CLEVELAND — A police officer who climbed onto the hood of a car after a chase in 2012 and fired repeatedly at its unarmed occupants, both of them black, was acquitted of manslaughter on Saturday by an Ohio judge.

The trial of the white officer, Michael Brelo, following harrowing episodes in communities such as Baltimore, Staten Island and Ferguson, Mo., played out amid broader questions of how the police interact with African-Americans and use force, in Cleveland and across the country.

Officer Brelo, 31, was one of 13 officers who fired 137 rounds at Timothy Russell and his passenger, Malissa Williams, who were killed after a chase through the area on Nov. 29, 2012. Officer Brelo fired his Glock 17 pistol 49 times, including at least 15 shots after he reloaded and climbed onto the hood of Mr. Russell’s 1979 Chevrolet Malibu and the other officers had stopped firing.

The chase started downtown after reports of gunfire from the car; prosecutors said the noise apparently was the result of the car’s backfiring. More than 100 officers pursued the car for more than 20 miles at speeds that reached 100 miles an hour. They began firing when the car was stopped and cornered.