For most of the 20th century, prisoners' stays in solitary confinement were relatively short. "People would get thrown in 'the hole' for a couple days at a time, maybe a couple weeks at a time," says Craig Haney, PhD, a social psychologist at the University of California, Santa Cruz, whose research has explored the psychological effects of incarceration.
That's changed over the last two decades or so. "Now they're in the hole for years at a time," he says. Over the last 20 years, so-called "supermax" prisons have become increasingly popular. There, tens of thousands of inmates spend years locked in small cells for 23 to 24 hours a day, according to Jeffrey Metzner, MD, a clinical professor of psychiatry at the University of Colorado School of Medicine, and Jamie Fellner, a senior advisor with Human Rights Watch (Journal of the American Academy of Psychiatry and the Law, 2010).
The issue of solitary confinement is a complicated and controversial one. Different states and prison systems define solitary confinement conditions differently, so reliable statistics about its prevalence are hard to come by, as Michigan Sate University researcher Jesenia Pizarro, PhD, reports (The Prison Journal, 2008). But experts who study the issue agree that U.S. prisons are turning to solitary confinement more frequently.
"Some type of segregation has always been part of American corrections," says Joel Dvoskin, PhD, a forensic and clinical psychologist in Arizona. "What's new is that it's being used a lot more often."
As solitary confinement has become more common, so have questions about its psychological impacts. Chief among those questions: What really happens to people deprived of social contact for months or years on end?
Two types of solitary confinement are commonly in use today. The first, known as disciplinary segregation, is leveled as punishment when inmates break the rules. Steal a cellmate's radio, for instance, and you might be in solitary for a week or two. During disciplinary segregation, an inmate is separated from other inmates for a specified period of time.
The second type of confinement is known as administrative segregation, which is used when prisoners are deemed a risk to the safety of other inmates or prison staff. Prisoners in administrative segregation are placed into isolation units for months or years. Corrections officials first turned to this strategy in response to growing gang violence inside prisons, Dvoskin says. Though critics contend that administrative segregation has never been proven to make prisons safer, use of this type of confinement has continued to rise. That's worrisome to most psychologists who study the issue. Deprived of normal human interaction, many segregated prisoners reportedly suffer from mental health problems including anxiety, panic, insomnia, paranoia, aggression and depression, Haney says (Crime and Delinquency, 2003).
To Haney, evidence of these effects comes as no surprise. "It borders on being common sense, but it's common sense with a lot of empirical research that supports it," he says. "So much of what we do and who we are is rooted in a social context."
However, much of the evidence of harm comes from cross-sectional studies or research done on people who are not in prison, such as the isolated elderly. Designing a long-term study to follow prisoners in solitary confinement is challenging. Each correctional system is unique, inmates move in and out of segregation, and many states prohibit or limit psychological studies of incarcerated individuals due to ethical concerns.
In an effort to better understand the issue, Maureen O'Keefe, a researcher with the Colorado Department of Corrections, and Kelli Klebe, PhD, a psychologist at the University of Colorado, recently conducted a longitudinal study of the psychological effects of administrative segregation in a Colorado prison, with funding from the Department of Justice. The researchers studied 65 male inmates and 24 controls who were being evaluated at institutional hearings to decide whether they would be placed in solitary confinement or the general prison population.
Klebe and colleagues hypothesized that segregated inmates would show worsening psychological health measures over time, and that negative effects would be even more pronounced among inmates who had previously been diagnosed with a mental illness. To her surprise, neither hypothesis was supported by the data.
The researchers found that the segregated prisoners did show elevated rates of various psychological disorders, says Klebe, but she cautions that those symptoms are often present even before inmates enter administrative segregation. It's possible that inmates who are referred for a segregation hearing have a lot of psychological problems to begin with, she suggests, "and that's what's earning them the way into a lockdown situation."
Haney, however, argues that the study design had numerous methodological flaws, including the fact that all of the participants were initially exposed to a form of solitary confinement that the report acknowledges was especially severe. When prisoners were flagged for an administrative segregation hearing, they were immediately placed into disciplinary segregation until the outcome of that hearing. Therefore all study participants had been in confinement for several days to a week, according to Klebe, before they were ever evaluated by the researchers.
"I frankly don't think you can draw any conclusions from [the study]," Haney says. "There's very little doubt in psychology in general that enforced isolation is psychologically stressful and for some people will be harmful."
Meanwhile, in a growing number of states, mostly as a result of litigation, it's now illegal to place mentally ill individuals in administrative segregation. Still, mentally impaired prisoners are disproportionately represented in solitary confinement. O'Keefe estimated that in 2005, the prevalence of mental illness in administrative segregation in that state was greater than 35 percent, compared with a mental illness rate of less than 25 percent among the general prison population (Journal of Offender Rehabilitation, 2008).
That pattern is troublesome, says Metzner. "It's hard to give a reasonable argument that you can provide adequate treatment to someone with serious mental illness who's locked up in a cell for 23 hours a day," he says. "Our correctional system has become our mental health system for too many people."
Different individuals have different capacities for resilience, and even among people without mental illness, it's impossible to know who might be seriously harmed by extended isolation. Yet there are other good arguments for limiting segregation.
One is that most prisoners will eventually be released back into society. "Some people have told me they've been locked down so long they're fearful of their own behavior if they're around human beings," says Dvoskin. "That's especially counterproductive if you think this person is going to leave prison."
In 2007, researchers at the University of Washington reported that prisoners released directly from supermax prisons into the community committed new crimes sooner than prisoners who had been transferred from segregation into the general prison population for several months before being released (Crime and Delinquency, 2007).
Meanwhile, critics point out that supermax prisons are expensive and there's no good evidence that they're safer than the alternatives. Dvoskin says most psychologists who study confinement agree that at the very least, solitary confinement is used too much.
"We ought to be looking for any other way to keep prisons safe, including new ways that maybe haven't been invented yet," he says.
Kirsten Weir is a writer in Minneapolis.