Crime committed by illegal immigrants is an important public policy issue.¹ The prevalence and types of crimes committed by illegal immigrants should guide the allocation of immigration enforcement resources—at the federal, state, and local levels—with the goal of removing those who are convicted of violent or property offenses.² However, estimating illegal immigrant criminality is difficult due to various data constraints that have only recently been relaxed in Texas. This policy analysis is an update, improvement, and expansion of earlier Cato research that measured criminal conviction and arrest rates by immigration status in Texas.³ The data below are for all criminal convictions over a longer period, with a focus on homicide because it is the most serious crime and the one where the number of illegal immigrant offenders is least likely to be undercounted. Specifically, this policy analysis adjusts its methodology to account for criticisms of the quality of Texas crime data.

Most research finds that all immigrants in the United States are less likely to commit crime or be incarcerated than native-born Americans and that they don’t increase crime in local areas, with the exception of Miami immediately after the Mariel Boatlift of 1980.⁴ There is less research on illegal immigrant criminality in the United States, but it generally shows that illegal immigrants have lower incarceration rates nationwide relative to native-born Americans, lower conviction and arrest rates in Texas in earlier years, and the same rates of re-arrest.⁵ New research inspired by the Cato Institute’s earlier findings on illegal immigrant crime in Texas but based on more granular crime data found that illegal immigrants have a lower criminal conviction rate than native-born Americans and legal immigrants in that state.⁶ Recent peer-reviewed empirical studies on illegal immigrant criminality have found no link between violent crime and the size of the illegal immigration population. They also found a negative relationship between the number of illegal immigrants and most types of nonviolent crime at the local level.⁷

Researchers at the Center for Immigration Studies (CIS) interpreted Texas crime data differently, concluding that illegal immigrants have higher criminal conviction rates than native-born Americans.⁸ CIS claims that for two main reasons, much of Cato’s research undercounts the number of illegal immigrants convicted of crimes. First, CIS claims that Cato’s research did not include illegal immigrants who were later identified in prison after they were incarcerated, and thus included only illegal immigrants arrested and convicted, as recorded by the Texas Department of Public Safety (DPS). Second, CIS claims that the Texas Department of Criminal Justice (TDCJ), which oversees Texas state prisons and jails, requires time and resources to investigate the immigration backgrounds of all incarcerated prisoners. Because of those time and resource constraints, TDCJ largely focuses on investigating the immigration statuses of the most serious criminal offenders, so researchers should focus on data from earlier years for serious crimes. This policy analysis addresses CIS’s concerns in three ways: by using more specific data from Texas DPS that does not overcount or undercount incarcerated illegal immigrant criminals; by focusing on homicide; and by analyzing data from earlier years.

This policy analysis relies on data from the Texas DPS obtained through a Public Information Act request.⁹ The Texas DPS data separately show the number of convictions and arrests of individual legal immigrants, illegal immi­grants, and native-born Americans in Texas for the 10 years of 2013–2022. DPS does not explicitly identify the number of native-born American individuals arrested or convicted of crimes, but it has a third category: “unknown or other.” The only other category of people left is native-born Americans, so the “unknown or other” category is identified herein as native-born Americans.

Texas is the only state that records criminal convictions and arrests by immigration status. Texas has this informa­tion because its law enforcement agencies cooperate with federal immigration enforcement authorities at the Department of Homeland Security (DHS), which checks the biometric information of arrestees in the state and tracks them through to their convictions.¹⁰ The Texas DPS keeps the results of these DHS checks, which they label as PEP, named after an earlier system that helped local law enforcement agencies identify illegal immigrant criminals.¹¹ After criminal convictions, the TDCJ continues to investigate the immigration statuses of offenders incarcerated for some of the most serious offenses. This results in the identification and reclassification of legal and illegal immigrants who were previously categorized as other or unknown. The DPS then retains the results of both the DPS and TDCJ immigration checks.

