Prison doesn't work.
Community punishments do.
Prisons cost too much
Etc, etc etc.
I can assure you that if all were jailed for serious crimes, for persistent minor offending and breaches of court orders and they had to serve the bulk of their sentences in an austere institution singularly lacking in entertainment facilities - crime would plummet.
[Oh - and an added bonus, such prisons are CHEAPER!]
They are utterly wrong and then demand a cure of MORE OF THE SAME!