Criminal Justice: Data on Noncitizen Incarcerations, Convictions, Removals, and Costs

What GAO Found The average number of noncitizens incarcerated by the Federal Bureau of Prisons (BOP) each year decreased 44 percent from fiscal year 2017 (approximately 36,300) through fiscal year 2024 (approximately 20,300). This includes noncitizens with lawful immigration status. During this time, noncitizens, as a proportion of all BOP-incarcerated individuals, also decreased. Immigration-related offenses accounted for more than half of the offenses for which BOP-incarcerated noncitizens were convicted; another 30 percent were drug-related. U.S. Immigration and Customs Enforcement removed approximately 84,800 (76 percent) of the 111,200 noncitizens who completed, at least one term of BOP incarceration from fiscal years 2017 through 2024, as of December 2025. Individuals Incarcerated by the Federal Bureau of Prisons by U.S. Citizenship Status, Fiscal Years 2017 – 2024 There are no reliable comprehensive data on all noncitizens incarcerated by states and localities. GAO analyzed data from the State Criminal Alien Assistance Program (SCAAP). SCAAP is a Department of Justice (DOJ) program that reimburses jurisdictions for a portion of the eligible costs attributable to incarcera...