I once put down a small buck a week after the last deer season. someone had shot its lower jaw off. I put it down and called the DWM and told her what and where. She thanked me for shooting it.
A couple years ago I saw a buck in the pond, he had a couple hundred feet of fence wire stuck in his antlers dragging through the weeds. He was about spent when I finally got to him with a wire cutter. He was on his side with only the tip of his nose out of the water. I cut him free and shortly thereafter he got up and walked out of the water. Never saw him again, and maybe he died. But, animals are quite tough, they can survive a lot more than we think.
To put it down, it had better be obvious and without a doubt that it cannot survive.
