Are Immigrants More Likely to Commit Crimes? Meager State Prison and Local Jail Data Provide Few Insights

The relatively small number of non-citizens in these facilities becomes clearer when shown as percentages. As Figure 2 shows, the population of non-citizens of the total state prison population averaged 4.4 percent from 2002-2013, peaking at 5.2 percent before dropping significantly in 2013. In local jails, non-citizens formed an average of 7.3 percent of the population size during this period, spiking at 9 percent of the total in 2008 and remaining above 7.5 percent through 2012. However, in both state and local facilities, immigrants make up much less than 10 percent of the total in this period.

As we noted our previous post, federal data shows that federal prisons hold significantly more non-citizens, at 21 percent of the total population. The high number of non-citizens that commit immigration violations?a federal offense?would almost ensure that more immigrants would enter into the federal prison system. In the case of state and local facilities, however, authorities have convicted these individuals for violating state and local criminal statutes and ordinances. Without any additional information about these violations or the rest of the inmates of these facilities, however, authorities do not know very much about the size and profile of non-citizen population in these facilities.

The absence of standardized data on the non-citizen population in state and local detention facilities is critical to the immigration debate for two reasons. As the federal report notes, state and local facilities oversee 90 percent of the total U.S. incarcerated population, making this data essential to a full understanding of the non-citizen population in the criminal justice system. Access to reliable information on the size of this population and a comprehensive breakdown of their convictions would provide a better measure of their criminal profile and improve the capacity of policymakers to accurately assess the types of crimes committed by these individuals at the state and local level.

This data gap also has implications for the debate over “sanctuary cities,” jurisdictions that limit cooperation with Immigration and Customs Enforcement (ICE). Without this data, officials cannot determine whether complying with ICE detainer requests leads sheriff’s offices to refer larger numbers of non-citizens to ICE for processing, meaning advocates or critics of sanctuary policies can over- or understate how responding to detainers impacts the size of the non-citizen jail population. Additional information about this population would help lawmakers develop better responses to addressing issues related to non-citizens committing offenses in the United States.

Despite this data’s utility to policymakers, legal conflicts between jurisdictions that limit cooperation with ICE and the federal government may hinder gathering this information. Under federal statute, law enforcement agencies that gather immigration or citizenship status information about their arrestees or prisoners cannot be prohibited from sharing this data with ICE. Some jurisdictions that restrict their cooperation with ICE have also created policies against collecting this data to reassure immigrant communities that ICE will not access this information. DOJ has interpreted the requirements for various federal law enforcement grants to include compliance with this section of law. However, jurisdictions that refuse to collect this data assert that they do not violate this provision since they do not have any information to share. Collection of non-citizen data in jails would have to navigate these tensions between different levels of local law enforcement and federal authorities on enforcing the nation’s immigration laws, making it unlikely in the near term for any change in the status quo.