Prison Overcrowding

With well over 2 million individuals confined in jails and prisons in the United States, it is easy to understand why the federal prison system and 24 state prison systems were above their rated capacity at the end of 2004. The data supplied by the Bureau of Justice Statistics revealed that the federal prison system had the highest rate of overcrowding in 2004 (140%), but this was only because states such as Alabama, California, Delaware, and Illinois housed a significant portion of their inmate populations in private and contract facilities. Local and county jails held 747,529 offenders in mid-2005, which represents approximately one third of the incarcerated population. These facilities were at 95% capacity, although this figure is deceptive because research indicates that smaller jails often operate well below their rated capacity, whereas larger metropolitan jails often operate well above their rated capacity.

Prison overcrowding is of particular interest in the United States, in part because of the number of people who are confined in American jails and prisons and in part because of several well-known court cases in which states have been ordered to improve the conditions of confinement to include alleviating overcrowding. However, prison overcrowding is neither a particularly new nor an exclusively American problem. With the advent of the prisoners’ rights movement in the early 1970s, prison conditions have come under increased scrutiny. One such area of increased scrutiny is the degree to which the inmate population exceeds the rated capacity of the institution in which it is housed. Furthermore, concerns about prison overcrowding extend beyond the borders of the United States. Canada, Great Britain, and the Scandinavian countries have recently raised concerns about prison overcrowding, and many nations in Africa, Asia, and South America have prisons that are more crowded than those in the United States.

Measurement of Prison Overcrowding

Prison overcrowding has traditionally been defined by density (i.e., the proportion of inmates to rated capacity of an institution; the ratio of single cells to multiple-person cells). A distinction can be drawn, however, between overcrowding and density. Whereas overcrowding is a psychological condition based on a perception of limited space by an incarcerated individual, density is a physical condition, such as the ratio of inmates to available space in an institution. There are two forms of density: spatial density and social density. Spatial density, the measure most often used in prison-overcrowding research, is normally calculated as the proportion of inmates in an institution or prison system to the available space as established by the rated capacity of the institution or system. Prison and jail officials often consider their institutions overcrowded when they exceed 80% of the rated capacity. Social density, on the other hand, is measured by the amount of double and triple bunking found in a correctional institution. Research indicates that inmate health problems and violence may rise as social density increases.

Causes of Prison Overcrowding

The overriding cause of prison overcrowding is fairly obvious: The number of inmates exceeds the spatial and social capacity of correctional institutions and prison systems to house these inmates. On the other hand, the underlying cause of this surplus of inmates is less apparent. Several sets of factors appear to have contributed to the growth of jail and prison populations in the United States and other parts of the world. One important factor, at least in the United States, is a punitive public. Many people in the United States want to see those who violate society’s rules punished for their actions. Politicians frequently comply with the public’s demand for greater punishment because they do not want to appear weak on crime. Accordingly, they introduce legislation that provides for mandatory, determinate, or longer sentences; reduces good-conduct time credit; and restricts or eliminates early-release programs such as parole.

In addition to the legislative response of politicians and policymakers to a punitive public, there are several other factors that may contribute to prison overcrowding. Drug use is instrumental in a quarter to a third of all new jail and prison admissions and is the leading cause of parole and conditional release violation. As such, drugs are both directly and indirectly (harsher sentences for drug offenses) linked to prison overcrowding. Demographic changes contribute to prison overcrowding, as exemplified by the crime explosion of the mid-1960s when the baby boomers were in the age range most conducive to crime (late teens to mid-20s). Over time, prisons age and become less efficient; some may even be closed. This places an increased burden on existing facilities and adds to the growing overcrowding problem. With advances in technology, law enforcement may become more efficient, which could potentially increase the jail and prison populations and contribute to prison overcrowding.

Consequences of Prison Overcrowding

The most frequently mentioned consequence of prison overcrowding is aggression. Early research on overcrowding in rodents indicated that mice and rats raised in a crowded environment were more violent, stressed, and diseased than mice and rats raised in an uncrowded environment. Studies conducted on prison overcrowding, however, have yielded mixed results. In some studies, prison overcrowding has been found to correspond to an increase in future disciplinary problems, particularly aggression. In other studies, prison overcrowding has failed to correlate with aggressive and nonaggressive disciplinary problems. In still other studies, prison overcrowding is associated with a noticeable decline in future aggressive and nonaggressive disciplinary problems.

