Solitary Confinement in US Prisons: A Research-Based Primer
Picture of solitary confinement cell behind bars

A recent primer released by the Good Men Project, written by Clark Merrefield, is a response to estimates that on any given day, there are tens of thousands of prisoners held in solitary confinement in the U.S.

What is solitary confinement and why is it used?

The primer explains that solitary prisoners are typically confined to cells about the size of a parking space for 23 hours a day, except for an hour in a rec pen, an outdoor cage connected to a cell by a door. In this cell, there is a bed and a toilet, and some have two cement cubes attached to the wall, “forming an awkward chair and desk of sorts.” There are facilities across the country that leave the lights on all day and night in their solitary confinement units.

“The practice of holding a prisoner in solitary confinement falls under what is called restrictive housing, which the National Institute of Corrections — an agency of the Federal Bureau of Prisons — defines as ‘housing some inmates separately from the general population of a correctional institution and imposing restrictions on their movement, behavior, and privileges.”

The three situations in which prisoners are segregated from the general population and placed in solitary confinement typically include, but are not limited to protective custody, disciplinary segregation, and administrative segregation. Unfortunately, it is not uncommon for incarcerated individuals to be placed in solitary for reasons that are unacceptable, such as in retaliation for speaking up following assaults, or simply for being transgender under the guise of ‘for their own safety.’

Solitary confinement use by the numbers

  • Two recent analyses indicate 3% to 6% of U.S. prisoners are held in solitary confinement.
  • A national survey by the Arthur Liman Center for Public Interest Law at Yale Law School estimated 41,000 to 48,000 people in restrictive housing as of July 2021.
  • The survey covered 34 state prison systems and the Federal Bureau of Prisons, representing about 61% of the total prison population, with a median of 3% of people held in restrictive housing.
  • Ten jurisdictions reported leaving lights on all night in their solitary confinement units.
  • The survey defines “restrictive housing” as prisoners being held in isolation cells for over 15 days and for 22 hours per day on average, aligning with the United Nations’ definition of prolonged solitary confinement (Nelson Mandela Rules).
  • The Liman Center has conducted the survey biennially since 2013, providing the only ongoing, current national estimates on the use of restrictive housing.
  • There was a reduction of about half in restrictive housing since 2015, but there are caveats, including underreporting if isolation is for less than 21 hours per day.
  • During the early part of the COVID-19 pandemic, about 300,000 people lived in lockdown conditions similar to solitary confinement.
  • The Liman Center survey does not include estimates for prisoners held in solitary confinement in local jails.
  • Solitary Watch estimates about 122,000 prisoners were held in restrictive housing in mid-2019 across jails and prisons, approximately 6% of prisoners held in federal, state, and local facilities at any given time.
  • A recent analysis by NBC News found 11,368 out of 142,000 federal prisoners were held in restrictive housing as of September 2022, a 7% increase from May of that year.
  • U.S. Immigration and Customs Enforcement (ICE) detainment facilities can hold noncitizens in conditions similar to solitary confinement, with 14,581 segregated housing placements from 2017 to 2021, 40% for disciplinary reasons and 60% for administrative reasons.

The demographics of solitary confinement

A November 2020 report studied 184,183 prisoners in Florida correctional facilities from 2007 to 2015. The report found that long-term solitary confinement (over six months) is more common among younger, Black, and male prisoners. Prisoners in long-term solitary were more likely to have committed violent crimes (54.9% vs. 27.7%), have longer sentences (45.6 months vs. 31.6 months), be diagnosed with mental illness (28.9% vs. 15.0%), and require mental health services (31.1% vs. 16.6%).

A paper published November 2021 analyzed Pennsylvania prison records from 2007 to 2016, and estimated that 11% of all Black men in the state born from 1986 to 1989 had been incarcerated in solitary confinement by age 32. Racial disparities were evident, with only 3.4% of Latinos and 1.4% of white men from the same cohort being held in solitary confinement. About 9% of Black men in the state cohort were held in solitary for more than 15 consecutive days, which violates the United Nations standards for the minimum treatment of incarcerated people.

Solitary confinement is not an effective deterrent for future rule-breaking, according to one 2019 study. The analysis looked at data from over 9,000 prisoners who spent at least one day in restrictive housing, and found “no association between time spent in solitary and later infractions, both violent and nonviolent.”

The mental and physical toll

Well-documented consequences of long-term solitary confinement include both mental health problems, such as post-traumatic stress disorder, and physical issues, including musculoskeletal pain and cardiovascular hypertension. Research has also found that those held in solitary are at higher risk for early death. Prisoners who have spent any time in solitary confinement are 24% more likely to die, 78% more likely by suicide and 54% more likely by homicide, within the first year after their release from prison, compared with prisoners who never experienced solitary confinement, according to a 2019 study.

“Research also suggests a link between existing mental illness among prisoners and the use of solitary confinement. Prisoners with a serious mental health diagnosis, such as major depression or schizophrenia, are 170% more likely to end up in long-term solitary confinement, according to an analysis, published in 2022.”

The primer goes on to give a brief history of long-term solitary confinement, discuss the economic costs of, and dig into alternatives to solitary confinement. Read the full article based on recent and historical research here.