Last thing you want to do is kill that dog. They’re supposed to be quarantined for 10 days or tested or your kid has to get shots. I don’t know what’s going on in Scotsboro but that’s the way it’s always been when I’ve had to deal with it. You don’t want that dog disappeared or dead because you need to make sure it didn’t have rabies.
As far as I know, the only way to test for rabies for sure is to put it down and send the head off (just like they would have you do with raccoon, etc.)
From what I am reading now, the current school of thought is that if a domestic dog, cat or ferret that appeared healthy at the time bites someone, it can be quarantined by the owner for 10 days and if it shows no signs of being rabid than the person does not need the anti-rabies prophylaxis. And that is not specific to any particular place in the US.