NEW YORK (CBSNewYork/AP) — A rookie NYPD officer testifying in his own defense got choked up while describing the moment he realized a man had been shot in a dark housing project stairwell in 2014.

Officer Peter Liang, who is accused in the death of Akai Gurley, took the stand at his manslaughter trial Monday.

Prosecutors said Liang fired his gun in a darkened stairwell of the Pink Houses in East New York, Brooklyn in November 2014, killing 28-year-old Gurley. Investigators say 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.

Liang said he had done hundreds of vertical patrols in the projects and it was at the rooftop level where he would generally draw his gun because that is where the danger was, WCBS 880’s Irene Cornell reported.

On the night in question, Liang testified that he did not have his finger on the trigger, and that he kept his finger on the outside of the weapon along the frame and pointed down as he was trained.

Liang testified he was startled by a noise as he opened the stairwell door, and his gun went off accidentally.

“I thought he bullet just went off, hit the wall and that was it,” Liang said.

He then went to look for the bullet and that’s when he discovered Gurley’s girlfriend leaning over him.

Liang recalls saying, “Oh, my God, someone’s hit!”

The officer said he called for an ambulance but was also “shocked” and “panicking.”

“I couldn’t believe someone was hit,” Liang told the courtroom. “I just broke down.”

Liang wept as he recalled his first sight of Gurley. He had to leave the witness stand for about a minute to compose himself before resuming testimony.

On cross-examination, prosecutors sought to show that Liang had gotten training in handling firearms responsibly and on handling dangerous and unexpected situations.

They questioned him about why he didn’t perform CPR on Gurley. They say Gurley’s girlfriend tried to do so, getting instructions from a neighbor on the phone with a 911 dispatcher. Liang says he had thought it better to wait for professional help to arrive.

“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,” Sylvia Palmer, Gurley’s mother, told CBS2’s Brian Conybeare.

Palmer said Liang murdered her son.

“Peter Liang, Akai’s death was no accident — you murdered my son. I need justice for my son. I need a conviction,” she said.

The defense says the fatal shooting was an accident, not a crime, and has argued that the officer didn’t know at first that the bullet had hit Gurley. Prosecutors claim the officer broke all the rules by having his gun out of the holster and failed to aid the dying victim.

Defense attorneys argued Liang was justified in having the gun out, because of the known dangers in patrolling the stairwells in a crime-ridden housing project. That argument was illustrated last week when two officers conducting a similar vertical patrol in the Melrose Houses in the Bronx were shot. The judge ruled defense attorneys cannot bring up that subject at this trial.

Last week, Liang’s partner, police officer Shawn Landau, and Gurley’s girlfriend, Melissa Butler, testified at the trial.

Butler said Gurley was visiting her apartment at the Pink Houses the day of the shooting and they decided to take the stairs because the elevator wasn’t working.

Butler said she heard a door open above them, heard a shot and ran, with Gurley collapsing on the fifth floor landing. The sobs came as she relieved the terrible moments — running for help, getting a neighbor to call the police, seeing the bullet wound in Gurley’s chest and trying to revive him.

When asked if she ever saw Liang, Butler said no, claiming he never came to help or see what happened.

Landau testified that he and Liang were both in shock after Liang’s gun went off by accident.

“I’m fired,” said Liang, according to Landau’s testimony.

Landau said he and Liang went back and forth about who was going to call in the incident. Landau said neither him or Liang knew the bullet hit anyone.

“We were just standing there,” Landau said.

Landau said by the time they made their way down the stairs to see what happened, they found Gurley with his girlfriend leaning over him, weeping. Landau said that Liang yelled out “oh my God, someone’s shot.” Moments later, he collapsed on the floor, crying himself.

Both sides rested Monday and closing arguments are scheduled for Tuesday.

The defense has asked a judge to dismiss the case, saying that the evidence doesn’t meet legal requirements for the charges. The charges accuse him of disregarding a substantial and unjustifiable risk of serious injury or death.

Prosecutors say the charges are justified.

State Supreme Court Justice Danny Chun says he’ll announce his decision after the verdict.

 

The Liang trial is being closely watched by advocates for police accountability, who see it as a counterpoint to decisions by grand juries declining to indict white police officers in other killings of unarmed black men, including those of Eric Garner on Staten Island and Michael Brown in the St. Louis suburb of Ferguson.

Liang is Chinese-American; Gurley was black.

If convicted, Liang faces up to 15 years in prison.

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