Once, about 30 years ago. A friend and I were driving down a busy highway (US24) in Taylor, MI when we saw two "utes" crossing the highway with a small dog following them. We watched as one picked up a stick and threw it out into the lanes so the dog would chase it. It did, and got hit by a car. We made a U-turn and caught up to them and held them for police. The one wanted to fight and put up his arms. I thumped him a couple of times in the ribs and he stopped. When the police showed up, he complained to the police that his ribs hurt. The cop replied, "what you did was a felony and what those gentlemen did was made a citizens arrest. If they had to use force, too bad". They were such scum that the prosecutor offered to drop charges if the parents paid the dog's vet bills. They refused.
PS-the dog recovered.