Negligence is the third legal doctrine under which a dog owner may be found liable for injuries caused by a dog. (The others are the one-bite rule and dog-bite statutes.) A dog owner who is unreasonably careless—negligent—in handling a dog may be legally responsible if somebody is hurt as a foreseeable result.
When it comes to defining negligence, broad rules are of little help. Whether or not someone acted negligently is a question that must be resolved based on the facts of a given situation. It comes down to this question: Did the dog's owner act reasonably, under the circumstances? If so, the owner wasn't legally negligent.
Here are a few examples of how courts have come down on the negligence issue in specific cases:
It's also possible that a dog owner will be found negligent for not taking special precautions to prevent a dog of a certain breed from causing injury. In at least one case, a court ruled that dog owners were responsible for an attack by their Rottweiler, even though they had no knowledge that the dog would be dangerous. (The case was in North Carolina, which has no dog-bite statute and generally follows the one-bite rule.) The court ruled that the owners were negligent because they should have known the "general propensities" of Rottweilers, which an expert witness at trial had described as very strong, aggressive, and unpredictable. (Hill v. Williams, 144 N.C. App. 45, rev. denied 354 N.C. 21, (2001).)
If a dog owner violates a law, and the violation leads to an injury, the owner may be negligent as a matter of law. In such cases, the injured person can win a lawsuit by proving only that the dog owner violated the law. The most common scenario is when a dog owner violates a local leash law by letting a dog run at large, and the dog bites someone or causes an accident. (For example, see Delfino v. Sloan, 20 Cal. App. 4th 1429 (1993), petition for review denied (1994), and Silva v. Micelli, 577 N.Y.S.2d 444 (1991).)
EXAMPLE: A California man let his dog roam, in violation of a local leash law. The dog ran into the road, and a pickup truck crashed trying to avoid it. Two men riding in the back of the truck were thrown out; they suffered serious permanent injuries. (Los Angeles Daily Journal, Jan. 26, 1987.) A judge ruled that the dog owner's violation of the leash law was negligence, and awarded the injured men $2.6 million. (The dog owner's insurance company ended up paying the whole amount, even though the owner's policy limit was $100,000. See "Dog Owners’ Liability Insurance.")
Violation of a law does not always mean instant liability for any injury that occurs as a result. For example, the owner of a Los Angeles hardware store violated a local ordinance requiring property owners to keep their sidewalks clean. As a result, a 70-year-old woman slipped on some dog droppings on the sidewalk and seriously injured herself. She sued the store owner. A jury found the owner 85% responsible for the accident and ordered him to pay $402,050. On appeal, a court ruled that the store owner's violation of the ordinance did not necessarily mean he was negligent. The ordinance did not impose upon property owners a duty to pedestrians, the court ruled. (Selger v. Steven Brothers, Inc., 222 Cal. App. 3d 1585 (1990).) Courts in other states have ruled differently.
Not all states allow someone injured by a dog to sue on a negligence claim. In New York, the only thing that makes a dog owner liable for injuries is knowledge that the dog might be dangerous (the one-bite rule); negligence is not a basis for imposing liability.
For example, a New York mail carrier sued for an injury she received while trying to jump into her car through the window to get away from a dog she was afraid would hurt her. The dog, which had been lying in its owner’s front yard while landscapers worked, had run toward her but stopped about six feet away. It apparently did not bark or threaten her. The court ruled that although the owner had been in violation of a leash law that required dogs to be leashed in spaces adjacent to public areas, that was irrelevant because it was only evidence of negligence. What mattered was whether or not the owner knew of the dog’s propensities to cause injury. In this case, the court ruled, there was no evidence that the owners had any knowledge that their dog might be dangerous, and that in fact the dog did not do anything vicious. (Petrone v. Fernandez, 12 N.Y.3d 546 (Ct. App. 2009).)