The evidence is overwhelming that immigrants in the United States have had a lower crime rate than native-born Americans since at least the 19th century. When people learn that fact, they aren’t surprised that legal immigrants have a lower crime rate than native-born Americans, but they are surprised that it’s also true for illegal immigrants. The follow-up question people ask is, “Why do illegal immigrants have low crime rates?” It’s a good question.
After all, illegal immigrants broke immigration laws when they entered or overstayed, and they tend to be younger, male, less educated, have lower wages, and are members of ethnic or racial groups that tend to have higher crime rates among native-born Americans. Thus, it’s understandable why people are perplexed about why illegal immigrants have a lower crime rate in the United States. That’s where theories of crime come in.
Theories can help interpret or explain results, guide research design, help make predictions, and reconcile multiple findings. Listing these theories can help answer the question of why illegal immigrants and other immigrants have a lower crime rate in the United States. You should notice that many of the theories below contradict each other, and some are likely entirely false, but several could be partial explanations.
Professors Charis Kubrin and Graham Ousey have a short guide to these theories in a recent book on immigrant crime, but I will add a few more. I’m partial to theories 1–3, but there are plausible cases for others too.
Theories That Can Explain the Illegal Immigrant-Native Crime Difference
- Comparison group effect: Native-born Americans commit more crime than residents of any other developed country and several less developed countries. Illegal immigrants who come here are much less crime-prone by comparison. Even immigrants in Europe, where immigrants tend to have a higher crime rate than native-born Europeans, would have a lower crime rate than native-born Americans if they came here instead. Illegal immigrants are just law-abiding by comparison.
- Selection effects: Legal and illegal immigrants tend to think about the future, which is why they incurred a large cost to immigrate in the first place. The present value of work in the United States is greater than work in another country, so they made the investment to come here. People who tend to think about the future commit fewer crimes and have more self-control. That’s why Mexican Americans commit much less murder than Mexicans in Mexico or, generally, than other people from countries that send many immigrants and have higher crime rates. If immigrants to the United States by their region and country of birth had the exact same homicide offending rates in the United States as the countries they came from, the homicide rate in the US would be about 17 percent higher than it really is, and the number of people murdered per year would be higher by about 3,752, according to a back-of-the-envelope estimate. That’s good evidence for self-selection.
- Deterrence: The cost of committing a crime for the criminal is the probability that he will be punished multiplied by the harshness of the punishment. If the punishment is higher for illegal immigrants than for native-born Americans, they would be more deterred from committing crimes. The prior two economic theories above and deterrence combine into Gary Becker’s canonical crime model, in which people don’t commit crimes whose expected costs exceed the benefits. If the expected costs and/or probability of getting caught are higher for illegal immigrants, they’ll be less likely to commit crimes. Deterrence may be higher for immigrants for several reasons, such as greater police presence in immigrant communities because of fear of immigrant crime, or a higher fear of deportation may incentivize them to obey the laws.
- Demographics: Immigrants change age and sex structures of the areas where they settle, which can affect crime rates by increasing the share of more crime-prone populations where they settle. An increase of immigrants who tend to be younger males is likely to increase crime while a decrease in that demographic would likely decrease crime.
- Poor economic outcomes: Illegal immigrants may do poorly in local economies and have trouble finding jobs. As a result, they could commit more property crimes to increase their incomes. There’s evidence that state-level immigration enforcement laws in Arizona may have increased crime (or not) and that national immigration laws intended to enforce immigration laws increase crime rates. Additionally, prior amnesties for illegal immigrants probably diminished crime for the legalized population because they had additional economic opportunities.
- Economic revitalization: Immigrants may do well in local economies, increasing economic and job growth in areas. As a result, more locals and immigrants would have less reason to commit property crimes because they have other opportunities to earn income.
- Culture: Immigrants may be more or less tolerant of lawbreaking based on their cultures. Rapid, slow, or nonexistent assimilation may determine how much they adjust over time. Immigrants who don’t assimilate may also develop an oppositional culture that flaunts local norms and rules, leading to higher crime. This theory does not assume that immigrants fail to react to incentives, but the degree to which they would react is somewhat bounded by the culture of their origin countries.
- Legal cynicism: Police patrol immigrant neighborhoods more, which could lead to community distrust of the police and criminal justice system, which leads to less willingness to assist law enforcement, which leads to less effective deterrence and higher crime. Illegal immigrants could react poorly to police presence.
- Social disorganization: Immigration increases diversity, which causes social fragmentation and the dissolving of social bonds, norms, and other difficult-to-measure social science concepts that cut the cost of committing a crime. As a result of diminished social control through depleted social capital, more people could become criminals.
- Social bonds: Immigrants have stronger social bonds with family, local civil society, and churches than native-born Americans do. As a result of these stronger bonds, there are fewer marginalized loners who choose crime, and members of the community are there to help those who are tempted by a life of illegal behavior.
- General strain: Illegal immigrants face much strain and uncertainty. As a result, they could react by committing or not committing crimes.
- Peer influence: Illegal immigrants fear deportation, so they try to fit in and not draw attention to themselves. One way of doing that is socializing with people who also want to fit in and not draw attention to themselves. Those types of people tend to commit fewer crimes. This is a subcomponent of selection effects.
Whether immigrants have a lower crime rate than native-born Americans is ultimately an empirical question. Theories of why people choose to commit or not commit crime from sociology, criminology, and economics are a good starting point for explaining differences in crime between the two groups.