Jack Russell Terrier being walked

Q. When we’re out on a walk, sometimes my dog is clearly anxious about certain people we meet. Can dogs tell when someone has a bad intent? I’ve felt on a few occasions that she may have protected me from a mugger.

A. People might have safer home lives and public outings if they listened more carefully to their dogs’ opinions. There’s no scientific evidence to prove that dogs have any kind of “sixth sense” about people’s intentions or personality, but there is certainly enough anecdotal evidence to raise an eyebrow. And why not? Dogs watch humans 24/7 and are highly sensitive to pheromones that we’re not even aware of, as well as subtle facial expressions or body language. It’s not crazy to think that our dogs could pick up on underlying evil intent or simply poor character.

That said, you have to take your dog’s nature into account. Shy or unsocialized dogs are unlikely to warm up to anyone, so you can’t always trust their dislike of a person. Guardian breeds such as Rottweilers, German Shepherds and Akitas may have a “family-first, family-only” attitude, so they may be inclined to be suspicious of strangers and don’t necessarily change their mind just because you welcome someone into the house. Another good possibility is that your dog is picking up on your own subconsciously expressed feelings or concerns about a person and is responding to that, rather than to any actual threat from the stranger.

But if your “I love everyone” dog takes what seems to be an irrational dislike to someone — well, you might want to have second thoughts about associating with that person. There certainly are accounts of people whose dogs expressed strong reservations about boyfriends, delivery people or guests that later turned out to be very accurate. Sometimes, your dog does know best.

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