I agreed with Don Firth earlier: put them away, away from all human contact, for all human stimulus (I really like the bland food idea). But I go a step further: they disappear. After the sentencing there is nothing more heard about them, from them, to them. After death they are cremated and the remains used for fertilizer. Only if they are found innocent do they again become "real."

As for those who do less than murder: "do unto others as you would others did unto you." Beat someone, you are beaten in the same way and to the same injuries, and your medical treatment is delayed for the same length of time. Steal, and your property is sold and the value given back to those you stole from (no property? Well, bucko, looks like you're going to do some work for the community, at minimum wage, and THAT will be given directly to the victim after costs of maintaining you are deducted.). Hit and run? -- no problem, you're hit and nobody stops. Rape? -- well, you'll know what a "power crime" is, won't you?

If someone kills, that person is killed. Not by the state, but by the victim's next-of-kin, and in the same manner that the victim died, IF the n/o/k wishes to do it. Otherwise, the killer quietly disappears....

Or go back the Brehon Law and give everyone an "honor price." Kill someone and upon conviction you pay the victim's "honor price" -- or your relatives have to.

Lots of different things can be done....