An interesting paragraph from The Executioner's Song by Norman Mailer, in which he seeks to explain why prison doesn't work.
"...the prison system was a complete socialist way of life... For twelve years, a prison [told prisoners] when to go to bed and when to eat, what to wear and when to get up. It was absolutely diametrically oppsed to the capitalist environment. Then one day they put the convinct out the front door, told him today is magic, at two o'clock you are a capitalist. Now, do it on your own. Go out, fiand a job, get up by yourself, report to work on time, manage your money, do all the things you were taught not to do in prison. Guaranteed to fail. Eighty percent went back to jail"
That sounds pretty plausible. Fortunately, the Liberal Democrats are proposing that training and work should be a compulsory part of prision life, so that at least when convicts leave prison they have the skills and experience necessary to find a job, and so begin a constructive life, rather than fall back in to the only life many of them have know - a life of crime.