Can Dogs Sense “Bad” People?


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The internet is littered with anecdotes of people whose dogs knew somebody was bad news before they did. Is there any truth to claims that dogs can sense “bad” people? The short answer is yes, but only up to a point.
Studies have shown that dogs notice people who are unkind to their owners and hold a grudge against them. In one study, dogs were reluctant to take treats from somebody who refused to help their owner open a container. It’s one thing for a dog to remember somebody who already acted unfavorably toward their favorite human, but what about when they don’t like somebody they’ve just met?


There are several possible explanations for this. The leading theory is that dogs use their keen sense of smell to sniff out chemical changes in the pheromones that people emit that would indicate that they have bad intentions. Dogs’ exceptional senses of smell are already used to detect drops in blood sugar, potential bombs, drugs, and even cancer, so it should come as no surprise that dogs can pick up on other chemical changes within the human body.

When a person is acting aggressively, their brain chemistry changes in a way that dogs can smell, causing them to react to a potential threat before their human has perceived the threat. Unfortunately there’s a caveat – psychopaths experience few emotions, so their brain chemistry would be unlikely to change and give a dog warning about their bad intentions.

Another possibility is that because dogs are so in tune with humans, they are actually picking up on their human’s uncertainty and just reflecting back the person’s own anxiety about a situation.

The third possibility is that both dogs and humans have a sixth sense or a gut feeling about certain situations, but humans frequently ignore their gut instincts and dogs never ignore their intuition.

All in all, there’s probably a good reason not to trust anybody your dog doesn’t like!

Has your dog ever alerted you to someone with bad intentions?

Original source: Can Dogs Sense "Bad" People?
I love this kind of stuff, to read, to think about, but really what do we know? I think about 80% of our interpretations of dogs thoughts are just reflections/Projections on our own thoughts.

Has your dog ever alerted you to someone with bad intentions?
I'll never know because Asha alerts to everyone. :rofl: Funny/not funny - she is getting better with age & exposure but still... I do understand that she is over-reactive and would be a better citizen if she actually observed first and alerted second. I have come to understand how to read MY dog and I think everyone should understand their own dogs threshold, then go from there. That said, she has picked out a couple of people in an otherwise quiet public place that triggered her for some reason that I will never know.
I always trust our dogs instincts. I remember when Albert was a pup and I dropped in at work to introduce him to everyone. His little nub was going like crazy, then when one of the people almost no one liked came in, he he backed off and came back to me. The guy was even down on his knees trying to make friends but Albert wanted nothing to do with him.
Yes. I believe they have a sixth sense and just know.

I always watch Freyja’s demeanor when out and about. You can really tell who she like and dislikes and generally she is a very carefree Doberman.

Freyja knows me and knows me well. If she doesn’t like somebody, I truly believe it’s to protect me and I don’t question it.
Great topic and my answer is "yes"...but.

I've been trying to pay close attention "to the dog in front of me" as an individual vs my pre-conception of the breed, or dogs in general.

Vs "overly-mythologizing" (is that a word?;) about dogs instincts. Sort of a scientific study.

And notice Bonnie is very watchful, but not necessarily "knowing" about all things at 14 months. She's ahead in manners and socialization by traing, but she is still only half way to maturity, so "what should a teenager know" as an analogy, imperfect as it is comparing digs to humans.

So I have to model my behavior to help her distinguish between whats scary out of ordinary and whats something new that just spooked her, but part of our human being urban-suburban life. " Yes,Garbage truck is scary, but its ok", etc.

And learn to pick up her cues on what she might "know" or sense that I do not. Things like body language micro cues, early warning on dogs or people just over the hill, or something upwind...

She began alerting on people that "walk funny" as early as 6 months: elderly shuffling with cane, drunks, someone acting odd.

Things she can hear outside that I cannot.

Learning what her barks mean, and teaching her the neighbor taking out trash is ok, but accepting her valid alarm at the Amazon guy coming to the door...I want her to learn whats normal but not de-tune her so much that I mistakenly train her to suppress alarm at whats not.

Watching who she warms up to, and who she is reserved around...the development of her empathy, and comfort given vs her need for same, inbound.

When she needs affection, and when she gives it.

Its fascinating, and a co-creation in progress. Based on 60 years of dog ownership, my answer is I'm learning more how much I dont know.

And what she knows that I do not...
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Its fascinating, and a co-creation in progress. Based on 60 years of dog ownership, my answer is I'm learning more how much I dont know.

And what she knows that I do not...
Just wanted to say how much I love this. My first Doberman changed the trajectory of my life. She changed who I would meet, who I would relate to, and who would become "our people". She knew some stuff too that I didn't (and still don't).

As to the article, a couple thoughts: I think Katyusha has protected me from people who don't mind hurting others to get what they want, but not necessarily by alerting me. She protected me by just being there. Just by being a Doberman. Just by people seeing that she is situationally aware of everything in the room. I think for us in this crowd, it's worth remembering that (this is just my opinion) those who would do us harm are probably the ones most scared of a Doberman, thinking "ya that dog isn't going to take kindly to his person being victimized" . If you want to see a rowdy crowd of teenage boys start behaving better, watch them after they turn the corner and there's your Doberman staring at them.

