United Nations Standard Minimum Rules for the Treatment of Prisoners, 2015 (the Mandela Rules)
From the Rules' "Preliminary Observation 1":
The following rules are not intended to describe in detail a model system of penal institutions. They seek only, on the basis of the general consensus of contemporary thought and the essential elements of the most adequate systems of today, to set out what is generally accepted as being good principles and practice in the treatment of prisoners and prison management.
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