More Immigrants Less Crime?

That's the theme of an article in the NYTimes magazine last weekend:

The most prominent advocate of the “more immigrants, less crime” theory is Robert J. Sampson, chairman of the sociology department at Harvard. A year ago, Sampson was an author of an article in The American Journal of Public Health that reported the findings of a detailed study of crime in Chicago. Based on information gathered on the perpetrators of more than 3,000 violent acts committed between 1995 and 2002, supplemented by police records and community surveys, it found that the rate of violence among Mexican-Americans was significantly lower than among both non-Hispanic whites and blacks.

If I follow the argument, immigrants, at least some groups of immigrants, bring social capital, incentives, and relationships to the U.S. that makes them less likely to commit crime. That is, legal immigrants have their families and a strong family culture; illegal immigrants want to keep out of sight of the police because the consequence is going back home. (So much for locking them up.) The bad side of the argument is that as their kids grow up American, they commit more crime. It's interesting, though I'm not totally convinced.