Interior Immigration Enforcement Prior to 2014: Programs Targeting Criminal Aliens [Updated August 27, 2013] [open pdf - 2MB]
From the Summary: "Congress has a long-standing interest in seeing that immigration enforcement agencies identify and deport criminal aliens. The expeditious removal of such aliens has been a statutory priority since 1986, and the Department of Homeland Security (DHS) and its predecessor agency have operated programs targeting criminal aliens since 1988. These programs have grown substantially since FY2005, and deportations of criminal aliens--along with other unauthorized immigrants--have grown proportionally. Despite the interest in criminal aliens, inconsistencies in data quality, data collection, and definitions make it impossible to precisely enumerate the criminal alien population, defined in this report as all noncitizens ever convicted of a crime. The Congressional Research Service (CRS) estimates the number of noncitizens incarcerated in federal and state prisons and local jails--a subset of all criminal aliens--at 183,830 in 2011 (the most recent year for which complete data are available), with state prisons and local jails each accounting for somewhat more incarcerations than federal prisons. The overall proportion of noncitizens in prisons and jails corresponds closely to the proportion of noncitizens in the total U.S. population."
CRS Report for Congress, R42057
Congressional Research Service: https://crsreports.congress.gov/