Juliet Lyon, director of the Prison Reform Trust, has said closing small local prisons and replacing them with super-sized prisons "will not reduce crime or make communities safer".
She added: "The millions secured for new-build prisons could be more effectively spent on robust community service, treatment for addicts and care for people who are mentally ill."
She added: "Smaller prisons tend to be safer and more effective than larger establishments, holding people closer to home and with a higher ratio of prison staff to prisoners.
"Prison ought to be an important place of last resort in our justice system, not a giant economic regeneration or job creation scheme."
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