I agree with BOHNTR. Wardens here in Texas are given a power called Officers Discretion. I am assuming that other Wardens in other states have the same power. If they feel an animal is dying and will not recover, they have the power to make that call and put the animal down. Typically if an animal is put down they will give the meat to a family in need. The horns are another story. They typically go into a traveling showcase to be displayed over Texas at different shows.
Now the problem I do have and have never been told of an officer having this kind of authority, nor do I think they should have the authority, is that they be able to dispatch a deer because they think it will be poached. That is the most ludicrous excuse I could think of. To me, if they feel the deer has a high potential of being poached, they have the perfect bait to catch a lot of outlaws. I highly doubt this was the reasoning for shooting this deer. If it were and it was shot in Texas, the Warden would probably be looking for another job.
My 2 cents.