I remember reading this story, maybe in the 1990s, where condemned prisoners were not killed, but their minds erased and their bodies put to work. Miners (or whoever needed) could rent such bodies to help them with their hard work.
This miner has three (or two?) bodies (definitely one male and one female) and uses a kind of remote control to command them. He wants to find a huge, legendary gemstone. But someone else, a rival, manages to interfere with the remote and turns the bodies against our miner. The interfering device was called an "override", as far as I can remember (I thought that was the title of the story; but couldn't find it...). Anyway, the miner manages to escape.
In the story it is explained that the bodies stank and were full of lice, because the owners found no use in commanding them to wash. I am not sure, but maybe their sentences were not for life, and after a while they were allowed to regain control of their bodies.