Dogs can tell when people are untrustworthy and will stop listening to a person if they prove unreliable.
Dogs may not seem bright when they're chasing their tails, but in many ways, they are clever creatures. In particular, they are very socially aware, both humans and each other.
Many studies have reported that they can sense human emotions. Recent research has found that they can tell the difference between happy and angry faces, and even show jealousy.
It now seems that they can sense when a person is untrustworthy. Once a dog has decided a person is unreliable, it stops following the cues they give.