In the above situation,it's not your fault the owner was irresponsible enough to let the dog out, to run wild. My DH witnessed this once, after he had stopped a dog from biting him, on his bike, it promptly ran out and got run over by a truck.
I fully admit I am not an animal lover. I'm sure my "dog thread" is somewhere in the links posted above. I caused a big issue in my neighborhood when I suggested that owners need to use leashes, and just because they are nearby does not mean that their dog will not go after a cyclist. I stopped my bike, put it between myself and the dog (on a hill!), screamed loudly, "no, go home," and the dog still was very close to me for quite awhile. The same dog chased my DH and almost killed him going down the hill 2 years later. Someone witnessed the incident, brought the dog back to its owners (our neighbors) and we got a written apology. However, not much has changed.