MILWAUKEE — A Milwaukee jury needed less than two days of deliberations to acquit a former police officer in the on-duty shooting of a black man last year that sparked two nights of violence on the city’s north side.

Jurors found Wednesday that Dominique Heaggan-Brown, who also is black, was not guilty of first-degree reckless homicide when he shot 23-year-old Sylville Smith after a brief foot chase following a traffic stop Aug. 13. Smith had a gun when he ran, but the case hinged on whether he was a threat when Heaggan-Brown fired the shot that killed him.

Body-camera video showed Heaggan-Brown shooting Smith once in the arm as he appeared to be throwing the gun over a fence. The video showed the second shot — 1.69 seconds later — hit Smith in the chest as he lay on the ground.

Prosecutors argued Smith was defenseless at the time of the second shot because he had thrown the gun over the fence. Defense attorneys argued Heaggan-Brown had to act quickly to defend himself.

Smith’s family members reacted angrily to the verdict, swearing and storming from the courtroom. Outside, one man shouted obscenities at a sheriff’s deputy as he was held back by other family members.

Later, his father, Patrick Smith, said the killing was “in cold blood,” but urged people not to react violently to the verdict.

Smith’s family filed a lawsuit against Heaggan-Brown and the city, family attorney David Owens announced after the verdict.