Guaranteeing that all convicted individuals are included without double-counting is a major challenge in analyzing Texas crime data. The DPS gave data to the CIS that double-counted some illegal immigrants convicted of crimes.¹² The reasons why this double-counting occurred are complex, but Cato scholars resolved the issue through more detailed data requests on the number of legal and illegal immigrants identified only by TDCJ checks, identified only by PEP checks, and identified only by both TDCJ and PEP checks.¹³ The clearly defined variables in Cato’s data requests removed the possibility of double-counting.

The homicide conviction rates are confidently presented here because the TDCJ most intensely investigates the immigration statuses of individuals convicted of that crime. The criminal conviction rates for all crimes are also shown here, but with less confidence, because the TDCJ does not spend nearly as many resources investigating the immigration statuses of lesser criminals. This policy analysis presents criminal conviction rates for all crimes to provide a comparison that some readers may find useful, although they should interpret the rates cautiously. An additional reason to focus on homicide is that it is not an underreported crime, or at least not as underreported as other, less serious crimes.¹⁴ Thus, homicide data are the most complete for any crime and provide the best opportunity to understand criminal behavior overall and by subpopulation.

Controlling for the size of the population is essential for comparing relative conviction and arrest rates between groups, so this paper copies the methods of government agencies that generally report the conviction and incarceration rates per 100,000 members of each subpopulation.¹⁵

Calculating the crime rates for illegal immigrants, legal immigrants, and native-born Americans in Texas requires estimating the size of each subpopulation. This presents a particular challenge for illegal immigrants because the American Community Survey (ACS) and other population surveys do not specifically ask whether respondents are illegal immigrants. Even if they did ask, it would be unwise to trust the results. Thus, this policy analysis follows widely used statistical methods to estimate the size of Texas’s legal and illegal immigrant populations over the 2013–2022 period.¹⁶ That method is a modified residual method developed by economist Christian Gunadi that makes larger adjustments for the estimated undercount of the immigrant population and relaxes earlier assumptions about employment and Medicaid access due to legal changes since Gunadi first published his methods.¹⁷ Gunadi imputed legal immigrant status and identified those remaining foreign-born residents of Texas as illegal immigrants, which is different from other residual statistical methods that identify illegal immigrants first and then count the remaining foreign-born residents as legal immigrants.¹⁸ Our estimation method counts people as legal immigrants if they meet any of the following criteria as recorded in the ACS: arrived in the US before 1982; is a US citizen; received welfare benefits such as Social Security, Supplemental Security Income, Medicaid (with some adjustment based on states extending Medicaid access to illegal immigrants), Medicare, or military insurance; served in the armed forces; resided in public housing or received rental subsidies or was the spouse of someone who resided in public housing or received rental subsidies; had occupational licenses; was born in Cuba and immigrated prior to 2017; and/​or had a spouse who was a legal immigrant or US citizen.¹⁹ The number of legal immigrants estimated using this method includes those residing in Texas on temporary nonimmigrant work visas and those who have naturalized and earned American citizenship.

Our modified residual method estimates that in Texas in 2022, there were approximately 2.1 million illegal immigrants, who comprised about 7.1 percent of the state’s resident population. In the same year, there were about 3.3 million legal immigrants, who represented 10.8 percent of the population, and 24.9 million native-born Americans, who represented 82 percent of the population. Our estimates of the illegal immigrant population are sensitive to the assumptions in our model, but they are very close to DHS estimates too. Specifically, we estimated that there were 2,018,723 illegal immigrants in Texas in 2022, and DHS estimated that there were 2,060,000—a difference of 2 percent and not enough to bias our homicide or crime rate calculations relative to others.²⁰

The number of criminals identified in the data here is not the total number of criminals residing in Texas over the 2013–2022 period but merely the number of individuals arrested and convicted of homicide and other crimes by their year of arrest. Some small number of individuals may have been arrested in Texas for crimes committed in other states, but those convicted in Texas were convicted for Texas state crimes. The DPS data analyzed in this paper are for all individuals arrested and convicted in the 2013–2022 period, regardless of the year in which the crime was committed.

