I would never keep a dog that bites people. Period.
Dog are supposed to be enjoyable animals. When they cease that function they have to go.
Civilly, you can be sued.
Criminally, you can be jailed for a vicious animal.
We grew up rural. When we got a dog after puppyhood, my father would give the dog food and let it munch a while and then slowly take the food from the dog, if it growled snapped or whatever it was history.
We had 14 dogs growing up, never had a biter or snapper