For corrections officials, recidivism and employment are two of the most important measures of former inmates’ success at re-entering society.

New Cornell research shows inmates who have spent even short periods of time in solitary confinement may face worse outcomes on both fronts.

“Being placed in solitary confinement substantially increases the risk of committing more crimes after getting released from prison, and may decrease the probability of employment,” said Christopher Wildeman, professor of policy analysis and management in the College of Human Ecology.

Wildeman and co-author Lars Andersen – both are researchers for the Rockwool Foundation Research Unit in Denmark – reported those findings in “Long-Term Consequences of Being Placed in Disciplinary Segregation,” published March 12 in Criminology.

The study offers one of the strongest assessments yet of how brief stays in solitary confinement – usually less than a week and sometimes as short as a day or two – may affect post-release outcomes.

Most research on solitary confinement has focused on the ethics and mental health impacts of long exposures in the most secure detention facilities, which can last years and even decades. Extreme as those conditions are, Wildeman said, many more inmates experience short stints in “the hole,” as they refer to solitary, as punishment for breaking jail or prison rules.

A common narrative, Wildeman said, is that pre-existing issues make certain inmates more likely to end up in solitary confinement and to commit more crimes after serving sentences. Those issues, not stays in solitary, more likely cause bad outcomes.

To get at that question, Wildeman and Andersen analyzed two sources of Danish administrative data. They linked detailed prison records from 2006-13 with registers providing demographic data about inmates before and after their release, including information about family life, educational background, mental health, and employment and criminal histories.

The researchers compared the trajectories of inmates who were placed in solitary with those who were not placed in solitary after committing similar infractions (most often possession of drugs or a cellphone).

“They’re very similar groups,” Wildeman said, “so it allows us to provide a stronger causal test than most research in this area has shown.”

Being placed in solitary confinement, they found, increased the risk of being convicted of another crime within three years after release by about 15%. That’s a “pretty massive” increase, Wildeman said, considering recidivism rates are already as high as 50% to 60%.

Regarding employment, the results were more mixed.

“Being placed in solitary probably marginally decreases the chance of being employed,” Wildeman said, “but the effects there are a lot less consistent.”

Mental health is the most likely driver of the increased risk factors, the authors suggest, citing research that has shown disciplinary isolation can cause psychological trauma in a matter of days. Other contributors could include disruptions to classes or job training resulting from solitary placement, or being labeled a “problem inmate” by correctional staff, which could reinforce a cycle of conflict.

The findings suggest that, in addition to ethical concerns, there are practical reasons for correctional officials to consider alternatives to solitary confinement, the authors said, such as fines, loss of privileges or extended sentences. Alternatives might be harder to implement in “supermax”-type facilities, Wildeman said, but are an option in most jails and prisons.

“Whether somebody goes in solitary confinement for a short period of time or gets some other sanction,” he said, “is a relatively quick, relatively easy thing that we can think about modifying in the correctional system.”

Understanding the potential long-term consequences of time in solitary is even more important now in the context of the coronavirus pandemic, Wildeman said.

“Knowing the magnitude of the harms associated with being placed in solitary is especially pressing,” he said, “as many correctional officials are currently weighing placing inmates in solitary confinement as a method for stemming COVID-19 infections in their facilities.”

The Rockwool Foundation provided funding for the study.