Understanding the "One-Bite" Rule for Dogs

With about 4.5 million dog bites in the U.S. every year, it's no surprise that lawsuits over the resulting injuries are fairly common. But the legal consequences of a biting incident depend on where you live and exactly what happened. Some states automatically assume that an owner is responsible if their dog injures someone; others apply a negligence standard. Many states, though, use the so-called "one-bite" rule. Under this standard, an owner's legal responsibility depends on whether they knew—or should have known—that their dog might be vicious or dangerous.

In this article we'll explain the one-bite rule, discuss when and where it applies, and talk about other important factors affecting an owner's legal liability for a dog bite.

How Does State Law Usually Deal With Dog Bites?

Each state has its own rules covering owners' liability for dog bites and other injuries caused by pets. The two most common legal standards are:

• Negligence. In some states, whether an owner is legally liable for injuries caused by their dog depends on whether they took reasonable care to control the dog's behavior. Failure to take such care can make an owner negligent.
• Strict liability. In contrast, some states have "strict liability" dog-bite laws. This means that owners are legally responsible for injuries caused by their pets, and a victim doesn't have to prove that the owner was careless or knew the animal was dangerous. (We'll discuss below the defenses owners still have in strict liability states.)

What Is the One-Bite Rule?

Most states spell out their standard for dog-bite liability in their civil codes. However, some states still rely on the "common law"--the principles courts fall back on to deal with situations that aren't covered by written laws. The one-bite rule is a common law principle that makes an owner liable for an injury caused by their pet if--and only if--they knew (or should have known) that the pet was likely to cause that kind of injury. (Some states have also incorporated aspects of this principle into their dog-bite statutes.)

A previous biting incident can be used as evidence that the owner should have been aware of their animal's dangerous nature. But keep in mind that the name "one-bite rule" can be misleading. The rule doesn't mean that every dog owner is entitled to one "free" bite. Behavior other than a bite or attack can put an owner on notice that the dog poses a particular kind of risk (more on that below). If the animal goes on to hurt someone while demonstrating similar behavior, the owner—or the owner's insurance company—will probably have to compensate the victim for medical expenses and other damages.

On the flip side, evidence of a previous bite doesn't always prove that the owner should have known their dog was dangerous. The details of the earlier incident can be important. A Pennsylvania court, for example, found that a prior biting incident didn't demonstrate a dog's viciousness because the dog might have been responding to being kicked. (See example, Deardorff v. Burger, 606 A.2d 489 (Pa. Super. Ct. 1992).)

How the One-Bite Rule Combines With Other Legal Standards

When people talk about "one-bite rule states," they're generally referring to states that have no statutes covering liability for dog-attack injuries, and instead rely on common law principles including the one-bite rule. But some states with dog-bite statutes still use the one-bite rule in some situations.

For example, Oregon's dog-bite laws use a combination of the three basic liability standards. An owner's legal responsibility differs based on what they knew, how careful they were, and what damages the victim is seeking:

• Strict liability. Oregon dog owners are always strictly liable for a victim's economic damages.
• Negligence. Owners whose carelessness leads to an injury can be held liable for all of a victim's damages.
• One-bite. Owners who know--or should know--that their pets could be dangerous can also be held liable for all of a victim's damages.

Keep in mind, too, that even in "one-bite rule" states owners can still be held liable for negligence. The one-bite rule doesn't mean owners can only be liable if they knew their dogs were dangerous; it means that an owner can't be liable for an injury caused by their pet if:

• they didn't know (and couldn't reasonably have known) that their dog might be dangerous, and
• the injury wasn't the result of the owner's carelessness.

Virginia's common law dog-bite rules are an example of this dual approach to liability.

Which States Use the One-Bite Rule?

States that either use the one-bite rule exclusively, or include it in aspects of their dog-bite liability laws, include:

• Alaska
• Arkansas
• District of Columbia
• Idaho
• Kansas
• Mississippi
• Nevada
• New Mexico
• New York
• North Carolina
• North Dakota
• Maryland
• Oregon
• South Dakota
• Tennessee
• Texas
• Vermont
• Virginia, and
• Wyoming.

Keep in mind that state laws aren't always straightforward. As we discussed above, some states apply the one-bite rule to owners in some situations and not others. Other states incorporate some elements of the one-bite rule, but don't use it as the only factor in determining liability. In Georgia, for example, an owner can only be liable for injuries caused by their dog if they know the animal is vicious or dangerous, or they knowingly allow their dog to go off-leash. This requirement is similar to the one-bite rule, but in Georgia it's only one element of what a victim must prove to hold an owner liable. (Ga. Code § 51-2-7 (2025).)

In addition, some states that apply negligence-based on strict-liability standards to owners apply a version of the one-bite rule to non-owners. For example, under California law an owner is strictly liable for bites and can be liable for negligence if their dog causes other injuries. In addition, a California landlord can be liable for an attack by a tenant's dog if:

• the landlord knew the tenant was keeping a dangerous dog on the premises, and
• the landlord had the legal right to evict the tenant but failed to do so.

(Uccello v. Laudenslayer, 44 Cal. App. 3d 504, 118 Cal. Rptr. 741 (1975).)

If you've been involved in a dog-bite incident, either as the animal owner or the victim, remember to check your state's laws—and consider consulting an attorney—for the most current information about potential liability.

