I broadly do not believe criminals can rehabilitate, they can learn to abstain from crime, yes - but I see no evidence suggesting the state of “rehabilitation” actually exists.
As far as I can see it, the concept of “rehabilitation” requires the criminal to have some sort of semi-permanent criminal mental state and then a dramatic conversion. I think this is nonsense. A criminal is, by definition someone who commits a crime - it is not a state of being. I think the concept of “rehabilitation” is simply an artefact of the liberal “blank slate” fallacy, applied to criminal justice.
Regardless, I do not believe it should be the role of the criminal justice system to rehabilitate offenders.
I recognise this is a considerable departure from our current orthodoxy, but I believe custodial sentences should be served in a “penitentiary” system, dispensing with “prisons”.
Essentially I believe custodial sentences should be for the purposes of 1. Public safety, 2. Punishment. Rehabilitation might come a distant 3rd in some cases.
I believe the true solution to this problem is root and branch restructuring of our justice system, much, much more severe sentences and a far more significant system of imposing life-altering fines, that are actually recovered - through a system similar to the current child maintenance recovery system - which I outline in detail here: Enhanced Criminal Fines Initiative
