Pit Bull dogs cannot be trusted to not attack other dogs, or humans. They were selectively bred to double up on the aggression characteristics. If you have a pit for a pet, be very watchful if small kids other than yours are in your home. Toddlers like to hug animals, which puts their face in close proximity to the dogs face. 95 time out of 100, the dog will bite that person. They perceive that action as one which is challenging the dominance of the dog.
The reason pits are being legislated is because of their aggressive reputations. They, rottweilers, & doberman pinschers, share the honor of being seen as dangerous.
How would you feel if you weren't at home, your dog was, and there was no adult family member there, and lets say a good friend and her children stopped by, and let her self into your back yard. The kid, who likes dogs, went up to your pit, and wanted to hug it. Bam. The kids face gets seriously bitten, and will be fortunate if the dog stops there. Do you have good liability insurance?