When dubious pro-gun researcher John Lott issued a study claiming that undocumented immigrants commit more crime than U.S. citizens — a finding described as an outlier, since most other studies on the issue have found the opposite — The Media Research Center jumped right on it.
The Media Research Center’s Brad Wilmouth highlighted that “liberal CNN contributor Van Jones insisted that illegal immigrants are less likely to commit crimes than the general population as right-leaning CNN contributor Rick Santorum cited a recent study by John Lott finding that illegal immigrants in Arizona commit crimes at twice the rate of the general population.
At the MRC’s “news” division, CNSNews.com, Craig Bannister touted the study:
Undocumented (illegal) aliens are far more likely to commit crimes, as well as to commit serious crimes, than are U.S. citizens, a new study of 33 years of Arizona prison data reveals.
The study, “Undocumented Immigrants, U.S. Citizens, and Convicted Criminals in Arizona,” by Crime Prevention Research Center President John R. Lott, also extrapolates that data to estimate how many additional crimes were committed nationally in 2016 by illegal immigrants, if Arizona is representative of the U.S. as a whole.
The study provides a uniquely accurate picture of illegal immigrant crime, its abstract notes, because it relies on comprehensive state records of every prisoner incarcerated over a 33-year period, delineated by citizenship status:
Well, it turns out the study wasn’t so “uniquely accurate” after all. Alex Nowrasteh at the Cato Institute explains how Lott botched the study:
The variable that Lott focused on is “CITIZEN.” That variable is broken down into seven categories. Lott erroneously assumed that the third category, called “non-US citizen and deportable,” only counted illegal immigrants. That is not true, non-US citizen and deportable immigrants are not all illegal immigrants. A significant proportion of non-U.S. citizens who are deported every year are legal immigrants who violate the terms of their visas in one way or the other, frequently by committing crimes. According to the American Immigration Council, about 10 percent of people deported annually are Lawful Permanent Residents or green card holders—and that doesn’t include the non-immigrants on other visas who were lawfully present in the United States and then deported. I will write more about this below.
Lott mistakenly chose a variable that combines an unknown number of legal immigrants with an unknown number of illegal immigrants. Lott correctly observed that “[l]umping together documented and undocumented immigrants (and often naturalized citizens) may mean combining very different groups of people.” Unfortunately, the variable he chose also lumped together legal immigrants and illegal immigrants.
[…]Lott’s controversial empirical findings regarding the high admission rate of illegal immigrants to Arizona prisons, a finding that contradicts virtually the entire body of research on the topic, stems from his simple misreading of a variable in the 1985-2017 ADC dataset. Lott thought that “non-U.S. citizens and deportable” describes only illegal immigrants but it does not. There is no way to identify illegal immigrants with precision in the 1985-2017 ADC dataset and their population can only be estimated through the residual statistical methods that Lott derides as “primitive.” Using another variable in the June 2017 ADC dataset that Lott did not analyze reveals that, at worst, illegal immigrants in Arizona likely have an incarceration rate lower than their percentage of that state’s population.
The MRC and CNS have so far failed to correct the record so their readers know the truth.