You need to learn how to read statistics. This is FATAL attacks. Of course Rottweilers and Pit Bulls will have the largest numbers of deaths. Do you know how difficult it is for a Chihuahua to kill a person?

"Many small dog owners overlook their dog's behavior because they are small and/or think they cannot hurt anyone. The truth is, little dogs bite more than big dogs."
http://www.dogbite.org/pages/dogsmostlikely.html

I agree with the statement that it's how you raise the dog that matters. I have a large mutt that was rescued and definitely abused (18" burn mark down its back) and can tear a tennis ball into shreds in less than 5 minutes, yet it is gentle (even with small children and other animals), puts up with anything you can dish out (pulling tail, smothering its face, etc.), won't take a piece of food out of another person or animal's mouth or plate (I've tested it), and respects the toys of other animals and people by not using them unless offered. You will never convince me that breed is the cause of violent behavior in dogs, just as race isn't the cause of violent behavior in humans.

Oh, and for the record, I don't blame your father for shooting in self defense. That's completely justified in my book.