Thursday, May 16, 2019 | 2 a.m.
A lot of research has shown that there is no causal connection between immigration and crime in the United States. But after one such study was reported on jointly by The Marshall Project and The Upshot last year, readers had one major complaint: Many argued it was immigrants in the country illegally who increase crime, not immigrants overall.
An analysis derived from new data is now able to help address this question, suggesting that growth in illegal immigration does not lead to higher local crime rates.
In part because it is hard to collect data on them, immigrants in the country illegally have been the subjects of few studies, including those related to crime. But the Pew Research Center recently released estimates of populations of immigrants in the country illegally sorted by metro area, which The Marshall Project has compared with local crime rates published by the FBI. For the first time, there is an opportunity for a broader analysis of how illegal immigration might have affected crime rates since 2007.
A large majority of the areas recorded decreases in both violent and property crime between 2007 and 2016, consistent with a quarter-century decline in crime across the United States. The analysis found that crime went down at similar rates regardless of whether the population of people in the country illegally rose or fell. Areas with more illegal immigration appeared to have larger drops in crime, although the difference was small and uncertain.
(Illegal immigration itself is either a civil violation or a misdemeanor, depending on whether someone overstayed a visa or crossed the border without authorization.)
Most types of crime had an almost flat trend line, indicating that changes in populations of immigrants in the country illegally had little or no effect on crime in the various metro areas under survey. Murder was the only type of crime that appeared to show a rise, but again the difference was small and uncertain (effectively zero).
For immigrants in the country illegally, being arrested for any reason would mean facing eventual deportation — and for some a return to whatever danger or deprivation they had sought to escape at home.
There is no exact count of immigrants in the country illegally. To create estimates, experts at Pew subtracted Department of Homeland Security counts of immigrants with legal status from the number of foreign-born people counted by the Census Bureau. Many organizations and agencies, including the DHS, use this residual estimation method. It is generally considered the best one available. As of 2016, there were an estimated 10.7 million immigrants in the country illegally, down a million and a half since 2007.
Jeffrey Passel, a Pew senior demographer, and his team estimated changes in populations of people in the country illegally for roughly 180 metropolitan areas between 2007 and 2016. For comparison, The Marshall Project calculated corresponding three-year averages of violent and property crime rates from the Uniform Crime Reporting program, and the change in those rates.
The results of the analysis resemble those of other studies on the relationship between illegal immigration and crime. Last year, a report by the Cato Institute, a libertarian think tank, found that immigrants in the country illegally in Texas committed fewer crimes than their native-born counterparts. A state-level analysis in Criminology, an academic journal, found that illegal immigration did not increase violent crime and was in fact associated with slight decreases in it.Another Cato study found that immigrants in the country illegally are less likely to be incarcerated.
At the more local level, an analysis by Governing magazine reported that metropolitan areas with more residents in the country illegally had similar rates of violent crime, and significantly lower rates of property crime, than areas with smaller numbers of such residents in 2014. After controlling for multiple socioeconomic factors, the author of the analysis, Mike Maciag, found that for every 1 percentage point increase in an area's population that was in the country illegally there were 94 fewer property crimes per 100,000 residents.
More research is underway about the potential effects of illegal immigration on crime. Robert Adelman, a professor at the University at Buffalo, the State University of New York, whose group’s research The Marshall Project and The Upshot have previously documented, is leading a team to expand on the Governing analysis. Early results suggest illegal immigration has no effect on violent crime and is associated with lower property crime, the same as Maciag found.
Preliminary findings indicate that other socioeconomic factors like unemployment rates, housing instability and measures of economic hardship all predict higher rates of different types of crime, while populations of people in the country illegally do not.
Many studies have established that immigrants commit crimes at consistently lower rates than native-born Americans. But a common concern is whether immigrants put pressure on native-born populations in any number of ways — for instance, by increasing job competition — that could indirectly lead to more crime and other negative impacts.
According to Adelman and his team, however, the impact of immigrants in the country illegally is probably similar to what the research indicates about immigrants overall: They tend to bring economic and cultural benefits to their communities. They typically come to America to find work, not to commit crimes, says Yulin Yang, a member of the team.
The data suggests that when it comes to crime, the difference between someone who is called a legal immigrant and an illegal one doesn’t seem to matter.