I think he did everything possible to try and scare the dog off.And he even got bit trying to get out of his tree stand.I have never had to shoot a dog before either but you can bet I wouldn't be staying in my tree stand all night or untill the dog decided I could get down.I think he did the only thing he could under the cicumstances and he did take the dog to the owner and explained to him what happened.If anyone should sue it would be your brother for letting a dog run on your property and ends up biting people.