I heard decades ago that prisoners will sometimes be recruited in exchange for reduced sentences, but not sure if that was the United States or elsewhere.
Edit: I hope I am not spreading a myth further
Edit: I hope I am not spreading a myth further
True, it has been done in the past, but there are many... many horror stories associated with the practice [1].
[0] https://www.ecfr.gov/cgi-bin/retrieveECFR?gp=&SID=83cd09e1c0...
[1] https://en.wikipedia.org/wiki/Experimentation_on_prisoners