Crime Rates, Not the Number of Crimes, Are a Better Way to Judge Immigrant Criminality

Now, in that example, assume that 100,000 immigrants with a homicide rate 20 percent below that of the resident population move to the city with one million residents. Because the immigrants are less likely to commit homicide than the longer‐​settled residents of the city, the homicide rate drops from 10 per 100,000 to 9.8 per 100,000, but there are eight more murders. The city got slightly safer because the increase in the population was greater than the increase in the number of murders.

That example above makes the impact of immigration on crime seem even more dangerous than it likely really is. According to crime data from 2022, 79 percent of murder victims knew their murderers where investigators knew the prior relationship. Almost half of those pre‐​existing relationships were familial or sexual, the other half were neighbors, friends, acquaintances, employer-employee, or a different relationship. Because families tend to be either mostly immigrants or mostly native‐born Americans, and they live in different parts of the city near other similar people and tend to have friends and acquaintances who are similar—including more likely to have the same immigration status—it’s reasonable to infer that most of those eight extra homicide victims were probably also immigrants.

That doesn’t make their crimes any less heinous, but it does tell you that the non‐immigrants in the city probably face even less danger than described in the previous paragraph.

A real‐world example may help explain why the focus on crime rates is more important than the number of crimes. From 1970 to 2023, the number of homicides in Detroit dropped from 495 to 252, a 49 percent decrease. Whereas somebody who shared Cuccinelli’s opinion would say that this is a significant improvement, the homicide rate rose from 33 per 100,000 in 1970 to 41 per 100,000 in 2023, a 24 percent increase. The murder rate increased even though the number of murders fell because Detroit’s population fell even more from over 1.5 million in 1970 to about 620,000 in 2023—a decrease of 59 percent. If you consider only murder, Detroit is a more dangerous city today than in 1970.

Focusing on crime rates rather than the number of crimes is essential to compare criminality between populations such as immigrants and native‐born Americans. Otherwise, there is no basis for arguing that one or the other is more criminally inclined, which really matters when discussing public safety. Additionally, we couldn’t judge whether crime differs between geographical regions or over time without looking at crime rates because the number of crimes generally goes up with the population in a cross‐section and over the long run (with some significant variation). It’s trivially easy to point to crimes committed by a member of any large population no matter how one defines it, but doing so doesn’t reveal much useful information.

What comparative crime rates reveal is that more intensive enforcement of immigration laws aimed at all illegal immigrants, not just those convicted of violent or property crimes, will not make Americans safer on average. The result would be higher crime rates, ceteris paribus.

An increase in the number of crimes does not mean that a society is becoming more dangerous if the population grows even more. Similarly, a decrease in the number of crimes will not signify an improvement in safety if the population falls even more. It would be a better outcome if the number of crimes falls along with the crime rate as the population increases.

Furthermore, nothing above is meant to diminish the harm, pain, and anguish felt by victims of crime no matter who the criminal is. Criminals should be punished and, if they are non‐​citizens, deported from the United States after serving time in prison. However, it’s clear that we have a long and arduous debate ahead of us over immigration and crime if people with strong opinions on one side, like Cuccinelli, think that “[c]rime rates do not matter.”

Alex Nowrasteh is vice president for economic and social policy studies at the Cato Institute. This article, originally posted to the Cato Institute website, is published courtesy of the Cato Institute.