I have a lot of experience with shelters. Pit bulls are the most common breed in my city about 30% of all dogs - but they are about 50-60% of dogs in the shelters. They are an even larger majority of abused dogs and neglected dogs. This is because on average pit bulls have crappy owners. You don't find that many skinny bloodied up golden retrievers.

Any large dog can be unsafe. Large muscular breeds should never be left alone with children, and need to be trained in a way that does not cause aggression. This is not because they are more likely than other breeds to cause aggression, it's because their bites are deadly.

Point is, ban pits and we will soon have a big rotty problem. Or a big doberman problem, or german shepherd problem.

Denver and surrounding towns inacted pit bull bans - but with no effect on dog bites.