of course you can't blame a dog if their owner had any bad influence on them..i don't think dobies are killers at all.
i don't own one, but my uncle has had two (one died a few years after they got him ). their first dobie was such a sweetie! wouldn't hurt anyone ever. the one they have no gets excited very easily and she is a jumper but she is very playful. i love seeing her and she isn't the least bit scary it's terrible what some owners do to their dogs but i have never hard about that..