurley a flight below.

Prosecutors said he acted recklessly and then did little to help a dying man.

But in his closing arguments Tuesday morning, defense attorney Robert Brown spent two hours arguing that Liang’s shooting of Gurley was an accident and that he did everything he reasonably could to try to save Gurley’s life, CBS2’s Diane Macedo reported.

Brown said Gurley’s death was “a terrible tragedy” and not a crime.

“There’s no doubt Akai Gurley was innocent in this whole thing,” Brown told jurors. “But you all promised not to let your emotions get in the way.”

Brown tried to hammer home how dark the stairwell was when Gurley was shot and asked the jury if it was unreasonable for an officer to have his gun drawn in a darkened stairwell of a dangerous place, Macedo reported.

“He didn’t hide. He went into the dark stairwell, got startled and that how we wound up here,” Brown said, as reported by CBS2’s Lou Young.

He also argued that even with his finger on the gun’s frame near the trigger, which is what Liang claims, it would’ve been very easy to have been startled and pull the trigger, Macedo reported.

To find that this freak accident was a crime, Brown said, would have a chilling effect on police officers all over the city when they need to take their guns out, WCBS 880’s Irene Cornell reported.

But Alexis disputed that claim and demonstrated for the jury the pressure it takes to pull the trigger. He said the gun would never go off on its own and said Liang was an officer who couldn’t handle his weapon, 1010 WINS’ Juliet Papa reported.

As for questions about why Liang didn’t radio for help right away, Brown said Liang did, but the radios weren’t working properly.

Liang took the stand Monday, speaking publicly for the first time about the incident. He testified that he was doing a vertical patrol in the stairwell with his gun drawn when he said he was startled by a sudden noise.

“I just turned and the gun went off — It happened so quickly, it was a split second,” he told the jury. “I thought the bullet just went off, hit the wall and that was it.”

Liang testified that after firing the shot, he beamed his flashlight into the stairwell and initially saw no one.

He acknowledged that he didn’t immediately report the shot. Fearing for his job, he bickered with his partner about which one would phone their sergeant.

Then he went looking for the bullet and heard someone crying. He followed the sound down three flights and saw Gurley lying wounded.

At one point, Liang sobbed on the stand as he described the bloody scene. After a long pause, he continued.

“I couldn’t believe someone was hit. I just broke down,” he said. “I was panicking, I was shocked, in disbelief that someone was hit.”

As he radioed for an ambulance, Gurley’s girlfriend, Melissa Butler, tried to resuscitate Gurley, following instructions relayed by a neighbor who was talking to a 911 operator.

Yet Liang did not try to help. He said he thought it would be better to wait for professional aid.

Prosecutors questioned that decision and sought to show that he had been trained in handling firearms and unexpected, risky situations. Outside court Monday, Gurley’s relatives called for Liang to be held accountable for what they see as a callous killing.

“He did not call 911 for help, he did not perform CPR, he did nothing at all to try and save Akai’s life that night,” Gurley’s mother Sylvia Palmer said. “Peter Liang, Akai’s death was no accident. You murdered my son.”

During closing arguments Tuesday, Brown said Liang wasn’t trained in CPR while at the academy.

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