in the past few years, several internal committees and administrative bodies involved in the united states prison and legal systems have also begun to question solitary confinement's legality. in june 2012, for example, the us senate judiciary committee held its first hearing on solitary confinement. likewise, as of 2013, the us bureau of prisons has announced that it will conduct its first review of how solitary confinement is used in federal prisons. additionally, the us department of justice found multiple violations of the constitution and ada after investigating the use of solitary confinement for mentally ill inmates in two pennsylvania prisons. the us immigration and customs enforcement agency (ice) has also revised segregation procedures for detainees.