gosh this sounds like a story someone told me, entirely oblivious of the implications, the other day. Their dog was put down for being vicious - bit repeatedly, finally drew blood.
On further enquiry, the dog was prone to what any vaguely interested owner would learn was resource guarding, especially unusual food and being on the sofa. Response to any growling? A wallop with a rolled up newspaper. Which caused dog to snarl, not growl. Which got it two wacks with the newspaper. This escalated to the point where the dog was lunging and the owner was using extreme force to restrain it - twisting its collar, hitting harder etc.
Finally - it nicked a chicken carcase and owner's relative went to take it off the dog. Which growled repeatedly, was shouted at and had the chicken grabbed. It bit and drew blood. It was put to sleep the next day.
On being told about Paddy biting OH the other evening - advised anything which would show Paddy "who was top dog". I have been so upset about that poor dog being PTS. And didn't even listen to the advice.
D