NEW YORK (CBSNewYork) — The partner of an NYPD officer facing a manslaughter charge in the shooting death of Akai Gurley resumed his testimony on Thursday.

As WCBS 880’s Irene Cornell reported, the defense scored major points in questioning police officer Shawn Landau.

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He had been called as the prosecution’s key witness, but painted a far more sympathetic picture of officer Peter Liang’s conduct after he fired the shot that killed Gurley in a stairwell of the Pink Houses in East New York back in 2014.

As justification for Liang having his gun out in the pitch black stairwell, Landau said they were almost guaranteed to find someone when they patrolled the roof landing in the complex, Cornell reported.

While prosecutors had previously argued that the two officers wasted time and did nothing to help the victim, Landau testified that Liang was shocked and couldn’t believe he’d shot anybody.

Landau described Liang as kneeling over Gurley and calling repeatedly on the radio before sitting against the wall and crying, Cornell reported.

In previous testimony Landau said after the gun went off, he and Liang didn’t know the bullet hit anyone as they went back and forth about who was going to call in the incident.

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“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, Melissa Butler, 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.

But Butler testified Liang never came to help or see what happened.

Butler said she heard a door open above them, heard a shot and ran, with Gurley collapsing on the fifth floor landing. She began sobbing 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.

Gurley’s family has brought a wrongful-death lawsuit on behalf of his estate and his young daughter. At an announcement of the suit in May, the girl’s mother, Kimberly Ballinger, vowed to “be in court every time to make sure that justice for him is kept, that justice for him is received.”

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Liang faces up to 15 years in prison if convicted.