I agree wiith Tazman, you ain't taking my deer, period. I will do anything in my power, short of landing in jail on a felony charge, to prevent this. If this means following you to your truck, getting your tag number, and showing up later at your house with my buddies, so be it. If this means pretending I agree, you did make the killing shot, then smashing you in the back of your head as you gut it, that's OK too. I'm no kind of tough guy, but I'll fight until I can't get up to prevent someone stealing anything from me, let alone my buck!
I'd do the same if I saw someone trying to steal from a kid.
All our deer are under lock and key for just this reason.