Ban the breed. Pit Bulls serve very little good purpose. Want a safe dog? Get a Yorkie. No offense to Yorkie owners out there, but I don't like the way that they look. I do however, like the way pit bulls look.
What the heck is the "purpose" of a Yorkie, anyway? Since you brought "purpose" into the discussion, it needs to be asked.
The purpose of a Yorkie is to bite your ankle, whereby you can shake it off. The purpose of a Pit Bull is for the phallic challenged to appear more masculine.