I think we can do better than that, we have so many peddos in this country, far better we start putting them to good use before they expire.
How about power-generating prison-plants, purpose built with rat-like exercise wheels/ treadmills whereby they could generate clean energy?
They wouldn't be mistreated, they would be getting healthy exercise on treadmills while generating clean energy.
If they refuse to walk, partake, they lose their privileges, ie, books, computer, outdoor time time, TV, games etc.
Those genuinely incapable would serve the same life-sentence (never to be released) minus some privileges.