U.S. Immigration and Customs Enforcement used solitary confinement at its detention facilities more than 14,000 times between 2018 and 2023, including one California immigrant detainee who was held for 759 days, according to a report published Tuesday.

The report found that solitary placements at ICE facilities lasted on average about a month. Nearly half exceeded 15 days.

Solitary confinement is used in ICE detention facilities as a form of punishment as well as to protect certain at-risk immigrants.

Human rights groups say the practice is harmful and should be scaled back dramatically at all U.S. prisons and detention facilities. The United Nations has called solitary confinement longer than 15 consecutive days a form of torture.

ICE in recent years has come under fire from state officials and human rights groups for its reliance on the practice, and a lack of proper oversight and monitoring.

The 71-page report — one of the most expansive looks to date into ICE’s use of solitary confinement — was conducted by researchers at Physicians for Human Rights, Harvard Law School and Harvard Medical School. It was based on internal ICE records at 125 detention facilities obtained through litigation under the Freedom of Information Act.

Researchers said ICE’s use of solitary confinement and the time periods involved were both on track to grow in 2023, though its data was only collected through Sept. 13.

“The harms are just so well established — they’re incontrovertible,” said Sabrineh Ardalan, director of the Harvard Immigration and Refugee Clinic. “That’s why the failure to make any significant change is shocking.”

ICE spokesperson Mike Alvarez said the agency places detainees in isolation only after careful consideration of alternatives.

“Administrative segregation placements for a special vulnerability should be used only as a last resort,” Alvarez said. “Segregation is never used as a method of retaliation.”

About 700 solitary placements lasted at least 90 days, and 42 lasted more than a year, according to the report.

The longest completed instance of solitary confinement was that of a Mexican woman held at Otay Mesa Detention Center in San Diego for 759 consecutive days until Dec. 2, 2019. Her placement was coded as “detainee requested” and the reasoning was listed as “other,” though the record also showed a disciplinary infraction for fighting, said Arevik Avedian, director of empirical research services at Harvard Law School.

Two other cases were longer, but they were not included in the report because they were still ongoing at the Northwest ICE Processing Center in Tacoma, Wash., as of Sept. 13 — for 817 and 811 days, respectively.

ICE standards generally limit disciplinary isolation to 30 days per violation. But administrative segregation, regarded as non-punitive and intended for the detainee’s safety, can be indefinite.

ICE didn’t list the isolated immigrants’ mental health status in every record. But in the nearly 8,800 records that did include mental health information, about 40% documented mental health conditions.

For people identified as transgender, the average length of solitary confinement was two months, researchers said.

Alvarez said ICE doesn’t place detainees in solitary confinement solely because of mental illness unless directed or recommended to do so by medical staff. Detainees are often placed there because they request protective custody, as a result of a disciplinary hearing or to quarantine if no medical housing is available.

Detainees with mental health issues are under the care of medical professionals, he said, and are removed from solitary confinement if they determine it has resulted in a deterioration of their health and an appropriate alternative is available.

About 38,500 immigrants were being held by ICE as of Jan. 28, according to TRAC, a nonpartisan research organization at Syracuse University. Two-thirds of those detained have no criminal record and many others have only minor offenses, such as traffic violations.

ICE has said it is moving to reduce its use of solitary confinement over the past decade.

The agency issued a 2013 directive limiting its use, particularly for people with vulnerabilities, such as disabilities or mental illness.

A 2015 memo emphasized protections for transgender people, specifying that solitary confinement “should be used only as a last resort.”

A 2022 directive strengthened protections and reporting requirements for people with mental health conditions in solitary confinement.

Detainees held in solitary confinement are isolated in small cells away from the general population for up to 24 hours a day and have minimal contact with other people. Prolonged solitary confinement is known to cause adverse health effects, including risk of suicide and brain damage.

In California, Gov. Gavin Newsom vetoed a 2022 bill that would have regulated and significantly reduced solitary confinement in jails, prisons and ICE facilities.

Watchdog reports have repeatedly identified failures in ICE’s approach to and oversight of solitary confinement.

In 2021, the California Department of Justice issued a review of ICE detention in the state, with comprehensive looks at three privately operated facilities. Cal DOJ found little distinction between the conditions for detainees in administrative isolation as for those held for disciplinary reasons. The agency also found that detainees with mental illnesses were held in solitary confinement despite the isolation worsening their conditions.

“Most detainees in segregation are in their cells for 22 hours a day and when they are allowed outside they are generally recreating in individual cages,” the California report stated.

The same year, a report by the Department of Homeland Security’s Office of Inspector General found that ICE failed to consistently comply with reporting requirements for solitary confinement. Investigators analyzed records from fiscal years 2015 to 2019 and found ICE hadn’t maintained evidence showing it considered alternatives to isolation in 72% of solitary confinement placements.

Citing that report, Democratic senators, including the late Dianne Feinstein and Sen. Alex Padilla of California, pressed ICE leaders about the agency’s “excessive and seemingly indiscriminate use of solitary confinement,” calling it a long-standing problem.

A 2022 report by the U.S. Government Accountability Office found that information about detainee vulnerabilities and explanations of what led to their placement in solitary confinement were inconsistent. The GAO analyzed solitary confinement placements from 2017 through 2021 and found that about 40% were for disciplinary reasons and 60% were for administrative reasons, such as protective custody.

ICE says facility staff are required to offer people in administrative segregation the same privileges as those in general housing, including recreation, visitation, access to the law library and phones. They could also spend additional time out of isolation socializing or doing voluntary work assignments such as cleaning. Privileges for those in disciplinary segregation vary based on the amount of supervision required.

But two dozen formerly detained people interviewed by the report authors described having limited or no access to phone calls, recreation, medical care and medications.

Karim Golding, 39, of Jamaica was detained by ICE from 2016 to 2021. At the Etowah County Detention Center in Alabama, which ICE stopped using in 2022 because of its “long history of serious deficiencies,” Golding said he spent nearly two months in solitary confinement after testing positive for COVID-19. He now lives in New York.

Golding said that during the height of the pandemic, as the facility allowed busloads of new detainees in without following proper distancing or isolation guidelines, he urged the staff to provide tests. He and other detainees submitted dozens of sick calls requesting tests.

When the staff finally complied, he and several others were placed in solitary after testing positive for the coronavirus. He said he believes the move was retaliatory.

Golding remembers sometimes spending 40 hours at a time in his dingy 8×10-foot cell with holes in the concrete walls and no access to a shower. The isolation was lonely, he recalled.

“I went to sleep one night and woke up suffocating in the cell,” he said. “I started to cry because there was no panic button inside these cells. There was no officer, anything for help.”

Two other detainees reached by The Times said they were held in solitary confinement at facilities in Texas and Louisiana for several days while on a hunger strike.

As a candidate, President Biden pledged to end the use of solitary confinement in federal prisons. He signed an executive order in 2022 promising to ensure incarcerated people are “free from prolonged segregation.”

Authors of Tuesday’s report called on Biden to phase out the use of solitary confinement in immigration detention.

“There is still time,” Ardalan said. “This is one legacy he could leave from his administration.”