There are several possible explanations for these inconclusive and sometimes anomalous findings. First, because younger individuals often have trouble avoiding getting disciplinary reports in prison, it is possible that changes in the age structure of the prison or the practice of housing older and younger prisoners in separate facilities could influence the results of overcrowding research. Second, most of these studies overlook the positive or ameliorative effects that may reduce the negative impact of prison overcrowding. When researchers examine the effect of educational, occupational, and psychological programming on prison-based aggression, they frequently find that these positive pursuits can have a calming effect. Both these factors, age and positive influences, suggest that a systems approach should guide research on prison overcrowding.

Aggression and disciplinary problems may be the principal outcome measures used in research on prison overcrowding, but they are not the only possible consequences of overcrowding. Additional consequences of prison overcrowding include reduced recreation time for prisoners, decreased access to health and mental health care, poor staff morale, increased facility maintenance costs, diminished institution security, and fewer opportunities for inmates to learn trades and attend school. These consequences, as well as the possibility of a rise in future aggression, illustrate the importance of finding a solution to the problem of overcrowding. A solution may not be immediately forthcoming, but by paying close attention to the systemic nature of prison overcrowding a solution, or combination of solutions, may well be found.

Solutions to Prison Overcrowding

Potential solutions to the problem of prison overcrowding can be divided into three general categories: administrative responses, front-end strategies, and back-end strategies. The most common administrative response is to build more prisons, although this is an expensive proposition that may fail to produce its desired effect. Prison construction will have little impact on prison overcrowding if the problem resides with the jail and its inability to manage pretrial and short-sentence inmates. Other administrative responses that could potentially offer a solution to the overcrowding problem include converting existing prison and nonprison facilities into inmate housing units, double and triple bunking, transferring inmates to private or contract facilities, and achieving greater multiagency communication and cooperation.

Front-end strategies are designed to manage prison overcrowding by reducing the number of new inmates entering the prison system. One of the most obvious front-end strategies is to prevent crime before it occurs. Even when crime does occur, incarceration may not always be the best option. Diversion programs that call on the individual to perform community service and the use of special drug and mental health courts can relieve overcrowding by diverting individuals who commit nuisance and petty crimes away from the prison system and into programs tailored to their individual needs. House arrest, intensive probation supervision, and drug surveillance in lieu of incarceration are additional ways to manage first-time offenders convicted of nonviolent crimes without resorting to incarceration and adding to the already burgeoning correctional rolls.

Back-end strategies help reduce prison overcrowding by releasing individuals from prison months or even years before their statutory release dates. Releasing inmates to halfway houses 6 to 12 months before their scheduled release can help ease prison overcrowding while maintaining some modicum of supervision over the inmate. If an individual does well in the halfway house, then the next logical step would be home confinement with monitoring provided by an electronic bracelet or similar surveillance device. Early release through parole is another back-end strategy capable of alleviating prison overcrowding. Allowing incarcerated offenders to earn good-time credit every month for good behavior, which would then move the offender’s release date up, is another example of how prison overcrowding can be reduced with a back-end strategy.

Future Research in Prison Overcrowding

Prison overcrowding research, practice, and policy could benefit from a number of alterations in how the field is conceptualized and studied. First, several researchers have recommended a systems approach to research on prison overcrowding. A systems approach would show that new prison construction may not always be the solution to prison overcrowding. Not only is new prison construction expensive, but it also fails to address issues such as pertinent overcrowded jails, excessive sentences, and distinguishing between those who require incarceration and those who can be managed in a less restrictive environment. The systems approach also suggests that resolving prison overcrowding will require cooperation and to some extent integration of the three primary approaches to reducing prison overcrowding: namely, administrative responses, front-end strategies, and back-end strategies.

Much of the research on prison overcrowding has taken a molar approach to the problem of overcrowding by using aggregate data from prisons or entire prison systems. Although this has shed light on the causes and consequences of prison overcrowding and pointed out possible solutions, it also has limitations. In recent years, researchers have called for more research on individual-level factors that may moderate the consequences of overcrowding. The few studies that have been conducted on this issue have produced potentially important findings, such as the fact that some white inmates, particularly those who were raised in rural areas, are more likely to perceive prison conditions as overcrowded than black inmates, who are often raised in more crowded urban environments. Another interesting line of research suggests that individuals who interpret or misinterpret behavior as aggressive are more likely to perceive the prison environment as overcrowded.

Adopting a systems approach to research on prison overcrowding and including individual-level moderator variables in the analysis may enable us to better understand prison overcrowding and its effect on the inmates and staff who live and work in correctional institutions and attain a firmer grasp of how overcrowding can be effectively managed in the correctional environment.


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