Texas is an ideal state to study immigrant criminality for multiple reasons: It borders Mexico; it has the second-largest illegal immigrant population of any state; it is a politically conservative state governed by Republicans; it did not have jurisdictions in most recent years that limited its cooperation with federal immigration enforcement; it has a reputation for strictly enforcing its criminal laws; and 58 percent of all Border Patrol and Office of Field Operations encounters of illegal immigrants along the Southwest border from October 2020 to January 2024 occurred in Texas.²¹

During the 10-year span from 2013 to 2022, the homicide conviction rate in Texas was 2.2 per 100,000 illegal immigrants, 1.2 per 100,000 legal immigrants, and 3.0 per 100,000 native-born Americans (Figure 1). Illegal immigrants were 26.2 percent less likely than native-born Americans to be convicted of homicide. Legal immigrants were 61.4 percent less likely than native-born Americans to be convicted of homicide. Over those 10 years, 472 illegal immigrants, 336 legal immigrants, and 7,109 native-born Americans were convicted of homicide in Texas. The years 2020 and 2021 show a substantial decline in the number of homicide convictions.

In 2022, the homicide conviction rate was 3.1 per 100,000 for illegal immigrants, 1.8 per 100,000 for legal immigrants, and 4.9 per 100,000 for native-born Americans (Figure 2). A total of 1,336 people were convicted of homicide in Texas in 2022. Of those, 1,209 were native-born Americans, 67 were illegal immigrants, and 60 were legal immigrants. In 2022, homicide conviction rates for illegal immigrants and legal immigrants were 35.6 percent and 62.3 percent, respectively, below those of native-born Americans. Illegal immigrants made up about 7.1 percent of the Texas population in 2022 but accounted for only 5 percent of all people convicted of homicide. Legal immigrants made up 10.1 percent of the Texas population but accounted for only 4.5 percent of people convicted of homicide. Native-born Americans made up 82.5 percent of the Texas population but accounted for 90.5 percent of people convicted of homicide. Illegal and legal immigrants were statistically underrepresented in homicide convictions, and native-born Americans were statistically overrepresented.

There were 2,277 total homicides in Texas in 2022, according to provisional cause-of-death data collected by the Centers for Disease Control and Prevention’s Wide-ranging ONline Data for Epidemiologic Research (CDC WONDER).²² The FBI’s Uniform Crime Reporting (UCR) Program recorded 2,020 homicides in Texas in 2022 from a subsample of law enforcement agencies that report local homicides to the FBI.²³ Different methods of reporting homicides by CDC WONDER and the UCR explain the difference between the lower number of homicides reported by the FBI and the higher number reported by the CDC. The FBI UCR gathers its statistics through a cooperative statistical collaboration of law enforcement agencies across the country. Most law enforcement agencies report data to the UCR, including the largest agencies that serve most Americans, but not all law enforcement agencies do, and their methods, quality, and consistency of recording crime data vary. CDC WONDER gathers its data from the National Vital Statistics System, which starts with state and local reporting of deaths by types that local agencies report upward using nationally standardized codes and methods to indicate the numbers and causes of deaths. In Texas in 2022, there were 1,336 convictions for homicide, which account for about 59 percent of all homicides recorded by the CDC WONDER data in that year. However, the number of convictions in that year includes some for homicides committed in earlier years because the date of arrest or the date of sentencing is the year recorded in the Texas crime data, while the total number of homicides reported by CDC WONDER is the number of homicides that were committed in 2022.

