More than 100 law school classmates of embattled Homeland Security Secretary Kirstjen Nielsen from the University of Virginia School of Law have signed a letter condemning the separation of migrant children from their parents and the indefinite detention of those families.

“The punishment you are imposing on families—on young children—is grossly disproportionate to the nature of the charge, and well beyond what is reasonable in a civil society,” reads the letter, signed by 110 UVA law alumni. “It is a cruel practice, one that may cause the children irreparable harm with lifelong consequences.”