Is Your Dog Aggressive Towards People?
The term “aggressive dog” conjures the worst possible, scary images of dogs mauling defenseless children (thanks sensational news media and viral internet videos!). In reality, most aggressive acts perpetuated by dogs on humans are highly inhibited. And often, there is a “good reason” for the aggression, at least in the dog’s mind. Those events don’t tend to make the news. In my experience though, as soon as a trainer, behaviorist or vet uses the word “aggressive” to refer to someone’s dog, even if the dog has done nothing but air snap, the dog is labeled as aggressive and it becomes very difficult to overcome that.
Just to be clear, ALL dogs can behave aggressively. They all have the capacity to warn and inflict damage with their teeth. But very few dogs that engage in these behaviors on occasion should be labeled as “aggressive dogs.”
To gain some perspective on “aggression,” consider this: have you been able to go your whole life NEVER having an argument with another person, never raising your voice? Have you ever grabbed someone by the arm (or maybe as a parent, grabbed a child’s ear or spanked them) out of frustration? Chances are most of us have raised our voices, yelled, and possibly even grabbed someone out of frustration. Would you label yourself as an aggressive person, or would you just say there have been times when you’ve been angry or upset and acted out?
It’s less likely you have sent someone to the hospital with severe injuries as a result of a physical altercation, but some people have done just that. And others have killed. When you apply similar logic regarding aggression to human subjects, the occasional outburst, growl, snap, or even bite that doesn’t cause damage, is less scary and seems almost normal or reasonable. It still needs to be addressed, but it’s a much more approachable problem.
When looking at aggressive dogs, it’s important to look at the damage the dog has done first and foremost. This is exactly what Dr. Ian Dunbar’s Dog Bite Scale does. I have re-created it for you on this page for convenience.
Dr. Ian Dunbar’s Dog Bite Scale
This scale is an assessment of the severity of biting problems based on an objective evaluation of wound pathology.
Level 1: Obnoxious or aggressive behavior but no skin-contact by teeth.
Level 2: Skin-contact by teeth but no skin-puncture. However, there may be skin nicks (less than one tenth of an inch deep) and slight bleeding caused by forward or lateral movement of the teeth against the skin, but not vertical punctures.
Level 3: One to four punctures from a single bite with at least one puncture deeper than half the length of the dog’s canine teeth. There may be lacerations in a single direction, cause by the victim pulling away, owner pulling dog away, or gravity (e.g., a small dog that jumps up to bite).
Level 4: One to four punctures from a single bite with at least one puncture deeper than half the length of the dog’s canine teeth. May also have deep bruising around the wound (dog held on for some seconds and bore down) or lacerations in both directions (dog held on and shook head from side to side).
Level 5: Multiple-bite incident with at least two Level-4 bites or multiple-attack incident with at least one Level-4 bite to each victim.
Level 6: Victim is dead.
Interpreting Results from the Dog Bite Scale
From the same Bite Scale document, the below perspective and interpretations are provided by the author of the scale, Dr. Ian Dunbar.
Levels 1 & 2 Comprise well over 99% of dog incidents. The dog is certainly not dangerous and more likely to be fearful, rambunctious, or out of control. Wonderful prognosis. Quickly resolve the problem with basic training and classical conditioning and progressive desensitization handling exercises and bite-inhibition exercises and games. Hand feed only until this is resolved.
Level 3: Prognosis is fair to good provided that you have complete owner compliance. Treatment is both time-consuming and not without danger. Rigorous bite-inhibition exercises are essential.
Level 4: The dog has insufficient bite inhibition and is very dangerous. Prognosis is poor because of the difficulty and danger of trying to teach bite-inhibition to an adult, hard-biting dog and because absolute owner compliance is rare. Only work with the dog in exceptional circumstances. Owner should sign a form stating that they take responsibility and understand that
1) The dog is a Level 4 biter and is likely to cause an equivalent amount of damage when it bites again (which it probably will) and should therefore be confined to the home at all times and only allowed contact with adult owners.
