Your dog has bitten someone. Emotions are high. You may feel confused, shocked, angry, or afraid. Your thoughts may begin to run - what does this mean? Is my dog safe to live with? Why did this happen? And you might not have any good answers, compounding the already stressful situation.
This post will discuss why dogs bite, the importance and limitations of bite scales, how we assess risk in an aggression case, how we can reduce but never negate the likelihood of another bite occurring, and the options available when a bite occurs.
Why Do Dogs Bite?
Bites are communication, often coming after several other less-violent attempts at communication have been ignored or missed. Most often, dogs who bite are scared, fearful, or anxious at the moment and are asking desperately for space.
It's important to understand that all dogs are a bite risk. Any dog can bite in the right situation. Sometimes we imagine a black-and-white world with aggressive dogs on one side and non-aggressive dogs who-would-never on the other side, but that isn't reality.
More than 4.5 million people are bitten by a dog each year in the United States, and 1 in 5 require medical attention (dog bites get infected so easily, it's important to seek medical attention, especially if there are punctures.)
Children are the most likely demographic to be bitten, most usually by their family dog and most usually in the face (due to proximity). Family Paws Parent Education is a must-use resource for anyone with a dog who interacts with a baby, toddler, or child.
The truth is that aggression is a standard and functional behavior. It externalizes the "fight" in the "flight or fight" survival options. Whether a dog's brain tells them to fight, flee, freeze, fawn, or fidget depends on many factors, including the current environment, social support, and learning history.
Dogs may bite because they need space for their body when afraid, overwhelmed, or in pain. They tend to bite when their flight option is perceived to have been removed.
Dogs who bite are not bad dogs, and the guardians of dogs who bite are not bad people. Sometimes dogs bite their family members, and that doesn't mean the family has done anything to deserve being injured.
Whether or not a dog bites has very little to do with "training" in the way we often mean it. Whether your dog knows to sit and stay has nothing to do with whether or not they bite and are not generally part of the behavior treatment plan for a biting dog.
Many first bites occur during late adolescence or social maturity. We often see the warning signs in hindsight: A puppy who used to hold onto his bone or run away with it who now snaps when someone approaches as he chews, or a dog who would hide or cower when petted as a puppy now growls and bites to show their discomfort instead.
A dog who needs to bite may benefit from additional "behavior support," which I provide as a Certified Dog Behavior Consultant.
But that's a misdirect. The behavior is a symptom of a deeper issue involving communication, agency, the nervous system, and well-being.
Most often, dogs who bite are trying to create space. They deliver a single bite, most often with excellent inhibition. They want the threat to go away.
We'll talk more about inhibition and arousal in the next section.
Most dogs use ritualistic aggression beforehand, like growling, freezing, or hard staring. These behaviors are communication attempts asking for space. They say, "I do not want this to escalate. Please stop."
Before that, we often see signs of distress like licking the lips, yawning, and trying to look or move away from the perceived threat.
Some dogs jump over or quickly move through those warning signs. This can happen when a dog has massive physiological reactions to the stimuli; in other words, they go over their threshold immediately or quickly.
We often need to help these dogs create a "middle" by building resilience and the ability to self-regulate and decreasing the physiological response to the stressors.
Sometimes this is aided with behavior medication prescribed by a veterinarian or veterinary behaviorist.
Some dogs have been punished for growling or other showings of ritualistic aggression, so they no longer offer those warning signs (never, ever punish the growl!)
For these dogs, we often need to rebuild their communication skills. We want to teach them that we can hear them even when they are very quiet.
All dogs can bite, and frankly, given how closely we live with them while (generally speaking) knowing so little about their species-typical needs and communication, it's fantastic we aren't bitten more!
This is not to say that humans deserve to be bitten (although it is to say we should learn more about the animals we share our lives with). It is also to say that dogs are amazingly patient and peaceful, especially compared to humans.
Dog Bite Scales
Not all dog bites are created equal. An astronomical difference exists between a Level 1 bite and a Level 6 bite. But what does that even mean?
Pet professionals may use a Bite Scale to help them rank a dog bite's inhibition and arousal levels during a particular incident. Bite scales are essential but also limiting.
They do not consider context or bite history, which are vital in determining future risk. However, they do let us talk about inhibition in a dog bite while equalizing for size.
Two major bite scales (Dr. Sophia Yin's and Dr. Ian Dunbar's) are used most commonly and are similar. These bite scales are for dog-to-human bites. We use a different scale (Kara Shannon's bite scale) for dog-to-dog bites.
A Level 1 bite is not even a bite; it's a snap. There is no contact. This is the ultimate inhibited bite. A dog who snaps wants space for their body and does not want to escalate to violence to get that space.
