I'm a vet. Don't jump to a decision while you're red hot with emotion. One reason you shouldn't shoot your dog is because it is illegal. Any animal that bites someone legally becomes a rabies suspect and should not be killed so that the animal can be monitored for a period of time for progressing signs of rabies. Rabies is not common in the NW, but the law is the law. Variations in how to deal with observation/quarantine exist state to state and since I'm in Oregon, I will defer you to your vet. Besides, a bullet to the head is how we delt with these problems 30 years ago. I do think that euthanasia is appropriate in some of these instances, esp. when children are involved.