People, Reacher was certain about. Dogs were different. People had freedom of choice. If a man or a woman ran snarling toward him, they did so because they chose to. They were asking for whatever they got. His response was their problem. But dogs were different. No free will. Easily misled. It raised an ethical problem. Shooting a dog because it had been induced to do something unwise was not the sort of thing Reacher wanted to do.
Lee ChildI don't want to put the world to rights... I just don't like people who put the world to wrongs.
Lee Child