People held by U.S. Immigration and Customs Enforcement, or ICE, were placed in solitary confinement 14,264 times in the past five years alone — a stunning figure that is likely an undercount, according to a new report co-authored by the Immigration and Refugee Clinical Program at Harvard Law School and Dr. Arevik Avedian, lecturer on law and director of Empirical Research Services at Harvard Law School, and partners at Harvard Medical School and Physicians for Human Rights.

The findings, which were released on February 6, provide a fresh look at how ICE has increasingly used solitary confinement in 125 detention facilities across the United States, despite the agency’s own policy and in contravention of U.S. and international law — and promises by President Joe Biden to curb the practice.

“Once we got the data, it was just shocking,” says Avedian. “Every single statistic we looked at was disturbing. It was saddening to see how many people have been mistreated in ICE custody.”

The research revealed that detainees spent an average of 27 days in confinement — with some being subjected to limited contact with others for a year or longer — when even 15 days in solitary confinement may qualify as torture, according to the team.

“This should be a call to end solitary confinement, period, and release people from immigration detention, especially those with underlying vulnerabilities,” says Sabrineh Ardalan ’02, clinical professor of law and director of the Immigration and Refugee Clinical Program.

‘The million-dollar question’

Referred to as “segregation” by ICE, solitary confinement can cause a range of serious health problems, including physical, mental, and psychological effects, says Phil Torrey, assistant clinical professor of law and director of the Harvard Law School Crimmigration Clinic. “We are talking about things like hallucinations, suicidal ideation, post-traumatic stress disorder,” he says. “These effects are amplified for communities that are vulnerable to begin with, such as those who are LGBTQ+ or people with mental health conditions. And these impacts can last a long time, even for the rest of one’s life.”

Report co-author Katherine Peeler, MD, agrees. According to Peeler, an assistant professor of pediatrics at Harvard Medical School and a PHR medical expert, “ICE’s solitary confinement practices inflict unacceptable and, in some cases, lifelong physical and mental health consequences. Many people seeking asylum and other immigrants come to the United States seeking safety only to be forced into a claustrophobic cell for weeks, months, or even years. ICE must end its use of solitary confinement.”

Use of solitary confinement is even controversial within the carceral system — and completely inappropriate in the context of immigration, says Ardalan. “Immigration detention is supposed to be nonpunitive. So, why is it being used? That’s the million-dollar question.”

“This should be a call to end solitary confinement, period, and release people from immigration detention, especially those with underlying vulnerabilities.”

Sabrineh Ardalan ’02, clinical professor of law and director of the Immigration and Refugee Clinical Program

Extensive use of solitary confinement violates ICE’s own policy, she says. A 2013 directive by ICE indicated that segregation should be used rarely, and only as a last resort, particularly for transgender people, people with mental health conditions, and others with special vulnerabilities.

“But these policies have no teeth, which has led to a significant lack of oversight and accountability for facilities in placing folks in solitary,” says Ardalan.

She adds that excessive use of solitary confinement also violates U.S. and international law, as well as a campaign promise made by President Biden in 2020 to end the practice in federal institutions. That point was echoed by co-author Tessa Wilson, a senior program officer at PHR.

“President Biden pledged to end solitary confinement during his 2020 campaign — yet the egregious use of solitary confinement is on the rise in immigration detention facilities overseen by Biden officials,” says Wilson. “Despite years of whistleblower reports, oversight investigations, and courageous activism by affected people and advocates, our report makes it clear that there has been no meaningful progress or reform over the past decade. The White House and Congress must act now to safeguard the health and rights of those in its custody by ending this barbaric practice for good.”

Unearthing the data

Torrey says that the Harvard Law Program began to investigate the use of solitary confinement by ICE after hearing from clients who had experienced it firsthand. “We wanted to figure out how frequently this horrific practice is being used in immigration detention facilities, and in which contexts — and whether ICE’s own policies were being enforced,” he says.

In 2017, the clinic began filing Freedom of Information Act requests and state Privacy Act requests, but many of their requests went unanswered, says Ardalan. Clinical students in the Program helped prepare litigation that successfully unearthed the data provided in October 2023.

“The clinic spent years seeking this data,” says Farris Peale ’24. “During the year that I helped with the FOIA litigation, it often felt like we were fighting an uphill battle, and we might never uncover the requested information. The findings in this report are shocking, and a clear call for change. And the difficulty in obtaining meaningful information about these systems, after years of effort, demonstrates a profound need for increased transparency.”

“When our program finally received government data on solitary confinement after a long litigation battle and months of waiting, I felt sick as I reviewed it and saw horrifying statistics, like how officials left an immigrant in solitary confinement for 727 days,” agrees Felicia Caten-Raines ’25. “I knew in that moment that I had information in my hands that the public needed to see as soon as possible, or else more immigrants would continue to suffer in silence. The weight of that realization empowered me with a vision of the important role that I can play as a student now and as a future lawyer.”

After analyzing a cache of data derived from six years of requests, litigation, and interviews with dozens of immigrants, the team discovered that the total number of placements in solitary confinement started increasing during the Biden administration. It also found that the practice is regularly used not just as a protective measure, but as punishment for a variety of infractions, some as minor as the use of profanity or consensual kissing, or in retaliation for filing a complaint.

Even more disturbingly, says Avedian, the data reveal that the average duration of isolation, at 27 days, far exceeds the 15-day threshold at which UN human rights experts consider solitary confinement to be torture. And Avedian warns that the team’s findings likely don’t capture the full extent of the problem. “We are reporting what was given to us, but based on comparisons with other governmental reports, we know there is a significant amount of underreporting not just in the number of placements, but also the length of stay in solitary confinement.”

The researchers hope that the new report puts pressure on ICE, Congress, and the Biden administration to drastically reduce the use of solitary confinement in immigration detention facilities.

“A phasing out of the segregation policy could include better oversight and enforcement, and more transparency in the data about who is in solitary, how frequently they’re using it, and the duration,” says Torrey.

Better yet, says Ardalan, ICE could end the practice immediately. “This feels like a failure at every level,” she says. “But at the end of the day, it’s ICE that’s deciding to hold people in detention and that is a decision that they don’t need to make. There’s no reason for this carceral system for immigrants to exist.”

Want to stay up to date with Harvard Law Today? Sign up for our weekly newsletter.