CAMBRIDGE, Mass. (AP) — A Harvard Law School clinic has sued federal immigration officials for failing to release records about the use of solitary confinement in immigration detention facilities.

The Harvard Immigration and Refugee Clinical Program said in a lawsuit filed in Boston federal court that it submitted records requests to the U.S. Department of Homeland Security and U.S. Immigration and Customs Enforcement, but the agencies haven’t fully complied in more than four years.

The Cambridge-based clinic said immigrant rights advocates have raised concerns over the use of solitary confinement on vulnerable immigrant populations, including LGBTQ individuals and people with disabilities.

“There is clear evidence that longterm solitary confinement has devastating effects, particularly on trauma survivors,” said Sabrineh Ardalan, the clinic’s director. “It is essential that we obtain these records in order to ensure that DHS is not continuing past harmful practices.”

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