But when a dog attacks and kills or seriously hurts another dog, there should be a consideration of the circumstances, instead of just saying, well, he's just dog aggressive, no threat to people. (notably, though some breeds might be inclined that way, I don't know of any that are generally that out of control). Was it prey drive (killed the chihuahua), was it territorial? Was it provoked? Or is this dog incredibly aggressive towards other dogs, to the point of being a hazard to people who are minding their own business with their dog. So, the guy has a point, though not a very good one. Extereme dog aggression is scary, and should not be excused. However, I don't know many pitties that actually FIT that description.