When an Owner Should Know Their Dog is Dangerous

Under the one-bite rule, judges and juries must consider whether an owner should have known their dog was likely to hurt someone. And, while most dog-bite incidents don't result in lawsuits, insurance companies will take possible legal liability into account when they make settlement offers.

Remember that every case is different—if you've been injured by an animal, or your pet has been involved in an incident, you should refer to your local laws and consider consulting with a qualified local attorney. But here are some of the factors courts, lawyers, and insurance companies may consider when interpreting the one-bite rule.

1. Has the Dog Bitten Someone Before?

A previous bite can be strong evidence that an owner should have known their dog was dangerous. But, as we discussed above, sometimes the details of the previous incident don't demonstrate that the dog acted viciously. For example, if a puppy nipped someone, the court may find that its owners weren't necessarily on notice that the dog was dangerous. (See Tessiero v. Conrad, 588 N.Y.S.2d 200 (App. Div. 1992)).

2. Has the Dog Displayed Threatening Behavior?

Even if a dog has never physically attacked someone, a history of threatening behavior may put an owner on notice that their dog is dangerous. For example, if a dog often growls and snaps at strangers who come near it when out in public then the owner could be liable under the one-bite rule. (See, for example, Fontecchio v. Esposito, 485 N.Y.S.2d 113 (1985).) But the behavior has to be genuinely threatening. If a dog just barks at strangers without menacing them, its owner will probably not be liable if it bites someone. (See, for example, Collier v. Zambito, 807 N.E.2d 254 (N.Y. Ct. App. 2004).)

3. Does the Dog Like to Chase People or Jump on Them?

Sometimes even playful behavior by a dog can put people at risk. For example, a large, friendly dog might be in the habit of jumping on house guests. If the dog knocks over and injures a guest, its owners might be liable because they should have known that the tendency to jump could be dangerous. (Drake v. Dean, 19 Cal.Rptr.2d 325 (Cal. Ct. App. 1993).) Similarly, the owners of a dog that likes to chase bicyclists or motorcyclists might be liable if that behavior results in an injury.

4. What If the Dog Fights With Other Dogs?

If a dog is gentle with people but has a history of fights with other dogs, that's probably not enough to put the owner on notice that the dog might bite a person. Courts usually recognize that canine society has its own rules, and the way a dog behaves around other dogs isn't a reliable predictor of how it will act toward humans.

The conclusion may be different, however, if a dog has been trained to fight other dogs. It's reasonable to assume that a dog that was trained to fight could pose a danger to people.

4. What If People Have Complained About the Dog in the Past?

An owner will almost certainly be on notice that a dog is dangerous if neighbors or others complain that the animal has threatened or bitten someone. But the nature of the complaints matters. In an Alabama case, for example, a court ruled that a dog owner didn't know (or have a reason to know) that his dog was dangerous just because a neighbor had told him the animal was a "nuisance." (See Rucker v. Goldstein, 497 So. 2d 491 (Ala. 1986)).

5. Do Courts Assume That Certain Breeds Are More Dangerous Than Others?

Generally, courts don't consider particular dog breeds to be inherently dangerous. Just because your dog is a German shepherd, for example, you aren't automatically required to treat it as if it might hurt people. (See, for example, Roupp v. Conrad, 287 A.D.2d 937 (N.Y. App. Div. 2001).) But some states allow municipalities to enact so-called breed-specific legislation that defines pit bulls and other breeds as dangerous dogs.

5. Are Owners Who Post "Beware of Dog" Signs Saying They Know Their Dogs Are Dangerous?

Don't worry that putting up a warning sign is tantamount to admitting that your dog is a menace, landing you in bigger trouble if the dog ever hurts someone.

First of all, the sign might help avoid bites from occurring in the first place—far more preferable than winning a legal battle over a bite later on.

Second, if you think your dog might hurt someone, there's almost certainly other evidence of the dog's dangerousness besides the fact that you put up a warning sign.

And third, many homeowners use these signs in the hope that they'll ward off trespassers, even if their dogs have no history of being dangerous.

Can a Dog Be Euthanized Because of a Single Biting Incident?

A pet dog can be impounded temporarily while animal control decides if it might pose a danger to the public (either because of its behavior or because of diseases like rabies). If your dog is impounded by animal control because it bites someone, remember that as the animal's owner you have the right to be heard before the animal is permanently taken from you or euthanized.

It is unlikely that an otherwise well-behaved dog would be euthanized after a single biting incident. Under California law, for example, an attack dog that seriously injures someone can be euthanized just for that incident. But it generally takes either two separate biting incidents or some other history of dangerous and aggressive behavior for euthanasia to be legally permitted in California.

Defenses for Owners of Dangerous Dogs

Even if a dog has a history of aggressiveness, its owner might not be liable for a bite or other injury depending on the specifics of what happened and the details of their state's law. A dog owner's legal defenses could include showing that the injured person:

• provoked the dog
• only encountered the dog because they were trespassing
• voluntarily assumed a risk of injury, or
• were injured as a result of their own carelessness.

Speaking With a Lawyer

As we've discussed, the rules on liability for an injury caused by a dog vary from state to state. And, in any state, the outcome in a dog-injury case will depend on how the law (both the civil code and state court decisions) applies to the particular circumstances. Whether your dog may have hurt someone or you've been injured by someone's pet, consider speaking with an attorney who can help you with your case.