www.prisonexp.org/slide-12.htm shows the effect of prison on guards and prisoners alike. Not a good thing for either of them. This demonstration was done in 1971 and for some reason has been basically ignored while we continue to deal with crime and punishment in the same old way; a very expensive way of making bad people worse.

www.youtube.com/watch?v=t2Q8XcwT5KM Book trailer video, 90 seconds.