It may be a mistake to see this as a failure of the prison system, though - after all, Foucault was very interested in how systems achieve their wider function by not achieving their stated aims. The last part of Discipline and Punish is all about this - about how the carceral system produces delinquency, a break-down of social order that provides the pretext for continuing low-level intervention by the police. If this system of control is now moving from outside the prison into it, that's not necessarily a failure of the prison system, but rather a modulation of the way it functions.
--
"The slightly richer ... eat in semi-darkness, preferring
candles to electricity. These candles make me laugh. All the
electricity belongs to the bourgeoisie, yet they eat by
candle-end. They have an unconscious fear of their own
electricity. They are embarrassed, like the sorcerer who has
called up spirits he is unable to control."
-- Vladimir Mayakovsky http://blog.voyou.org/ voyou at voyou.org