SEATTLE—In September 2017, California made itself a “sanctuary state,” and critics predicted dire consequences. It adopted a law, SB54, that bars state and local governments from enforcing federal immigration laws. Passed as a counter to the Trump administration’s aggressive crackdown on immigration, the bill prevents police from asking citizens about their immigration status and limits their ability to help federal immigration authorities.
Critics of SB54 argued that the bill would handcuff local law enforcement and ultimately lead to an uptick in violent crime. Reduced threat of deportation, they reasoned, would embolden illegal immigrants to commit more crimes and report more crimes. But a new study presented here today at the annual meeting of AAAS, which publishes Science, does not bear out those fears. Instead, it reveals no uptick in violent crimes or property crimes since SB54 was enacted.
Research had already shown that immigrants are less likely to commit crimes than native-born citizens, and that crime rates did not change significantly in cities that adopted similar sanctuary laws. But Charis Kubrin, a criminologist at the University of California (UC), Irvine, set out to survey the impact across the entire state. The results, which Kubrin says are “the first of their kind,” have been peer-reviewed, but are not yet published.
“I think this is a very interesting and important paper,” says Alex Piquero, a criminologist at the University of Texas, Dallas, who was not involved in the research. He is the editor of Justice Evaluation Journal, where the study is in press.
The ideal way to test the impact of SB54 would be to divide California into two equal test groups and then enact the legislation in one and not the other. Since this is impossible, Kubrin and her UC Irvine co-author Bradley Bartos compared California with a “synthetic version” of itself lacking SB54.
The team scoured the rest of the United States for areas that matched California in rates of violent (homicide, robbery, aggravated assault) and property (burglary, larceny, auto-theft) crimes between 1970 and 2017. They could then compare how crime rates evolved after 2017 in the “two states” to see whether SB54 was having any influence.
After SB54 was introduced, the crime rate in California continued to closely mirror the rate in synthetic California, the team found. “Sb 54’s impact on violent crime was null,” Kubrin says.
The study has several limitations. For one, little time has passed since SB54 took effect, and any effect may not have emerged yet. And because the study treats the state of California as a homogenous entity, it may not capture increases in crime rate at local levels if they are balanced by reductions elsewhere.
Kubrin is planning more granular studies that focus specifically on regions with large numbers of immigrants. Piquero says these studies should be done before the findings are used to inform policy. “I think that there needs to be a bit more follow-up,” he says, “and perhaps some deep-dive into a few of the cities in CA that may be dealing with the issues within SB54 more directly.”