It's important to know that snaps are intentional misses. Dogs bite faster than humans react - a snap is an inhibited gift, not proof of a person's impressive reaction time.
A Level 2 bite does make contact but does not puncture. Level 2 bites can still HURT, though. They can bruise and break the skin superficially (less than 1/10 of a centimeter).
Most dog bites are Level 1 and Level 2, making me think dogs have much more self-restraint than most humans!
A Level 3 bite is considered an "inhibited bite" too. Dogs have sensors halfway through their canine teeth (the four long teeth towards the front of the mouth). Those sensors say, "Okay, that's enough biting now." I think of these a lot like cat whiskers helping cats not to bump into things. The goal of the bite is not to maim or cause harm; it's the communication of a need for space.
We do distinguish between a Level 3a bite and a Level 3b bite. This difference has to do with arousal levels. A Level 3a bite is a single bite, while a Level 3b bite is multiple bites, of which one is at least a Level 3. Multiple bites indicate higher arousal levels.
The vast, VAST majority of dog bites are Level 3 or lower. A Level 4 dog bite (or higher) is no longer inhibited and, therefore, very dangerous. A Level 4 dog bite most usually occurs after the dog has practiced biting at a Level 3 multiple times (though not always - remember, bite scales don't give us context.)
Level 4 dog bites create punctures greater than half the length of the canine tooth. Any dog bite in which the dog bites and then shakes their head is automatically elevated to Level 4.
A Level 5 bite consists of multiple Level 4 bites.
A Level 6 bite means the person died. This is the case even if the bite delivered would otherwise have been classified as a low-level bite.
A Note on Other Factors that Influence Injury
Injuries must be assessed as they were before medical intervention. Medical intervention can actually make dog bites look much more gruesome after the fact. For example, tearing due to cleansing the wound should not be attributed to the dog.
Similarly, we do not include the medical treatment required in the bite assessment, choosing instead to look at the physical injuries themselves. This is because the chosen medical intervention can be wildly variable based on the medical professional's purview or the victim's health insurance.
The appearance of a bite and the injury sustained can also be affected by the mechanics of the bite, like when a dog jumps to bite and then comes down or when the victim pulls their body away.
Now that we understand why dogs bite and the nuances of assessing a bite, let's talk about how we assess risk.
When we assess risk, we are not just assessing the risk that the dog poses to the person they bit. We must consider the dog's well-being, the family and household members, and society at large.
Context is everything. When we can determine the function of the behavior, we can course correct to decrease the likelihood it will happen again. This might mean educating the family about canine body language to reduce misunderstandings or conflict, managing certain situations like mealtime to prevent the need to guard resources, or creating a plan for slower introductions to new people.
Most dog bites are preventable; a behavior consultant can usually help you figure out why your dog bit someone. It's important to note that up to 80% of cases involving aggression also involve some pain or discomfort that either directly or indirectly contributes to the aggressive incident. By and large, the pain is most likely to be orthopedic or gastrointestinal.
Of course, if a dog bites when in pain and is dealing with chronic pain, this can be a vital component of risk assessment. This is not dissimilar to medical history's role in risk assessment; comorbid conditions or some medications may increase the risk of a bite or decrease inhibition. These factors can make the situation more difficult to manage.
Management refers to the steps we take to prevent the dog from biting again (and more directly, to prevent the dog from again being in a situation where they feel the need to bite.) We work under the assumption that management will fail, and want to determine the risk to the dog, family, and society when that does happen.
Ideally, we can create a situation with low risk. In many contexts, something as simple as teaching the family to read dog body language, to intervene when their dog is uncomfortable, or to set reasonable expectations for canine behavior can resolve the conflict and lower the risk of a management mistake occurring.
Sometimes management is difficult due to the variety/quantity of the triggers, the environment, or a lack of resources (emotional, social, financial, etc.)
A dog who bites children is much easier to manage in a home with no children or child visitors.
A dog who bites when someone touches his food bowl during mealtime is much easier to manage than a dog who guards "stolen items" (because stolen items can be anything, this can be difficult to manage).
A dog who bites when afraid and is afraid of many things is more difficult to manage than a dog who has a single trigger that isn't part of her everyday life.
Manageability can also have to do with the predictability of the behavior. A dog with many triggers or triggers that are difficult to perceive (like not feeling well internally) may be much more difficult to manage.
Management can also be affected by factors like the size of the dog. If a large dog living in a city bites anyone within a 10-foot radius of them it may be more difficult to manage their stress levels and behavior than that of a small dog who can be carried in a hard-sided crate when they need to go out.
Within manageability, we have to discuss quality of life - for everyone.
