While shooting dogs is abhorrent to most people, there are some situations where it could be justified. In the eastern regions of NC where hunting deer with dogs is legal, some unethical hound owners will cut loose a poor performing dog, or one who won't leave the truck rather than feed it until next season. They just wait to the last hunt of the season and remove the collar, dumping the dog in the far reaches of a big bay,(Google Carolina Bays) These sometimes pack up and run deer until they're caught or shot by a property owner or lease holder.While a deer is quicker than a dog in the short run, a dog can run all day & into the night as long as it can get some water, and will run a deer down; believe it.
While I've never shot one of these dogs, I know many who have and I fully understand their decision.