5 min read


How Does a Dog Know If You Are Good or Bad?



5 min read


How Does a Dog Know If You Are Good or Bad?


Next time you have coffee with a cute guy you met at the mall take, your dog with you. It could save you a lot of heartache if your prince turns out to be a frog – or worse. 

Your dog is a great judge of character and will let you know what he thinks about this smooth-talking character. Not everyone knows that dogs can pick up vibes - and right about now, Fido's sending a message, “This guy's a loser, let’s go to the park!” You have to admit, us human are not always adept at seeing the sneer behind a smile, so how do our canine buddies know a bad apple before we do?


Signs Dogs Show When Someone is Bad

Dogs never fail to amaze us. They are bright, intuitive creatures who can sense bad from good.

How many people have you thought were kind of nice until somewhere in a friendship, marriage or workplace, their true colors were exposed? You kick yourself thinking you should have seen who they were, but their mask was effective and you were taken in.

Dogs are not easily conned by conspirators and can tell if a person’s not right. Need proof? A study in Japan showed how dogs understand humans and can tell if they are being tricked.

The BBC reported that researchers pointed to a container where there was food, then pointed to another container that had none. At first, the dogs were interested, but once they realized the pointing was designed to deceive - they wouldn’t respond to the cue. A new person was brought in to try the test again and at first, the dogs were happy to try. Once they realized they were being baited, the pups lost interest and wouldn’t respond. Our dogs are aware when you’re fooling them and easily lose trust.

Dogs like honesty and don’t like to be played. They are socially intelligent with a moral code and can spot a faker super-quick. We can add that to their impressive list of unique talents, like working with the police, military and as service dogs for the blind and deaf. Their heightened senses are a great gift to mankind, detecting cancer, earthquakes and, now we discover, deceitful people.

How would you react if your dog’s body language was on red alert when you meet someone for the first time? The person you are talking to seems okay and has shown interest in Toby, your fun-loving Terrier. You notice he seems restless and that’s strange, as Toby loves meeting new people but not on this day.

As the stranger leans forward to pet him, Toby backs away and lets out a little growl. You are surprised, and reprimand him gently, but still, Toby stays alert, staring out this guy. The stranger laughs and remarks that dogs usually like him, so whats up with your dog? Toby is usually a super-social pup.

The stranger goes to shake your hand and talks of meeting up at a café, but Toby has other ideas. He barks like he means it and starts pulling on his leash, whining as you try to pull him back. You’re thinking it’s time to go and bid farewell to the stranger as Toby starts to relax.   

Why was Toby behaving like this? What was he trying to say? Dogs are the Judge Judys of this world and are harsh critics when it comes to people with a loose moral code. We all get gut feelings when a person isn’t right. Toby can see past the façade.

Body Language

Signs your dog is sensing someone is bad include:<br/>

  • Growling
  • Staring
  • Barking
  • Whining
  • Guarding

Other Signs

More signs your dog knows a person is really bad are:<br/>

  • Putting Up Their Hackles
  • Acting Anxious
  • Backing Away From The Stranger
  • Pulling On Their Lead

The History of Dogs Judging Character


Dogs are super-handy when it comes to sensing a snake in the grass. They are eternally vigilant, while humans tend to let down their guard. Throughout history, dogs have been used to guard sheep, temples and homes - their bark and keen sense of danger have been a blessing to mankind.

The granddaddy of dogs is the legendary wolf, that lived in the wild long before dogs were our family pets. They have come a long way since the advent of domestication in Ancient Egypt and Greece. Yes, archaeological records cite dogs as being valued for their hunting skills and companionship - thousands of years BC! Now, dogs are truly integrated into the human clan and like most people, work for the good of all.

Our service dogs help people with asthma, epilepsy plus vision and hearing loss, while police dogs know instinctively who not to trust. These dogsters are trained to support people, but it's instinct that makes them so good at their job. We have a lot more to learn, as curiosity asks the question. “What the heck's going on in the canine mind?”

Dogs are courageous and so worthy of our respect as they suss out a person, sending them packing if they don’t measure up.

The Science Behind Dogs Sensing Good and Bad in People


A study at the Kyoto University in Japan revealed our pups are loyal to the end. Three groups were set up with owners and their dogs to test how protective a pooch can be. Dog owners were requested to open a box while their pups looked on. Two strangers were present in the room and the dogs observed in one group the stranger helped their owner, while in the other they refused. There were two people in both groups who did nothing at all, giving researchers a view of how the dogs would act to people being mean.

At the end of each experiment, the dogs were offered treats by the people involved. The results were truly enlightening, as some dogs blanked the people who had chosen not to help. This blows the lid off dogs only reacting to cues, as these were pooches making choices based on an emotive, social response.

This is the way we react when someone tries to trick a close friend. We go into bat, all guns blazing, supporting the person we care about. If we are asked to choose sides, we’d honor our friendship and stand by our friend's side.

Training a Dog to Sense Good and Bad in People


How do you train a dog to do something it instinctively knows?

It’s a natural instinct for all dog breeds to guard. Some are better than others, like the Rottweiler - originally bred by the Romans to herd cattle and protect them from thieves.

They are employed by the military and police for their confidence and strength and can be wary of strangers, but always loyal to the leader of their pack. Their instincts to guard make them a popular security-dog choice. They are trained to recognize intruders, but how much do they naturally know?

A woman was walking through Kruger National Park with her two Rottweiler pals when she was viciously attacked by a tiger. Her fast-acting dogs took on the tiger, which was eventually killed. Why do our woofers jump to our defense so fast? Is it their training or something else?

What makes a dog protect people it doesn’t know and risk their life in the process? Some researchers believe it is the empathy shared between people and dogs plus their domestication over time. 

An experiment by psychologists at the University of London put eighteen dogs to the test. The idea was to see how our canine pals reacted to their owners and strangers humming and pretending to cry. Most of the dogs felt compassion and tried to comfort all the people involved. They nuzzled their guardians and the strangers in an attempt to reassure their new friends. This was a clear case of empathy between canines and humankind.

We can teach our clever mutts to guard our property, catch the criminals and sniff out drugs, so how do we train them to sense a person is bad, instead of good?

It would appear that defending our honor from a person meaning to do us harm is something dogs do naturally and comes from deep within! 

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By a Japanese Chin lover Linda Cole

Published: 02/19/2018, edited: 04/06/2020

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