NEW YORK (CBSNewYork/AP) — A tragic accident or a reckless act that cost a man his life?

That’s what a jury will decide in the trial of rookie NYPD Officer Peter Liang who is charged with manslaughter and other charges in the fatal shooting of Akai Gurley in 2014.

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Jurors returned to court Wednesday as they consider whether Liang accidentally discharged his weapon, as he says, or whether he acted out of recklessness and did little to help the dying victim, as the prosecution contends.

Jurors requested testimony of Liang and other witnesses, and worked through lunch on the first full day of deliberations.

Jurors tested the strength of the trigger on Liang’s gun in court – a dramatic scene as the trial continued, CBS2’s Lou Young reported.

The judge also denied a mistrial request made by defense attorneys.

Liang faces up to 15 years in prison if he’s convicted in the death of 28-year-old Gurley, who was killed when the officer fired his weapon in a darkened stairwell at the Pink Houses in East New York, Brooklyn.

Jurors were sent home at around 5:30 Wednesday evening.

Liang, 28, testified this week that he didn’t know anyone was in the pitch-black stairway on Nov. 20, 2014, when he unintentionally fired his drawn gun while on patrol after being startled by a noise. The shot ricocheted off a wall and hit Gurley, who was unarmed.

The 12-member panel deliberated for about an hour Tuesday before being sent home for the day. District Attorney Kenneth Thompson sat beside Gurley’s domestic partner, Kimberly Ballenger, as the jury heard closing arguments Tuesday afternoon.

Prosecutors presented a very different version of Liang’s state of mind after the shooting than Liang’s lawyer.

Defense attorney Robert Brown said his client was “very distraught” and radioed for help as soon as he knew someone had been shot. But prosecutors argued Liang was only concerned about losing his job and suggested that his initial attempt to find the shell casing from his gun was an attempt at a cover-up.

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“This finger along the side of the gun … will not slip off and find its way to the trigger,” Assistant District Attorney Joe Alexis said as held up Liang’s gun in court. “This was no accident.”

Brown cautioned jurors not to let emotions play any role in their deliberations.

“What happened here is a tragedy,” he said. “It’s a terrible tragedy. But it’s not a crime.”

Jurors are considering five criminal charges against Liang, which also include criminally negligent homicide, assault, reckless endangerment and official misconduct counts. Before beginning their deliberations, Brooklyn Supreme Court Justice Danny Chun dismissed one of the two misdemeanor official misconduct charges. After starting deliberations, the jurors asked for an array of materials, including a copy of the NYPD’s patrol guide.

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

Prosecutors say that Liang did not try to help Gurley, even as his girlfriend, Melissa Butler, tried to resuscitate him. Liang said he thought it would be better to wait for professional aid.

The shooting came in a year of protests and nationwide debate about police use of force, especially after grand juries declined to indict white police officers in the deaths of Eric Garner in New York and Michael Brown in Missouri. Both Garner and Brown were black and unarmed.

Gurley, too, was black. Liang is Chinese-American.

Liang faces up to 15 years in prison if he’s convicted of manslaughter and other charges.

Deliberations resume Thursday morning.

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