SCAAP Data Suggest Illegal Aliens Commit Crime at a Much Higher Rate Than Citizens and Lawful Immigrants

Article author: 
Matt O'Brien, Spencer Raley and Casey Ryan
Article date: 
Wednesday, February 6, 2019
Article category: 
Article Body: 


This report examines the rate at which illegal aliens are incarcerated in state and local correctional facilities after being convicted of a crime. To determine that rate:

  • We analyzed incarceration data from the federal government’s State Criminal Alien Assistance Program (SCAAP) and compared it to the public records of state and local prisons.[5]
  • Via SCAAP, state entities apply to U.S. Immigration and Customs Enforcement (ICE) to obtain reimbursement for the costs associated with incarcerating illegal aliens.
  • Accordingly, the rate at which a state seeks reimbursement provides a good snapshot of the number of illegal aliens in its criminal justice system.
  • In order to estimate how many illegal aliens are currently incarcerated in a given state, we relied on data from the most recent SCAAP report published by the Department of Justice’s (DOJ) Bureau of Justice Assistance (BJA).[6]
  • Our other calculations are based on commonly available state corrections/criminal justice reports and other non-SCAPP federal data.


SCAAP data indicate that illegal aliens are typically at least three times as likely to be incarcerated than citizens and lawfully-present aliens.


Other critics assert that any claims that illegal aliens commit crimes at a higher rate than lawfully-present immigrants or U.S. citizens are motivated solely by racism inherent in American law enforcement. However, data on conviction rates and plea bargains generally indicate that the correlation between arrest and subsequent conviction in the United States is high. Conviction rates in state jurisdictions vary but are typically over 50 percent. For example, 84 percent in Texas, 82 percent in California and 67 percent in New York.[23] Accordingly, courts appear to be regularly finding that police and prosecutors have sustained their burden in proving that charged illegal aliens have actually committed the crimes of which they are accused. There does not appear to be any indication that illegal alien incarceration rates are being artificially inflated by overly aggressive enforcement activity.