Most “pit bull” attacks aren’t even carried out by pit bulls. People/police just use that as a catch-all phrase for a large dog.
Everyone should try this:
http://www.pitbullsontheweb.com/petbull/findpit.html
I heard the director of a pit rescue group on NPR talk about this issue. She said that the media in Chicago reflexively identified any dog that had attacked people as a pit bull. In some cases they were relying on eyewitnesses because the dog was gone, in others the reporters saw the dog but failed to identify the breed.
She said one time she responded to a report of a pit bull attack by going to the pound to get the dog. When she asked the officers about the dog that had been involved in an attack the day before, they looked at her like she was nuts, then showed her the culprit: a Golden Retriever.