An unleashed dog (also big) attacked my friend's dog, wouldn't stop and even drew blood. Her dog eventually fought back. The other dog was losing (got bloodied too) and would've gotten beaten the hell out of it if both dogs haven't been separated.
Since the other dog (the loser) was a bit more injured than my friend's dog but still put down, the other owner is still complaining and thinks my friend's dog needs to be taken away. Who is at fault?