Now, I am not entering into a petty argument over this. BUT if it was an indigenous animal, then it belongs to the State of Texas. It is my understanding through a little research that yes, you can high fence an area, yes you can purchase and transport and breed and innoculate deer inside of this high fence, but own them you cannot. Firing a weapon from a road, across a road, or within so many feet from a road is illegal. Trespassing is illegal. Unless the animal in question was an exotic, it was NOT stolen. It would be mighty hard to prove without dna that the animal shot, was raised by that ranch.
It was stolen because the rancher with the high fence can decide who hunts there.
