Following Trump administration expansion of mandatory detention policies, over 45,000 habeas corpus petitions have been filed in federal courts nationwide, with immigrants challenging the legality of their confinement. Analysis of cases in Iowa, Kansas, Missouri, and Nebraska found that habeas corpus filings have been overwhelmingly successful, with the majority of resolved cases resulting in bond hearings or release. The centuries-old legal mechanism, dating back to the Magna Carta, has become a critical tool for noncitizens fighting detention based on prolonged confinement, lack of bond hearings, or inhumane facility conditions.