SuperMax

Supermax (short for: super-maximum security) is the name used to describe "control-unit" prisons, or units within prisons, which represent the most secure levels of custody in the prison systems of certain countries. The objective is to provide long-term, segregated housing for inmates classified as the highest security risks in the prison system—the "worst of the worst" criminals—and those who pose a threat to national and international security.

According to the National Institute of Corrections, an agency of the United States government, "A supermax is a stand-alone unit or part of another facility and is designated for violent or disruptive inmates. It typically involves up to 23-hour-per-day, single-cell confinement for an indefinite period of time. Inmates in supermax housing have minimal contact with staff and other inmates," a definition confirmed by a majority of prison wardens.

Leena Kurki and Norval Morris have argued there is no absolute definition of a supermax, and that different jurisdictions classify prisons as supermax inconsistently. They identify four general features that tend to characterize supermax prisons:

In supermax, prisoners are generally allowed out of their cells for only one hour a day (one-and-a-half hours in California state prisons); often they are kept in solitary confinement. They receive their meals through ports in the doors of their cells. When supermax inmates are allowed to exercise, this may take place in a small, enclosed area where the prisoner will exercise alone.

Prisoners are under constant surveillance, usually with closed-circuit television cameras. Cell doors are usually opaque, while the cells may be windowless. Conditions are plain, with poured concrete or metal furniture common. Cell walls, and sometimes plumbing, may be soundproofed to prevent communication between the inmates.

The United States Penitentiary Alcatraz Island, opened in 1934, has been considered a prototype and early standard for a supermax prison.

An early form of supermax-style prison unit appeared in Australia in 1975, when "Katingal" was built inside the Long Bay Correctional Centre in Sydney. Dubbed the "electronic zoo" by inmates, Katingal was a super-maximum security prison block with 40 prison cells having electronically operated doors, surveillance cameras, and no windows. It was closed down two years later over human rights concerns. Since then, some maximum-security prisons have gone to full lockdown as well, while others have been built and dedicated to the supermax standard.

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