Figure 3 shows the homicide arrest rates for each subpopulation in the 2013–2022 period. In total, 729 illegal immigrants, 765 legal immigrants, and 14,710 native-born Americans were arrested for homicide in Texas. The homicide arrest rates over the entire period are 3.4 for every 100,000 illegal immigrants, 2.6 for legal immigrants, and 6.2 for native-born Americans. Illegal immigrants were 44.8 percent less likely than native-born Americans to be arrested for homicide. Legal immigrants were 57.6 percent less likely than native-born Americans to be convicted of homicide. The homicide-conviction-to-arrest ratio for illegal immigrants is 0.65 during the 10-year period analyzed here, meaning that about 65 percent of homicide arrests of illegal immigrants led to a conviction. The conviction-to-arrest ratios for legal immigrants and native-born Americans are 0.44 and 0.48, respectively, meaning that fewer arrests of legal immigrants and native-born Americans led to homicide convictions.

There are several potential explanations for the different conviction-to-arrest ratios. Law enforcement or prosecutors may be more focused on solving homicides where illegal immigrants are suspected; illegal immigrants may have less competent criminal defense on average; witnesses may be more likely to cooperate when the accused criminal is an illegal immigrant; or other factors separately or in combination could explain the difference. Regardless of the reasons, the higher conviction-to-arrest ratio for illegal immigrants could be interpreted in several different ways. For instance, illegal immigrants could be less likely to flee after committing a homicide, which would be odd because, with fewer ties to the United States than legal immigrants and native-born Americans, illegal immigrants could return to their home countries at a lower cost. Another possibility is that many do flee, and those who remain and are arrested are more likely to be convicted, which means that either those less likely to be convicted are more likely to flee or that many of the unsolved homicides in Texas were committed by illegal immigrants. Since state-level homicide clearance rates are not related to the size of the illegal immigrant population, it’s unlikely that illegal immigrants are committing a disproportionate share of homicides and escaping convictions.²⁴ Regardless, those explanations cannot be definitively ruled out without more data.

The data on all criminal convictions and arrests in Texas are more suspect than the data for homicide because, as stated above, the TDCJ does not expend many resources investigating the immigration statuses of those convicted of relatively minor crimes. Thus, readers should skeptically interpret data on the criminal conviction and arrest rates for all crimes. Regardless, the data on all criminal conviction and arrest rates by immigration status are reported here to provide a point of comparison. During the 10-year period of 2013–2022, 145,254 illegal immigrants, 159,138 legal immigrants, and 3,113,693 native-born Americans were convicted of crimes in Texas. The criminal conviction rate over the entire period is 685 per 100,000 illegal immigrants, 551 per 100,000 legal immigrants, and 1,321 per 100,000 native-born Americans (Figure 4). Illegal immigrants were 48 percent less likely than native-born Americans to be convicted of a crime, and legal immigrants were 58 percent less likely. The results are similar for arrest rates, where illegal immigrants had an arrest rate 44 percent lower than native-born Americans, and legal immigrants had an arrest rate 53 percent lower (Figure 5).

The COVID-19 pandemic and the government’s response to it peaked in 2020 and 2021. One of the myriad government responses to the pandemic was a substantial decline in homicide conviction rates (Figure 1), all criminal conviction rates (Figure 4), and all criminal arrest rates (Figure 5) in 2020 and 2021. From 2013 to 2019, the seven years preceding the pandemic, about 785 people were convicted of homicide each year in Texas. There was a clear upward trend in the number of homicide convictions in Texas during those seven pre-pandemic years, peaking at 902 in 2019. In 2020, there were only 365 homicide convictions in Texas—a 60 percent drop from 2019. The number of homicide convictions rose to 722 in 2021 but was still 20 percent below the 2019 number. The Texas criminal justice system recovered in 2022 and quickly began to make up for lost time by convicting 1,336 people for homicide—the highest number in the sample and just below the combined number of convictions in 2013 and 2014. Many of those 1,336 convictions were of individuals who would have otherwise been tried and convicted in 2020 and 2021.

