That is pretty much exactly the plot/idea of Unwind by Neil Shusterman. I'm serious. But, it doesn't work out as well as you picture. Corruption corrupts it. :)
HUH... IF THERE WAS A WAY TO MAKE THE DEATH PENALTY ALLOW THE SEPARATION OF THE BODY INTO VARIOUS BODY PARTS FOR MEDICAL PROCEDURES AND REASERCH INSTEAD OF JUST SLAYING CONVICTS, MAYBE WE WOULD HAVE LESS BODIES GOING TO WASTE, LESS GRAVES TO DIG. AND MAYBE LESS ZOMBIES TO DEAL WITH.