Evaluating the Effectiveness of Supermax Prisons

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Executive Summary

Twenty years ago, super-maximum-security prisons were rare in America. As of 1996, over two-thirds of states had "supermax" facilities that collectively housed more than 20,000 inmates. Based on the present study, however, as of 2004, 44 states had supermax prisons. Designed to hold the putatively most violent and disruptive inmates in single-cell confinement for 23 hours per day, often for an indefinite period of time, these facilities have been lightning rods for controversy. Economic considerations are one reason—supermaxes typically cost two or three times more to build and operate than traditional maximum security prisons. A perhaps bigger reason lies in the criticism by some that supermax confinement is unconstitutional and inhumane. While proponents and opponents of supermax prisons debate such issues, a fundamental set of questions has gone largely unexamined: What exactly are the goals of supermax prisons? How, if at all, are these goals achieved? And what are their unintended impacts?

The Urban Institute, with funding from the National Institute of Justice, conducted a study to help answer these questions with the goal of creating a foundation that would stimulate more informed and balanced research and policy discussions about supermax prisons. The study drew on several sources of information—a comprehensive review of correctional agency and legislative documents, and theoretical and evaluation research on supermax prisons; interviews with legislators, corrections officials, wardens, and corrections officers; site visits to three states; and a national survey of state prison wardens. Among the study's key findings:

• Despite disagreements among some scholars and practitioners concerning the definition of a supermax, over 95 percent of state prisons wardens agreed with a modified version of the definition used by the National Institute of Corrections in its 1996 survey of state correctional systems. (The definition: 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.)
• In 1996, 34 states reported to the National Institute of Corrections that they had supermax prisons. Based on the Urban Institute survey respondents who self- identified as supermax wardens, as of 2004, 44 states had supermaxes housing approximately 25,000 inmates (Mears 2005, 7).
• Considerable differences of opinion exist about the stated or perceived goals of supermax prisons. Among wardens nationally, however, there is substantial (over 95 percent) agreement that supermax prisons serve to achieve at least four critical goals—increasing safety, order, and control throughout prison systems and incapacitating violent or disruptive inmates. There is less agreement about whether they improve inmate behavior throughout prison systems; decrease riots, the influence of gangs, or escapes; successfully punish, reduce the recidivism of, or rehabilitate violent or disruptive inmates; or deter crime in society.
• The logic by which supermax prisons achieve each of a range of goals remains unclear. Do such prisons, for example, increase system order, and, if they do, does the effect arise through incapacitation, general deterrence of nonsupermax inmates, or some other mechanism? Current theory and research provide little foothold for answering such questions as they relate to the diverse goals associated with supermaxes.
• Interview, site visit, and survey respondents, as well as published accounts in the literature, point to a wide range of unintended effects of supermax prisons. Some of them may be relatively rare or benign, but many, such as increased mental illness, raise substantial concerns. At the same time, respondents identified positive unintended effects of supermaxes, such as improving living conditions and outcomes for general population inmates; these effects might offset such concerns or at least broaden the justification for investing in supermaxes.
• States generally have not conducted benefit-cost analyses of their supermaxes prior to or after investing in them. It thus remains unclear whether the benefits of these prison facilities outweigh their costs. That uncertainty increases when unintended effects are taken into account.
• Balanced assessments of supermax prisons require reference to their full range of goals (weighted by the importance of specific goals to which some states may give greater priority), as well as to their unintended effects; alternatives that may be equally or more effective; and the political, moral, and economic dimensions of supermaxes as a correctional policy.
• Among the most critical unanswered questions about supermaxes is their effect on prisoner reentry. Are supermax inmates less or more likely to reoffend upon release from prison? To obtain housing and employment? To successfully reintegrate into families and communities? The literature to date is largely silent on these and many other critical supermax issues.

In keeping with the few previous studies of supermax prisons, the Urban Institute's research suggests grounds for skepticism as well as concerns about the fiscal and human costs of these new forms of correctional housing. At the same time, it is clear that states and wardens believe supermax prisons can be effective correctional management tools, and this belief should not be lightly dismissed. For these reasons, it is essential that policymakers and corrections executives support research that can help determine whether supermax prisons are, or are likely to be, effective. Since the goals may vary by state, evaluations likely should be conducted on a state-by-state basis. Such research need not be extremely costly. Indeed, where funds are minimal, considerable advances can be made through efforts to clarify the goals and logic of supermax prisons and to improve appropriate supermax operations.

Note: This summary draws on Mears (2005), "A Critical Look at Supermax Prisons," in Corrections Compendium.

Note: This report is available in its entirety in the Portable Document Format (PDF).

The nonpartisan Urban Institute publishes studies, reports, and books on timely topics worthy of public consideration. The views expressed are those of the authors and should not be attributed to the Urban Institute, its trustees, or its funders.

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