Long discussion in the Washington Post of our new research on crime by illegal aliens

Jan 24, 2018 | Featured

We weren’t able to change the Washington Post fact checker’s conclusion: Trump’s claim that “illegal immigrants pouring into our country, bringing with them crime, tremendous amounts of crime” was false. But at least people got to know that there was an alternative set of numbers out there.  Besides the Washington Post, their discussion also ran in other newspapers such as the San Francisco Chronicle.  From the article:

John R. Lott of the Crime Prevention Research Center in December released a study of prisoner data from the Arizona Department of Corrections. “The murder and manslaughter rate for illegal immigrants is 2.7 times higher than the average for U.S. citizens,” Lott said of the study, which maps 32 1/2 years of prisoner statistics in a state with a history of making headlines for its tough immigration enforcement policies.

“While undocumented immigrants from 15 to 35 years of age make up a little over 2 percent of the Arizona population, they make up almost 8 percent of the prison population,” Lott found. “These immigrants also tend to commit more serious crimes.”

He added that undocumented immigrants in the Arizona data, which cover 1985 to 2017, had the highest incarceration rate compared with legal immigrants and U.S. citizens. Legal immigrants had a lower rate than U.S. citizens, he said.

“What we’re finding is that people who are legal immigrants tend to be extremely law-abiding,” Lott said. “But illegal immigrants commit crimes at extremely high rates. And when you lump them together you get something in the middle.”

The Arizona figures are “great data in the sense that it doesn’t lump the two together” and because they do not rely on offenders self-reporting their immigration status, Lott said.

Lott’s review appears to be unique — no other comparable research on state correctional data has been conducted — and an outlier, since the majority of other studies have come to diametrically opposite conclusions, including those in peer-reviewed publications. . . .

What is particularly puzzling about the Washington Post giving Trump 4 Pinocchio’s for his statement about high crime rates by Illegal aliens is that none of the other studies directly measure illegal immigrants.  All the other studies use data that either lumps legal and illegal immigrants together or they rely on illegal immigrants with criminal histories to voluntarily report that information to a stranger in a survey.  A couple of these studies try to infer who is legal or illegal with regressions, but those estimates depend on assumptions such as that none of the illegal aliens get welfare assistance such as food stamps.  How can those studies be given all the weight when there is only one study that has direct data on whether someone is an illegal immigrant and direct verifiable information on the person’s criminal history.  Let me phrase it this way: what do a lot of studies using data that lumps legal and illegal immigrants together or requires people be honest about their citizenship status and criminal history tell us about the behavior of illegal immigrants when the one study that has data on both groups shows that they are dramatically different groups?

By the way, since the piece notes regarding our study that “prisoner statistics in a state [Arizona] with a history of making headlines for its tough immigration enforcement policies,” we should mention that our research directly addresses this as a possible explanation for our results (bottom of page 10 and top of page 11) and finds no support for it.