But back to the ideas in the article: I agree here that dogs have a sixth sense and they use it. What I believe even more is that they are smelling it. not only the people who are bad operators, but the ones on the opposite end, the people who are excited and want to meet a Doberman (the OH MY GOD IT'S A DOBERMAN people) and the ones who just might need a minute with a dog. I honestly believe Katyusha smells people's emotional reaction to her and behaves accordingly.
I listened to a man whose background was in preventing child abductions/self defense training etc. He said the same thing about children; that they understand “that funny feeling” one gets when something feels wrong about a person or situation. He said adults lose that ability sometimes, or ignore it. I believe dogs do know when something is subtly out of the ordinary. We know too, if we only listen.
Great topic...I was walking in some woods years ago, with our female dobe at the time, and she kept kinda looking back without stopping our quick walk....then suddenly spun around, and stood squarely barking like I had never heard! I spun around as well, and a younger hispanic man (20's) was walking up behind us, and he completely froze. He was probably 20 ft behind us. I think she was aware of him the whole time, but it didn't bother her till he got too close. I didn't say anything to him, and we trotted right out of there. In my head at the time, I was so grateful that she was on alert; but later thought maybe he was just a kid cutting through there, and meant no any case, I was certainly glad to have my girl 'turn on'!!!
Learning what her barks mean, and teaching her the neighbor taking out trash is ok, but accepting her valid alarm at the Amazon guy coming to the door...I want her to learn whats normal but not de-tune her so much that I mistakenly train her to suppress alarm at whats not.
This, and other similar statements is where this breed has some vast differences. I had two "normal" Dobermans before I got Asha. They were both wonderful dogs, the second one had a little more suspicion and guarding than the first, but still a very trusting dog with strangers. I was reading a great article by Benchmark Doberman on nerve which they define as Thick/Thin as well as Strong/Weak. These are genetic traits but can be shaped and trained to a degree. By their definition, I would have to put Asha in the Thin Nerve end of Thick/Thin, meaning she will explode first and ask questions later. Thick nerve means very little suspicion even when a person acts weird or raises a threat. Strong/Weak nerve refers to standing up to pressure. A weak nerved dog can be intimidated easily into retreat, where as strong nerved dogs won't back down even under the biggest threat. And again, this can be shaped and trained especially for sport, but the dog needs a certain amount by genetics to work with.

I guess what I'm saying is that yes, I do believe our dogs know much more than we do at all times. Whether their judgement is valid 100% of the time is questionable. Ashas "thin nerve" is that she believes everything can be a threat and constantly looks for it. This makes an excellent watch dog in that she doesn't miss anything and isn't afraid to tell the world about it. She barks if the neighbor goes by walking his dog and there are 2 acres between our houses. I didn't train this into her and I can't train it out. My other two Dobes didn't have a hint of this kind of behavior.

Bottom line, once you really know your dog, how they act toward most people and when they are acting differently about one in particular, you should pay attention! The other thing I've noticed is that people who are afraid of dogs in general, your dog can tell that person is uncomfortable. Maybe they sense or smell adrenaline from them being nervous around a big scary dog, but does that smell different than adrenaline racing because that person is thinking about mugging you? I have a sister who has only visited once since I got Asha and she is terrified of all dogs. She tried to be polite and nice about Asha which went OK for a while but Asha was not warming up to her like she usually would. Asha really didn't want to be around her and grumbled and growled. I finally put her in in the truck (my sister was not staying at my house) to give them both a sigh of relief. I don't think Asha was even 2 years old then. Up until then, if we hung out with anyone for 5 minutes then Asha would "act normal" and accept them as part of our group.

Just as all dogs are different, all Dobermans can be different too.
Harley is on high alert & anxiety reactive all the time. We have a neighbor on one side of us that doesnt like him & he knows it (she doesnt appear to like me, either). He will bark & shake his ball at her every time she comes outside & when she is in her car pulling out of her driveway. Neighbor on the other side, he might bark once & ignores her, but she talks to him. They. Know. :dobe:;)
I always thought it might be scent detection as well as other factors. If a dog does the "sniff test" and doesn't like what they're smelling (i.e. changes in a BG's pheromone chemistry that might signal evil intent or aggressiveness, etc.) it might alert them. This, as well as facial expressions and body language. It's why, when meeting a new dog for the first time, I'll always go out of my way to smile and appear pleasant. I'll extend my arm/hand out just far enough for the dog to get a good sniff, but not so far that I can't retract it if they were to go cray-cray. If that is successful, then I'll extend my hand all the way out for them to "paw" me, if they know how. After that, then I might go for a little light ear rubbing. I try to avoid petting the head directly as that could be insulting to the dog. When it gets to know me better, then I can pet the head. And, if they want to lick my hand I'll let them. Even if they bark like crazy at me first, I stand my ground and I smile and then do the short hand/arm extension to give them that "first sniff."

It seems to work more than it doesn't.
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Flint seems to like some people right away and others not so much. I have noticed a pattern though: Men with the same build and body type as my husband he seems to like and trust more readily.

When I took him to work with me all of the time, he would growl and bark at big, burly, stocky men (my husband is built like a spaghetti noodle). Women he loves. Children he loves. Teenage boys he loves (maybe because they're either gangly or stinky!). Just not big stocky gym bros lol