“Immigrants make America Great” sign held during immigration rally


BUFFALO, N.Y. — Undocumented immigration into the United States has been a hot button political topic in recent years. Now, a new study finds that undocumented immigrant populations have had little to no effect on crime rates at all. Moreover, when such groups did impact the rate of crime, a decline was noted.

Researchers at the University of Buffalo used two estimates of undocumented immigration into the United States during 2014 to come to these conclusions. The study focuses on crime across 154 different U.S. metro areas, including New York City, Chicago, and Las Vegas.

“Even after estimating the undocumented immigrant population in U.S. metropolitan areas in two different ways, we found that undocumented immigrants had no significant effect on violent crime and actually had a significant negative effect on property crime,” says Robert Adelman, an associate professor of sociology in UB’s College of Arts and Sciences, in a university release. “This suggests that increases in the undocumented population is accompanied by decreases, on average, in property crime in U.S. metropolitan areas.”

The evidence is adding up

These findings mesh well with an earlier study Adelman had conducted in 2017 focusing on the impact of legal immigration on crime rates. Just like this time around, that earlier project found no evidence more immigrants means more crime.

However, the study’s authors want to make it clear that their findings are not explicitly stating, nor implying, that individual immigrants never commit crimes.

“People from all backgrounds commit crimes. However, the bulk of the evidence indicates that, at least at the metropolitan level, in places where there are more immigrants, there also seems to be more economic and cultural vitality,” Adelman clarifies.

While this may surprise some, these findings aren’t all that groundbreaking. A number of previous projects over the past few years have come to similar conclusions. But, most of those studies focus mainly on legal immigration. This was mostly due to how difficult it is to keep track of undocumented immigrant populations.

Tracking undocumented immigrants

How did researchers overcome that hurdle this time? Instead of examining official immigrant datasets over long periods of time, they used two distinct estimates regarding undocumented immigration over the course of one year (2014). Those two estimates were put together by the Pew Research Center and the Migration Policy Institute, respectively. Despite the two estimates being quite distinct, the results of each analysis were very similar.

“Because these data [in the current study] are not longitudinal, it’s much more difficult to establish causality than when you have data that lets you look at an effect over time, but the findings are still useful because of the undocumented measures compared in the study,” Adelman explains. “There is a serious body of high quality scholarship among those who study immigration and crime whose work in general simply does not find this overwhelming negative portrait of immigrants that has been painted in the current political climate.”

“Studying the link between immigration and crime is important because it’s one of the factors that is misinterpreted in American society. The full context of immigration is complex, with competing narratives and scholarship,” he concludes. “Some groups benefit from immigration while others may realize competition from immigration, but all of this has to be placed on the table so that we can debate the issues with facts, data, and the scientific method.”

The study is published in the Journal of Crime and Justice.

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About John Anderer

Born blue in the face, John has been writing professionally for over a decade and covering the latest scientific research for StudyFinds since 2019. His work has been featured by Business Insider, Eat This Not That!, MSN, Ladders, and Yahoo!

Studies and abstracts can be confusing and awkwardly worded. He prides himself on making such content easy to read, understand, and apply to one’s everyday life.

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