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Calling a Place a Sanctuary City Won’t Lead to More Crime

The designation, meant to help legally protect undocumented immigrants, may encourage Latino political participation.
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San Francisco.

San Francisco.

The debate over so-called sanctuary cities — municipalities that limit local police’s assistance to federal immigration officers — has been heating up this month, as sanctuary clausestook a blow across Louisiana and became a flashpoint in Pennsylvania’s senate race. Public arguments around the sanctuary designation focus on whether it raises crime. But research already suggests that it doesn’t — and it might, in fact, be a useful tool for supporting Latino political engagement.

Sanctuary laws are notoriously hard to define. Typically, they enable local law enforcement to shield their city’s residents from federal immigration officers. The designation — taken up by some counties and states as well as cities — stems from a church community movement in the 1980s to block the deportation of Central American refugees fleeing political violence. Today’s sanctuary laws vary by location. Philadelphia, for example, bars local police from alerting federal immigration officers about an undocumented prisoner’s pending release unless the person was convicted of a violent felony and federal officers have a warrant. San Francisco goes a step further, prohibiting city law enforcement from asking about an individual’s immigration status. Even at their most protective, though, none of these designations guarantee insulation from federal immigration law.

These policies have been a hot political target since last July, following the alleged murder of 32-year-old Kathryn Steinle in San Francisco by an undocumented immigrant with seven felony convictions who has been deported from the United States five times. Presumptive Republican presidential nominee Donald Trump quickly pointed to the shooting as an example of the need for tighter border control. In late March, Republican lawmakers cited Steinle’s death in a letter urging the Department of Homeland Security to cut off funds for sanctuary cities. Though the general public opinion toward immigrants has shifted from mostly negative to mostly positive in the past 20 years, there’s also a growing divide between Democrats and Republicans, according the the Pew Research Center. A Pew analysis found that more than half of non-citizens in the U.S. live in sanctuary jurisdictions.

“We tend to cycle through these claims every couple years, usually surrounding an unfortunate incident.”

The emotional fervor caused by a death like Steinle’s can distract from the large body of research — including a 2000 report by the National Criminal Justice Reference Service and a 2014 study of American immigrants across ethnic groups — indicating that immigrants commit less crime overall than native-born Americans. That trend looks especially strong in sanctuary cities. The inverse relationship between immigration and crime, where larger immigrant populations predict less crime, is stronger in sanctuary compared to non-sanctuary cities, according to a 2013 study looking specifically at homicide and robbery.

“Recently we’re hearing a lot of rhetoric suggesting that foreign-born individuals are more predisposed to crime, or that sanctuary cities will attract people more inclined to commit crime, and there hasn’t been any statistical support for that at all,” says Highline College professor Benjamin Gonzalez O’Brien, who has conducted research inspired in part by the 2013 report on immigration, homicide, and robbery.

These findings, however, don’t necessarily mean that sanctuary status itself reduces crime. Factors that make a city more likely to pass sanctuary laws in the first place — such as having more Latino residents or liberal voters — might be driving those lower rates. What seems clearer is that sanctuary laws at least don’t increase crime, according to research being prepared for peer review by Gonzalez O’Brien and colleagues. Their analyses suggest that cities with sanctuary laws show comparable crime rates as demographically similar, non-sanctuary cities — both before and after adopting sanctuary status.

Gonzalez O’Brien’s research team’s preliminary results also show higher Latino voter turnout in sanctuary cities, highlighting the possibility that sanctuary designations politically mobilize Latinos (who wield the much-analyzed “Latino vote”). In that case, sanctuary laws might make immigrants feel more welcome and thus more willing to engage with their communities, according to Gonzalez O’Brien’s co-researcher, Loren Collingwood of the University of California-Riverside, and Christopher Lyons of the University of New Mexico, who authored the 2013 report. But this finding is subject to the same caveat as applies to the relationship between sanctuary status and crime: Cities with high Latino political engagement may be more likely to pass sanctuary laws, meaning those laws result from—rather than cause—political engagement.

We have some ways to go in understanding the effects of sanctuary status on political participation. But the research has repeatedly debunked the notion that laws favorable to immigrants increase crime. “We tend to cycle through these claims every couple years, usually surrounding an unfortunate incident like the shooting in San Francisco,” Gonzalez O’Brien says. “But scholars have been refuting these claims since the 1930s with regard to immigrant and Mexican criminality.”

While the voter mobilization perspective on sanctuary cities might be new, misconceptions about those cities’ immigrant inhabitants are not.