Does immigration really increase crime? Here’s what the science says

One of the primary bad faith arguments against immigration is that it drives an increase in crime, a concern that tops many survey results regarding undocumented immigration. Given the sharp rise in migrations over the years, due to reasons such as climate change, economic instability and war, it’s clear that the issue is becoming more severe. And crime is generally a reasonable concern: No one wants to be the victim of violence or theft, nor do they want to live in fear of such things.

But despite the level of heated rhetoric around this issue — especially the xenophobic or racist messages that spew forth from across the political spectrum — there’s no hard data suggesting that immigration actually correlates with a rise in crime. In fact, immigration may even be associated with reductions in certain types of crime.

Take Chile, for example. Sure, it’s not the United States, but this South American country, with a population of nearly 20 million people, has its share of natives who aren’t keen on immigrants, listing crime as the primary reason. A 2018 nationally representative survey of Chileans asked about immigration concerns ranked bringing new diseases into the country as second to “drug trafficking and crime with immigrants.”

Like many countries, Chile has been experiencing an influx of immigrants in recent years. In 1990, immigrants made up just 1% of the country’s population, according to a report last year from the Migration Policy Institute (MPI). By 2020, 1.5 million immigrants in Chile accounted for nearly 9% of the country’s population. That year, the majority of these individuals traveled from Venezuela, Haiti and Peru.

Chileans have responded by installing electric fences, buying security dogs and passing laws that tighten immigration. One piece of legislation enacted in April 2021 “adopts the language of human rights protections but nonetheless enhances the government’s power to expel migrants and restrict their access to protections,” according to the MPI report.

Yet a recently published study in the American Economic Journal found “null effects” on crime from immigration, after pulling data from 2008 to 2017 from official databases on immigration, homicide and victimization surveys. “Our results suggest that while immigration does not increase crime in equilibrium, it does trigger crime-related concerns and behavioral reactions among the population,” the authors wrote. The research, led by Nicolas Ajzenman, an economics professor at McGill University, found that people who live in areas with more immigrants were more likely to rank crime as their biggest concern.

“Yet, we find no effect of immigration on crime. We analyze all relevant crimes included in the survey — robbery, larceny, burglary, theft, assault and vehicle theft — as well as homicides and observe no significant effect for any of the individual types of crime or for total crime,” Ajzenman and his coauthors wrote. Furthermore, it wasn’t clear if behavioral responses, such as installing alarms, did anything to actually reduce crime.

This research is in line with numerous other studies that have reached similar conclusions, including one published last year in the journal Economic Research which looked at three decades of data from 30 countries covering 1988 to 2018. The economist authors reported that “no statistical evidence exists to relate an increase in the number of immigrants to the rise of any kind of crime. If there is we found a significant negative association between immigrants and only one of the six kinds of crime studied,” which included homicide, serious assault, kidnapping, burglary, theft and car theft.

The authors reached this conclusion by looking at data from the United Nations Office on Crime and Drugs, which collects statistics related to criminal justice and world development. It covered countries including Australia, Austria, Chile, France, Japan, Mexico, South Korea, Spain and the US. None of them experienced an increase in crime over that period from immigrants. That isn’t to say that immigrants never commit crimes — only that the level of “delinquency,” as the authors put it, isn’t outside the normal rate for any group of humans.

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It also doesn’t matter if immigrants are undocumented or not. A 2020 study used comprehensive arrest data between 2012 and 2018 from the Texas Department of Public Safety, comparing the criminality of undocumented immigrants to legal immigrants and native-born US citizens. “We find that undocumented immigrants have substantially lower crime rates than native-born citizens and legal immigrants across a range of felony offenses,” the authors reported in the Proceedings of the National Academy of Sciences.

Nonetheless, the perception that immigration attracts crime persists, perhaps because it’s politically convenient, especially for the alt-right. If you want to get super technical, almost every nation on Earth is made of immigrants because humans originated in Africa and spread outward. Such a fact, of course, doesn’t erase the centuries of culture and history that have shaped collective identities. But if there’s one thing humans do that is universal, it’s our proclivity to move around.

As the climate continues to swing between extremes, making famine and war more likely, the number of refugees and migrants is expected to climb. People will need places to survive and may show up on the doorstep of privileged countries. The individuals who live there can greet these individuals with compassion and science, instead of fear.