While the vast majority of pet dogs never cause injury to a human, they all have that potential. There is a difference between using the term “dangerous dog” in conversation and using it in a legal context. The law has a specific definition for “dangerous dog” that varies depending on the city, state, and county where you live.
Banned Dog Breeds
Some places say that every dog of a certain breed is a dangerous dog under their law, and seek to ban certain dog breeds. In the United States, there are only a few places that consider every “pit bull,” for example, to be dangerous. If a dog of any breed is trained to attack people or animals or is kept as a guard dog on non-residential premises, it will also be deemed dangerous.
But most cities and states in America classify a dog as dangerous only as a result of that individual animal’s actions. For example, an unprovoked attack that causes injury or behavior that poses unacceptable risk might earn the designation. A dog that threatens a person with loud barking may be classified as dangerous in some places, but not in others.
What Is an "Unprovoked" Attack?
Describing a “dangerous dog” becomes even more slippery when looking at what constitutes an “unprovoked” attack. What exactly would you consider a “threat” worthy of a danger label?
A savvy dog owner realizes that the silent dog with lowered head, showing the whites of its eyes and stiffly wagging its tail is sending a clear message to keep away or risk a bite. Approaching this dog provokes an attack. But a child or uninformed adult might instead interpret the wagging as an invitation to approach and consider the resulting bite “unprovoked.” They might stare at the dog, pick up a toy that belongs to it, or wear a Halloween costume that scares the animal—all things that seem innocent to people but are indeed justifiable provocation to defend or even attack in the eyes of the dog, so it's best to know how dogs communicate.
The dog can be friendly yet still defined as dangerous. Overly playful dogs that jump up on a toddler or elderly person pose a risk. Even well-adjusted family pets can act with uncharacteristic aggression if caught up in the pack (mob) mentality of multiple dogs.
Multiple Factors Related to Dangerous Dogs
It would be so much easier to simply identify at-risk dogs by breed or other means, and then ban them. But there is no single factor to make this designation.
Dog bites—and the even rarer fatal dog attacks—always are a result of both the past and present events that include an array of factors. Some of these factors include the dog’s genetics, learned behaviors, socialization or lack thereof, canine function, health and size of the animal, reproductive status, individual personality, environment, owner responsibility, victim behavior, victim size, and physical condition, and popularity of the breed.
The More Popular, the More Potential Problems
Frankly, the more popular the breed, the greater the contact with larger numbers of people and that increases the potential for problems—as well as poor breeding typical of increased demand. Breeds responsible for dog bite fatalities have varied over time, in direct relationship to how popular the breed was at the time.
Today, the dogs that get the worst press include “pit bull” type breeds. But between 1975 and 1980, in one notable survey, the breeds most often associated with deadly attacks were the German shepherd, husky-type dogs, St. Bernards, bull terriers, and Great Danes.
The Ideal Dog
All dogs have the potential to bite. Well-socialized, emotionally and physically healthy dogs know how to threaten and protect themselves without risk to themselves or others.
Let’s put this in perspective. A comprehensive special report looking at dog bites and fatality statistics between 1979 and 1998 was published in JAVMA, Vol 217, No. 6, September 15, 2000. Interestingly, the information reveals that since 1975, dogs from more than 30 breeds have been responsible for fatal attacks on people, including the "gentle" breeds like Labrador retriever, West Highland terrier, and Cocker Spaniel.