For some dogs, the management required to keep them safe reduces their quality of life beyond acceptable measures. Don't get me wrong - behavior consultants are imaginative, creative, and resourceful. There are more possibilities than most folks realize. And while the quality of life doesn't necessarily factor into our risk assessment, it does pertain to the dog's well-being which pertains to our humane manageability.
Additionally, sometimes we can manage the dog's stress and anxiety but only at the cost of the well-being of the humans or other pets in the home.
Bite Levels are one piece of information I might share with my clients to assess risk. Still, often I will talk about the content without mentioning the levels and scales themselves, particularly because bringing up the scales means bringing up death by dog bite, and my general goal is not to traumatize or increase distress in folks who are already in an emotionally sensitive situation.
When I do bring up bite scales specifically, it's often in cases of high-level bites or otherwise worrisome bites, when a client wants a broader perspective on dog bites, or in cases with legal involvement.
Bite Levels touch on arousal, but to dive in further, a dog who is more highly aroused when they bite can pose a higher risk. In these cases, we may see less inhibition and multiple bites, which increase the likelihood of more severe injuries.
Beyond the bite scales, we also factor in the number of bites the dog has practiced. Because biting tends to be very reinforcing, the more a dog practices the behavior, the more likely it is to be used again when the dog feels the way they felt the first time it worked (most often, anxious or afraid).
The placement of the bite is also important in determining risk. Dogs are most likely to bite what is closest to them. Many bites occur to the arms and hands, the ankles or legs, or the face when the victim is a child or the adult has placed their face next to the dog's (context, context, context!)
It is especially concerning if a dog goes out of their way to bite the face or the core.
Similarly, when a dog "closes the gap" - or moves closer to a person to bite them - we should pay special attention. The wider the gap the dog is willing to close, the more concerning.
This sometimes overlaps with whether or not the bite was "provoked," which is the language we tend to see used when animal control or the legal system is involved. Of course, this can sometimes be very clear - like if someone hits a dog or hugs them - and sometimes less clear - like a dog who bites a visitor upon entry because the last visitor they met was loud and scary.
Switching gears, where the dog is developmentally, often comes into play in aggression cases. Dogs who begin biting when they are very young - before adolescence - display very unusual behavior from a developmental perspective. Conversely, such early intervention can mean bigger changes than we might see in an older dog.
When a dog is in adolescence, we must consider their brain is a current construction zone and how long that will be the case. Then we consider the changes that come with social maturity, too.
In senior dogs, we may be more likely to factor in the dulling of senses like hearing or sight, increased pain, or decreased mobility.
In assessing risk, we also consider the vulnerability of the people at risk of being bitten. Children and elderly individuals may be at a greater risk for injury, even with lower-level bites.
In some cases, when a dog bites a child or family member, especially in cases of repeated or high-level bites, the family may not be left with the option to keep both the child and the dog in the home.
This is not an exhaustive list of the factors we consider when assessing risk but gives us a good place to start.
Once we've discussed the risk, the family has to decide what to do next. It's important to understand that each individual, even within a family unit, will have a different idea of what constitutes an acceptable risk.
The options are as follows:
Manage the situation exclusively. An example might be a dog who snapped at someone when they woke her. The family says, "Our bad; we will no longer bother the dog when she sleeps."
Manage and train. Perhaps this same family decides not to bother the dog when she's sleeping but also wants to decrease her startle response and increase the chances of her choosing to move away when she is startled, so we both manage, and train.
Rescue/Rehome/Return. This option means the animal is rehomed, taken by a rescue group, or returned to the shelter or breeder.
Things can ethically get very tricky here. As contributing members of our society, it's important that we don't take a dangerous situation and make it someone else's issue. This is a vital message not only for pet parents but for rescues and shelters.
There are some situations where the dog's stress may not reoccur in a different environment, and this option may be appropriate. For example, if a dog is very pro-social with adults, but snaps at children, rehoming the dog to an environment with no resident or visiting children, may be appropriate. Depending on many factors, this may be less appropriate if the dog has already bitten a child.
Ethical rescues and shelters do not rehome dangerous dogs.
Another important consideration for the family rehoming their dog to consider: will the next family be able to give more, try harder, or care better about this dog than I can?
I often talk to families who have turned their lives upside down to help their dog, and it is impossible to believe a stranger will try any harder.
The dog's future well-being must also be a consideration when making these decisions. Once in another home, the original pet parents lose control of how someone may respond to their dog's aggressive behavior. The family may even be legally responsible for the dog's future behavior.
4. Behavioral Euthanasia. The final option is behavioral euthanasia. Often abbreviated as "B.E.," behavioral euthanasia refers to euthanizing an animal for behavioral reasons. We usually think of aggression, but folks may choose B.E. in cases of separation anxiety, canine cognitive dysfunction, or anxiety disorders where the dog flees or freezes instead of bites but whose quality of life is low.
