The Arizona Daily Sun reports that Cpl. John Tewes delivered his resignation letter Friday.
Tewes was called Aug. 19 after another officer hit a loose dog with his police car.
Both officers decided the dog needed to be euthanized, but Tewes was concerned about using his gun in the neighborhood.
Authorities say the animal didn’t die after Tewes bludgeoned it and jumped on its skull.
Finally, he used a hobble, which is like a metal cable, to strangle the dog.
Tewes told investigators he regularly clubbed animals to end their suffering while he was hunting.
___ Information from: Arizona Daily Sun.