2) Whenever there are children or guests in the house, the dog should be confined to a single locked room or roofed, chain-link fence run with the only key kept around the owner’s neck to prevent children or guests from entering the dog’s confinement area.
3) The dog is muzzled before leaving the house and only leaves the house for visits to the vet.
4) The incidents have all been reported to the relevant authorities.
Level 5 & 6: The dog is extremely dangerous and mutilates. The dog is simply not safe around people. I (Dr. Dunbar) recommends euthanasia because the quality of life is so poor for dogs that have to live in solitary confinement.
Causes of Human Aggression in Dogs
A lot of people I work with spend a lot of time trying to puzzle out why their dog reacted in an aggressive manner. While it is useful to understand the events surrounding a bite, often times the question “why?” goes unanswered. The good news is, we can usually address the issue even if we don’t know exactly what caused the event in the first place. Below are some common causes of aggression towards humans.
If your dog’s behavior fits neatly into any one of these explanations, great. If not, don’t worry.
The dog is startled out of sleep or is deaf or blind. Like a person that jumps when they’re startled, a dog may react when startled and often this results in a snap or nip. Take care not to startle a dog out of sleep, especially an older dog that may be hard of hearing. Don’t “sneak up” on a blind dog and touch him without making your presence known first. A vet check can confirm if your dog’s hearing or vision is impaired.
The dog is in pain and is reacting to being touched in a tender area. If your child rough-houses with the dog and smacks him on a hip that’s smarting already, your dog may react by targeting the child’s hand (or often, face, since the child is right at eye level). It’s not so much an intent to harm, but an impulse. Get your dog a vet checkup and treatment as necessary (chiropractic, pain meds., etc.) and control your children so they treat your dog in a more gentle manner.
The dog has a tooth problem. How often are you checking your dog’s mouth for abscessed teeth? Probably not often. But if your dog seems to become aggressive “out of the blue” or becomes reactive to pressure on his neck from a collar (such as when walking him), it’s possible he has a dental issue that needs to be resolved.
Hypothyroidism or medications. Aggression is a symptom of hypothyroidism in dogs. If your dog is 2 + years old and seems to suddenly develop aggression “out of the blue” get his thyroid tested. Some medications can also cause hypersensitivity and aggression in dogs. Check with your vet before placing your dog on any medications and make sure you understand (and can tolerate) the side effects.
The dog’s normal existence has him hovering at the edge of his bite threshold. All of us have a threshold for acting out. We can tolerate irritation, stress, anxiety, frustration to a certain point in our life, and then we either scream at the guy that cut us off in traffic or breakdown and have a good cry when we get out to our car and realize we have a flat tire.
Either one of these events, a flat tire or getting cut off in traffic, on their own we could probably handle without an outburst. But when coupled with sleep deprivation the night before, being under the gun to deliver on a big project at work, not having time to get to the grocery store so eating carrot sticks and raisins for lunch, and having a fight with your spouse earlier that day, and this last little event puts us over the top.
Some common stressors for your dog might look like this.
Stress stacking can happen to your dog too. It may look much like the graphic to the right.
If you’re a close observer and good reader of dog body language, you can almost always see when a dog is reaching his threshold.
Common stressors for our pet dog companions include:
- Physical pain and hunger
- Strange dogs that he’s being encouraged to socialize with on walks, at the dog park or at doggy daycare
- Being isolated from his pack (such as kept outdoors) or solitary (such as being left alone for long days)
- Family members that behave unpredictably (especially kids) or that have unpredictable expectations
- Unpredictable routines
- Frustrated instinct – e.g., a Border Collie being unable to herd
- Barriers and confinement (seen in “leash aggression” and “fence fighting”)
- Handling by owners, vets, and groomers
- Weather – heat, humidity, storms, change in barometric pressure
The dog is fearful. Sometimes referred to as “fear aggression” or “defensive aggression” this is a dog that is taking a defensive position to try to warn away an impending perceived threat. Often this response is observed when a dog is confined or restrained and knows they cannot escape. Consider the aggression you may witness at the vet’s office when a dog is being restrained for a shot, or when approaching another dog on leash.
