Distinguishing between dangerous versus vicious dogs

     No clear legal distinction exists between "vicious" behavior and "dangerous" behavior in dogs. In appellate decisions the words are usually used interchangeably, and in civil litigation, attorneys frequently used the terms are without sufficient clarity. Behaviorally there needs to be a distinction, however.

     The motivational basis for the various kinds of aggressive behavior displayed by dogs (protective, territorial, pain elicited, predatory, fear-based, etc.) may be characterized as being either vicious or dangerous in nature. Vicious aggressive displays often consist of repeated, intense, uninhibited biting. Vicious behavior is always dangerous in nature but the opposite may not be true: that is, aggressive intent by a dog is not necessarily vicious.

     For example, most forms territorial aggression in dogs, frequently consist of no more than threats such as snarls and growls, or "inhibited" bites. Displays such as these may be reflective of a dangerous dog because such behavior suggests that a dog might bite, thereby possibly causing injury. In contrast, displays of vicious behavior are more likely to lead to severe injury and have the potential of being fatal. The defining elements in differentiating between the two are the form the aggression takes, the intensity of the bite (e.g. a single hard bite may be vicious) and how quickly individual bites follow each other (e.g. an attack consisting of a series of intense bites in quick succession may be deemed "vicious").