On Crime, Immigration, and Crime Data

The main objective of this newsletter is to evaluate crime and policing trends while highlighting the inherent limitations of the available data (the other objectives are to be pro-dog and to make fun of the Atlanta Falcons when possible). Given that main objective, I’m not going to highlight specific statements by certain politicians or political groups regarding the amount of violent crime being committed by immigrants nationally in this post.

Rather, in this post I’m going to attempt to realistically assess what we can and cannot say from the available data about the asserted existence of an immigrant-driven crime wave.

It's a problem that our traditional crime data collection system is poorly situated to answer. NIBRS has 4 incident types dedicated to immigration violations which could, in theory, help to shed light on the issue by identifying offenses committed along with an immigration violation. But only Federal and tribal law enforcement agencies can submit data related to those offenses and neither CBP nor DHS participate in NIBRS.

In fact, only 42 of 447 Federal law enforcement agencies submitted crime data to the FBI via NIBRS in 2022 according to data from the FBI. The beauty of NIBRS is that it provides greater insight into reported incidents of crime — in theory even immigration violations — but that only works if agencies report.

Agencies can collect information on an arrestee or victim’s residency status, but the FBI makes it very clear that this refers to where a person lives rather than their immigration status. I assume we’ve all read the 2021 NIBRS manual, but on the off chance a reader hasn’t the relevant passage notes “Resident status does not refer to the immigration or national citizenship status of the individual. Instead, it identifies whether individuals are residents or nonresidents of the jurisdiction that the incident occurred. It also enables agencies having a high transient population to show their population at risk is higher than their official resident population.”

Our only hope for identifying a potential immigrant crime wave is to look for one in regular reported crime data. Doing this suggests that if there is a wave of crimes being committed by immigrants then it’s too small to be seen in the overall national trend of falling reported violent crime — especially murder.

It may not be showing up nationally but if an influx of immigrants was causing a surge in violent crime then I would logically expect it to at least show up along the US border with Mexico. Fortunately we can measure reported violent crime across the 14 counties along the Texas border with Mexico (up-to-date crime data along the New Mexico, California, and Arizona border is less reliable) thanks to the state’s excellent UCR program.

Comparing violent crime rates in Texas border counties over time to violent crime in the US and statewide in Texas shows no evidence of increasing violent crime along the US border with Mexico. The 14 counties along the Texas-Mexico border have seen a relatively steady violent crime rate below that of the rest of their state and the nation as a whole. I used data from the Texas Department of Public Safety to calculate estimated reported violent crime rates per year in Texas border counties from 2009 to 2023 as well as the statewide violent crime rate in 2023. Data on the US violent crime rate comes from the FBI though it’s not available for 2023 yet.

Two things stand out from the above graph: reported violent crime rates along the Texas border have been pretty steady for over a decade, and violent crime in these counties tends to occur at rates that are well below the statewide and national levels each year. Zooming in on violent crimes per month in Texas border county agencies using the state’s trends tool (I had to add the 80+ agencies along the border manually) shows no real change over the past 3 years.

The same assessment holds largely true looking just at murder (assuming a roughly 10 percent decline nationally in 2023). The murder rate rose in the Texas border counties in 2020 and remained largely steady over the following four years. Murder did not decline in Texas border counties in 2023 as it did in the rest of Texas and nationwide, but I would point out that the murder in these counties is pretty rare (about 30 percent below the national average) and the difference between the rate in 2023 and 2019 is 25 total murders spread across a population of more than 2.5 million people (2023 US murder rate is approximated).

Violent crime also fell in Arizona and Nevada in 2023. None of this provides concrete evidence to support any argument regarding a relationship between immigration and crime. But if increased crime isn't showing up locally, statewide, or nationally (like it did with the obvious surge in auto thefts) then there probably isn't a hidden wave.

Jeffrey Butts of John Jay College of Criminal Justice recently smartly addressed whether there is a “Migrant Crime Wave” with the New York Times. “I would interpret a ‘wave’ to mean something significant, meaningful and a departure from the norm,” he said. “So far, what we have are individual incidents of crime.”

There are — and likely always will be — extraordinarily tragic individual incidents of crime to point to as anecdotal evidence of whatever wider trend one wants to assert. But individual tragedies do not inherently constitute a crime wave, and the lack of an overarching surge in incidents shouldn't detract from the tragedy of individual examples.

Ultimately, the US crime data system is poorly set up to definitively answer the question of whether there is an immigrant-driven crime wave. That said, the overall trend of declining violent crime nationally, and seeing no localized crime surges in the places I’d expect to see one if there was such a “wave” strongly suggests that no such thing exists.