The decline in convictions in 2020 and 2021 is a direct result of the Texas state government’s response to the COVID-19 pandemic. In mid-March 2020, Governor Greg Abbott declared a state of disaster in Texas.²⁵ On March 13, 2020, the Supreme Court of Texas issued the first in a series of emergency orders to address court operations.²⁶ These orders allowed courts to modify or suspend legal deadlines and procedures, suspend or limit in-person jury proceedings, authorize remote appearances, and take numerous other measures to reduce health risk.²⁷ Although the intent of the numerous orders was to protect the health of court staff, parties, attorneys, jurors, and the public, another consequence was to slow criminal prosecution and hence convictions in Texas.

A previous section details the homicide conviction rate in 2022 because it is the most recent year for which the data are reliable, but the “catch-up” convictions in that year also make it quite unusual. We should expect that high number of criminal convictions to drop somewhat in 2023 and return to the long-term trend in 2024 when the data for those years are reported. Still, during the slowdown in criminal court proceedings in 2020 and 2021, the ratios of illegal immigrant to native-born American and legal immigrant to native-born American criminal conviction rates remained similar to those of earlier years. Thus, there’s no evidence that the slowdown in homicide convictions in 2020 biased the results.

This policy analysis finds that legal and illegal immigrants were less likely to be arrested and convicted of homicide and other crimes in Texas during the 2013–2022 period. However less likely illegal and legal immigrants are to be convicted of homicide and other crimes, though, some of them are criminals. Illegal immigrants and noncitizen legal immigrants who are convicted of violent or property offenses should continue to be punished with incarceration, as native-born Americans are, and then removed from the United States. It is also clear that a broad-based interior immigration enforcement operation will not reduce American crime rates, because illegal immigrants are less crime-prone than native-born Americans (if the results from Texas are representative). Although that is not an argument against removing illegal immigrant criminals, it is an argument against removing illegal immigrants who have not been convicted of violent or property offenses in the hope that doing so would reduce crime rates.²⁸

A limitation of this research is that it is confined entirely to Texas, but illegal immigrants live in every state in the union. It’s not unreasonable to infer that, based on Texas data, illegal and legal immigrants in most other states typically have a lower homicide and criminal conviction rate than native-born Americans, because Texas is such a great sample, but the public, policymakers, and residents of other states should be certain. There very well could be states where illegal immigrants have a higher homicide or criminal conviction rate than native-born Americans; Americans should know whether that is true and, if so, where. The state of Texas should invite representatives from other states’ departments of public safety, criminal justice, and corrections to Austin to show them how to record, maintain, and track the immigration statuses of those arrested, convicted, and incarcerated for crimes. At the same time, or prior to that convening, Texas DPS should invite members of the National Research Council who work on crime and immigration, along with statisticians, social scientists, criminologists, and others with expertise in crime data, to closely examine how Texas DPS records and organizes its data to see whether its methods can be improved to ensure clarity, maximize accuracy, and minimize errors.²⁹ If an invitation from the Texas state government is not forthcoming, other states should take the initiative and ask Texas for guidance.

Texas is the only state that keeps records of the immigration statuses of those arrested and convicted of state-level crimes. Policymakers can learn much by analyzing the state-level-crime data from Texas and inferring average rates of illegal and legal immigrant criminality in the rest of the United States, both nationwide and by state. Although immigrants do occasionally commit heinous crimes, they are less likely to do so than native-born Americans. This is no comfort to the victims and their loved ones, but it is information that policymakers can use to craft better immigration and anti-crime policies. Illegal immigrants and lawfully present noncitizens who commit violent or property crimes should be removed from the United States after being convicted and punished. All states should learn from Texas and adopt its method of recording the immigration statuses of those convicted and arrested. In Texas, illegal immigrants and legal immigrants are much less likely than native-born Americans to be convicted or arrested for homicide and other crimes.

Nowrasteh, Alex. “Illegal Immigrant Murderers in Texas, 2013–2022: Illegal Immigrant and Legal Immigrant Conviction and Arrest Rates for Homicide and Other Crimes,” Policy Analysis no. 977, Cato Institute, Washington, DC, June 26, 2024.