A 2025 analysis by Harvard University researchers and Physicians for Human Rights found that nearly 14,000 people were placed in solitary confinement in U.S. immigrant detention centers between April 1, 2024 and August 31, 2025.
August 31, 2025
high
temporal
Aggregate count of solitary confinement placements reported in ICE detention data as analyzed by the 2025 study.
The 2025 analysis noted that ICE detention data collections are typically incomplete, which likely results in an undercount of solitary confinement placements.
May 31, 2025
high
temporal
Methodological caveat reported by the analysts about the reliability and completeness of ICE-provided data.
A 2025 report found that detainees labeled as "vulnerable," including people with mental health issues, comprised about 20% of detainees between April 2024 and May 2025 and were placed in solitary confinement for an average of 38 days during January–March 2025.
March 31, 2025
high
temporal
"Vulnerable" is a classification used in the report to identify detainees with characteristics such as mental health conditions; the 38-day figure refers to the first three months of 2025.
The 2025 report documented that the average duration of solitary confinement for detainees labeled as "vulnerable" was 14 days in 2021.
December 31, 2021
high
temporal
Historical comparison provided in the 2025 analysis to illustrate changes in duration over time.