The two researchers whose work is cited over and over again for the proposition that immigrants are less criminal than Americans are Alex Piquero, ... criminology professor at the University of Texas at Dallas, and Bianca Bersani, ...sociology professor at the University of Massachusetts, Boston.
Pew cites their studies—and everyone in the media cites Pew, leading to headlines like these:
“UT Dallas prof finds immigrant kids less likely to commit serious crimes, re-offend“—The Dallas Morning News
“UMass Boston Prof: Stereotype of ‘Criminal Immigrant’ Doesn’t Hold Up“—Targeted News Service
“Surprise! Donald Trump is wrong about immigrants and crime“—The Washington Post
Curiously, we are never shown the actual studies, but simply told—with some heat—”studies show!”It shouldn't be surprising. Assuming Pinker's theory is correct, the low violent crime rates of Western Europe and those descended from Western Europeans are the result of a long, unique cultural history and social forces that are largely absent from most other cultures. Thus, lacking the inhibiting factors of Western Civilization, there is no reason for them to act, well, inhibited.
I looked up some of these alleged studies this weekend. They’re all hidden behind ridiculous Internet paywalls. I was often only the sixth person to read them.
It turns out that neither Piquero nor Bersani compared immigrant crime to “the overall population”—as the British Guardian recently claimed in an article purporting to prove Donald Trump wrong. Rather, they compare immigrants’ crime rate to the crime rate of America’s most criminally inclined subgroups.
Thus, for example, once you get past the paywall, you will find that Piquero and Bersani’s joint study, “Comparing Patterns and Predictors of Immigrant Offending Among a Sample of Adjudicated Youth,” used as its base group “adolescents who were found guilty of a serious offense.”
THAT’S NOT A REPRESENTATIVE SAMPLE OF AMERICANS! It’s a representative sample of teenagers who are convicted criminals.
Similarly, professor Bersani’s oft-cited, but never-read study, “An Examination of First and Second Generation Immigrant Offending Trajectories,” looked at a population group that included “an over-sample of Hispanic and African-American youth.”