NEW YORK — The rookie police officer who shot an unarmed man in a dark public housing stairwell says what happened was a deadly accident.

Prosecutors call it manslaughter and say he acted recklessly and then did little to help the dying man.

Jurors will start discussing their views of Officer Peter Liang’s actions as soon as Tuesday.

Closing arguments are expected in the morning, and deliberations are likely to begin in the afternoon.

Liang, 28, says he didn’t know anyone was in the pitch-black stairway when he unintentionally fired. The shot ricocheted off a wall and hit Akai Gurley, 28, who was taking the stairs down rather than wait for an elevator.

Liang testified Monday that he was patrolling a dark stairwell with his gun drawn, his finger on the weapon’s side, when a noise startled him.

“I just turned, and the gun went off,” Liang said, explaining that his body “tensed up.”