Pit bull owners are generally from the lower classes. Their attitude? “I may be on the bottom of the totem pole economically but on this sidewalk you are going to get off.” As for the fences-property dwellers have a special responsibility for children.
Having a fenced-in backyard for keeping dogs sounds responsible enough for me. It was a horrible accident, and we are too quick to accuse the dogs’ owners. IMHO, it is a parents’ responsibility to supervise their children, which had failed in this case.