The key here is successfully reading the dog’s body language and intentions. A fearful dog will have “retreat” body language. That is to say, while they may look for all the world like they’re big and mean, if you look more closely they’re terrified. Their ears are pinned back tight to their head, eyes are wide and you may see the whites of them, their center of gravity is leaning back not forward, they may not be facing the object of their fear head-on, but turned off to the side slightly, they may be licking their lips and their tail may be tucked or may be rigidly pointing straight out behind them.
There may be lots of barking and lunging if they’re on the end of a leash. This is all to try to keep you away because they don’t want you to advance. They aren’t confident at all. The dog is stressed, confused and just wants to get away from you or drive you away. Compare that to the next one.
(Inappropriate) Dominance Aggression. I qualify it as “inappropriate” because in my opinion a dog dominating a person is never appropriate. They shouldn’t do it by humping their human’s leg, hogging their furniture, or using their teeth. And yet there are some dogs that have such backwards relationships with their owners that they DO dominate interactions. When such dogs feel like their position is being usurped because the human deigned to make a request of them (“Fang, get off the couch!”) the dog reacts appropriately given the owner’s station compared to his. The human is the subordinate and subordinates don’t make demands in polite canine society.
If this is you, by the way, get a professional trainer involved immediately. As you continue to bumble around offending your dominant dog’s sensibilities you’re going to keep pushing him until he feels like he needs to “correct” you more forcefully. In these scenarios we often see the intensity of the aggression escalate over time and with less warning. Instead of a growl, the dog will just snap or bite. Their demeanor is usually pretty calm during these encounters, very matter-of-fact. There’s not a lot of bluster because they’re not necessarily trying to scare you away, they just need to correct and control you.
There is a very small percentage of dogs that are simply wired wrong. They react suddenly and intensely for no clear reason and with no provocation. The hallmark here is a dog that has an overblown response to nothing in particular. He may trot up to you wagging his tail looking for all the world like a friendly dog and then try to maul your face. If you have a dog that a trainer (or two or three) has assessed as being unpredictable and uninhibited in his aggression, you may have just such a dog. Typically the safest option is euthanasia. Clearly this isn’t a safe or enjoyable dog to live with, and in order to ensure that he doesn’t pose a threat to the community at large, you would have to manage him to such a strict degree that both of your lives would be pretty miserable.
How to Correct a Human Aggressive Dog
The other reason the scale above is handy is it allows me to frame this conversation, because there is a REAL difference between a Level 1 biter and a Level 5 biter. In the recommendations below I am referencing a dog in the Levels 1 & 2 categories, as explained above.
Get professional help. You didn’t think you’d get off so easy as to think I’d suggest you just deal with this yourself, did you? Of course you should get professional help. Your dog is threatening because he’s stressed and is coping with the stress by acting out. He may be fearful or he may think he dominates you. In either case, you need a professional to help you navigate the waters.
Implement NILIF. Nothing in Life is Free. Implement this protocol. It is beneficial whether your dog is fearful or dominant or just generally stressed. Check it out here: What is Nothing in Life is Free
Fixing Human Aggression in Dogs
Fixing this issue may require customized training that focuses even more on leadership, proofing, and desensitization. If you have a dog with a bite history, check out our different dog training options and contact us with your specific questions about how our programs will address your dog’s aggression.
Please Note: I am continually updating, adding to, and improving these “I Need Help With…” pages as I have time to do so in between training dogs and helping people offline. If you don’t see helpful information regarding this topic today, please check back again later. Or contact me so I can provide some recommendations and resources. Thanks!