Shoot in the thigh and strike the femoral artery.
A somewhat loose fitting tourniquet so he can watch himself bleed to death. Maybe throw a little salt or rubbing alcohol on the would once in a while.
No reason he should go to prison on the taxpayer dime. Just let him die.
Surgical amputation of all 4 limbs, place them in a kennel with a bowl of water and food on the other end.