7 or 8 years ago, we had pure bred border terrier that we loved. Rusty was a handsome and fun little dude. In the morning he would run into the room, jump on the bed, and literally dig the covers off me so he could lick me to death. He was obedient and loved people, and was great in every way, except... he had a very strong natural prey instinct, and that extended to small white dogs for some reason. On two occasions, we had to pry his teeth off of two dogs he saw and attacked, once in a training class. The first time my wife’s hand was cut badly and she given strong antibiotics that she’s still suffering effects from. The second time I knew he had to go. I could not afford the liability, and we are very fortunate no one sued us. We drove him back to the breeder in another state. My daughter, who worked in a vet clinic, said there was something mentally wrong with him that could not be fixed. He was never abused or mistreated. But he was not mentally healthy. If the breeder had not lived out in the country where he could run around without encountering strange dogs, he would have had to be put down. He suddenly died outside there shortly thereafter anyway. It was a sad time.
You are responsible for what the animal does now that you know he bites people. This is not a human being. A court can order to him to be put down anyway as a known danger, after he has harmed somebody else and you have been financially ruined. For the sake of others and yourself, he should be put to sleep humanely.
Sad story!
My neighbor had a similar experience - he bought a yellow lab from a breeder that became vicious after it left the puppy stage. It would come to our shared back fence and throw itself against the fence - snarling, growling and viciously barking. If the fence weren’t there, I kno’w he would have attacked me and my dogs. Never seen anything like it, yellow labs are usually friendly family dogs.
Neighbor finally took it back to the breeder, I don’t think he could control it. There was another one like that in my dog training class, a black lab that could not be controlled. The trainer said there was something wrong with the dog’s brain and to get rid of it ASAP.