Photo by Minnesota Historical Society, Flickr CC

From Trump’s attempted restriction on immigration to his talk of building a wall on the country’s southern border, immigration policy has received renewed attention among both politicians and the public. A common reason for restricting immigration flows is association between immigration and crimes, which was explicitly mentioned by Trump along the campaign trail.  Social science agrees that immigration and crime are interconnected, but not in the way Trump and others claim.

Individual level data show that immigrants are actually less likely to engage in violent behavior than non-immigrants, with first generation immigrants being the least likely to commit crime as compared to second or third generation immigrants. Similarly, studies also find that areas with high proportions of immigrant residents are associated with lower levels of neighborhood violence and drug-crime when compared to similar neighborhoods with fewer immigrants. This association is best explained by the increases in social organization — culturally-based buffers like strong familial and neighborhood ties — and the associated economic gains stimulated by the influx of immigrants.  
This association between immigration and lower crime rates is stronger in areas with more opportunities for immigrant political action. Cities with higher levels of minority political representation and pro-immigrant legislation enhance the buffering effect of immigration on both homicide and robbery.  
What’s troubling is that even though immigrants and the areas they inhabit are associated with lower levels of crime, both documented and undocumented individuals are more likely to be incarcerated and receive longer prison sentences, even when controlling for race/ethnicity, crime severity, and other factors.