B.E. is often judged harshly by those who have never been in such a terrible position.
Most people never want the power over life or death.
They want to grow old with their dog, take them on walks, and raise their children next to them.
To be put in a position where one must choose between their dog's life and the safety and well-being of that same dog, their neighbors, their children, or themselves is a terrible one, and folks in this position deserve nothing but love and support.
I have worked with families who ask if they should consider behavioral euthanasia because their dog growled at their child and families who have been bitten dozens, if not hundreds of times by their dog, before reaching out for help. And, of course, every variation in between.
Everyone who loves a dog who has been bitten is coming into this situation unwillingly. They come with their own lived experience, risk tolerance, and unique relationship with the dog. There are vast cultural differences - in some cultures, it may be par for the course to euthanize any dog who bites, while in others, there may be a much higher tolerance for aggressive behaviors.
Some people stop traveling or having visitors over; some postpone having children, and some move to new homes or even states to keep their dog while complying with legal rulings. Some people are forced to make an impossible decision and humanely euthanize their dog.
Each situation is unique, and the individual's risk tolerance is only one factor. But I want to honor all of these decisions - we are all doing the best we can with the information we have at the time.
As a behavior consultant, I never tell someone what decision they should make for their dog. My job is to help them understand their options and to make the most sense of the information we have available so they can make choices in an informed way.
All Together Now: An Example
Let's run through an example of an aggression case and break down these variables with a fake case study:
A 3-year-old, medium-sized dog bites a visitor in the face. The visitor sustains bruising, and no skin is broken. It is a single bite and the dog's first ever.
In my initial paperwork, I learn the dog can be nervous around new people, which I ask the guardians to operationalize. They say he tucks his tail, pins his ears back, and licks his lips.
They saw this body language as their guests arrived for the evening. Multiple people were in the room together, and I note that the room's layout may have decreased the dog's perception of flight options.
Additionally, I learn the bite occurred after several hours of visiting. They had walked the dog beforehand to try to tire him out, but because the dog had spent most of the walk reacting to the strangers he saw, he was actually more stressed and had less of a threshold to work with when the visitors started arriving.
Finally, after hours of socializing, someone went to hug him. At this point, the dog felt he had no choice but to bite. His tucked tail and pinned ears had been ignored, and he had nowhere else to go physically. He has been emotionally regulating and making decisions for hours and is cognitively exhausted. He lands an inhibited bite on the closest part of the human body, immediately displays more fear signals, and attempts to move away.
The pet parents immediately take him to another room and give him a chew to help him calm himself down and reach out for help.
So here we have a dog in social maturity with no bite history but a strong history of displaying stress signals around strangers. The bite is inhibited, and the location of the bite makes sense, given proximity. The dog's space was hugely invaded; there was no gap to close. The dog bit once, and then attempted to get away. Flight options were limited if non-existent, and the dog was trigger stacked from the walk and visiting for hours.
This dog also has a strong pro-social history with known people. It usually takes him 1-2 visits with someone to be completely comfortable with them. He is completely comfortable with his family members.
In this case, we have a good chance of preventing this behavior from occurring again. In this imaginary case, our management plan would involve a strategy for less stressful interactions with visitors (including options to disengage or leave totally) and on walks and incorporating consent testing into all interactions. Our training plan might involve building social skills and flight behaviors, desensitization and counter-conditioning, self-regulatory coping skills, and educating the parents about canine body language.
The risk of a bite happening again is not zero, but it can be low with proper management and understanding. The inhibition of the bite tells us that another bite is likely also to be inhibited (unless they start stacking up). Put another way; previous behavior is a good predictor of future behavior.
It's also possible that this family has tons of visitors all the time. The dog's fear of new people has been a stressor for many years, and the family cannot continue to live like this. This is a case where re-homing may be appropriate. There may reasonably be a person with more time or emotional bandwidth to address this concern who regularly has few or the same visitors.
If we change any of the variables in this pretend case it could quickly become unethical to rehome the dog, and behavioral euthanasia may be a more likely option. I hope this example does not become construed as a "how to" make this decision but rather demonstrates how we consider these variables together.
Dog bites are potentially more emotionally damaging than physically. They can evoke feelings of betrayal, anger, confusion, and helplessness.
Dog bites can result in PTSD and trauma symptoms for both the bitten and the witnesses.
We must increase the accessibility of appropriate behavioral and medical support for pet parents and increase pet guardians' knowledge of their pet's species-typical needs, behaviors, and communications.
If your dog has bitten someone, you're not alone. So has mine. Amore has a healthy bite record that has dwindled significantly over the years as I've learned more. You are not a bad pet parent, and your pet is not bad either. You are both worth more than the sum of your most terrified moments. Take good care <3