Breeds that have been portrayed as aggressive by media include bloodhounds, German shepherds, huskies, Doberman pinschers and pit bulls. However professional dog trainers, behaviorists, veterinarians and shelter workers agree that no particular breed of dog is more aggressive than any other and that factors such as diet, training, socialization, medical conditions, exercise levels, owner neglect and selective breeding can influence a dog's aggressiveness.
The public perceives pit bull-type dogs as threats because of sensationalized media reports of dog bites and attacks. However, further investigation of these incidents often reveal abuse, neglect or poor socialization. Pit bulls are often increasingly used as therapy dogs and service dogs. Pit bull dogs rescued from illegal fighting rings are often placed in families and thrive as pets. However, many municipalities have enacted breed-specific legislation banning the breed or dogs with a pit bull appearance, pit bull owners are denied tenancy, and owners of these and other types of dogs are required to carry extra liability insurance.
Herding-type dogs such as German shepherds are frequently used in police work due to their high intelligence and trainability.
A book that investigates the issue of breed-specific aggression is "The Pit Bull Placebo: The Media, Myths and Politics of Canine Aggression" by Karen Delise.