Numbers don’t back Sessions’ claim on Chicago ‘criminal aliens’

Attorney General Jeff Sessions is battling “sanctuary city” policies.

Attorney General Jeff Sessions is battling “sanctuary city” policies.

When Chicago filed a lawsuit Aug. 7 to block the U.S. Justice Department from withholding federal grant money for police from “sanctuary cities,” U.S. Attorney Jeff Sessions reacted swiftly and fiercely.

Chicago says its Police Department “will not question crime victims, witnesses and other law-abiding residents about their legal status.” It also will not use immigration status alone as grounds for detention, and it imposes strict limits on interaction between police officers and federal immigration agents.

The alleged link between illegal immigrants and surges in crime has been debunked repeatedly for decades in academic, government and advocacy-group studies. We started our look at Sessions’ statement by contacting the Department of Justice with a request for data to back up his claim.

DOJ referred us to, among other sources, a 2016 study by the Murder Accountability Project, a nonprofit group that tracks unsolved homicides and advocates better crime reporting. It showed Illinois had the nation’s lowest homicide clearance rate. But the report attributes that to record-keeping methods of the Illinois State Police in gathering crime data statewide.

Chicago Police Superintendent Eddie Johnson said in an NPR interview Aug. 7, “The vast majority of our issues in Chicago and our violent crime is committed by homegrown people — either individuals that were born and raised in Chicago or most certainly in this country. So our instances of undocumented people committing horrific crimes and murder in particular in Chicago is just — it’s nominal.”

A mountain of research casts doubt on Sessions’ assertion that illegal immigrants cause crime to rise and that Chicago’s official police policy on immigrants endangers residents.

“Immigrants are in fact much less likely to commit crime than natives, and the presence of large numbers of immigrants seems to lower crime rates,” said a 2015 report by the National Academy of Sciences. Crime went down even as the immigrant population increased, the report said.

But what about Sessions’ allegation that Chicago’s “official policy” protects “criminal aliens?”

CPD policy essentially prohibits officers from detaining anyone based on questions about citizenship status and sharply limits interaction with the U.S. Immigration and Customs Enforcement Agency. However, it establishes exceptions for suspects with criminal warrants, who are known gang members or convicted felons or are on trial for a felony.

A 2017 report by the National Immigration Law Center that focused specifically on counties that employed “sanctuary city” policies bolsters Chicago’s case. “Crime is statistically significantly lower in sanctuary counties compared to nonsanctuary (sic) counties,” it said. “The data support arguments made by law enforcement executives that communities are safer when law enforcement agencies do not become entangled in federal immigration enforcement efforts.”

Because its police department does not collect immigration data, the city can’t unequivocally state that its murder or gun violence rates are not attributable to immigrants. The anecdotal evidence in Chicago’s favor appears strong, but it’s still anecdotal.

Our ruling

Chicago does prohibit police officers from using citizenship information as the sole grounds for detaining people, and it sharply limits the interaction between city police and federal immigration agents. But evidence overwhelmingly suggests this is much less a matter of “protecting criminal aliens” than of fostering trust between local law enforcement and immigrant communities. Yet because Chicago does not collect immigration data in police interactions, it can’t be known conclusively how many of its murders and gun crimes are committed by illegal immigrants “who prey on their own residents.”

Chicago's sanctuary city policy does not protect undocumented people who commit crimes, despite what Sessions claims. We rate his statement False.


Chicago city officials “have adopted an official policy of protecting criminal aliens who prey on their own residents.”

— Attorney General Jeff Sessions on Monday, August 7, 2017 in a press release