The director of the city of Washington DC shelter at the time was fully supported the breed-specific legislations. Because statistics indicate that all breeds bite, critics of breed-based ordinances argue that legislation which targets one or even a few breeds may not reduce the number of dog bites or serious attacks. Breed is not a single sign of human aggression, it is only one factor to be considered in an evaluation of a dog's biting tendency. Several medical studies do not include breed as a relevant factor in biting causes, instead most list; sex, health, heredity, early experience, socialization and training, quality of ownership and supervision, and victim behavior. Despite legislation singling out pit bulls as human aggressive, a study cited by the Prince George's County, Maryland, Vicious Animal Legislation Task Force found that between 1988 and 1993, pit bulls typically ranked less than fifth among breeds most responsible for severe bites. However, fatal attacks do tend to more of a problem of specific breeds. From 1979 to 1996, dog attacks resulted in more than 300 human fatalities. More than twenty-five breeds were involved in those fatalities, but pit bulls and Rottweilers were responsible for a large number. Between 1997 and 1998, pit bulls and Rottweilers together accounted for sixty-seven percent of deaths related to dog bite injuries.
According to Huemer there is no national registry or database on dog bites or dog bite breeds such as dogs that have a higher chance of biting a person. There is no way to truly tell what breed of dog caused the bite unless they are DNA tested, this has led to dogs being labeled as possibly dangerous. The Humane Society and the CDC suggest that what is more important than the breed of dog is the treatment the dogs receive from humans including; training, and socialization. Proper socialization and training are key for owning a "dangerous" type dog.