Immigration Prevents Crime?

Well, at least the authors aren't claiming that illegal immigration cuts crime.

Baltimore, Philadelphia and other cities in a bloodstained corridor along the East Coast are seeing a surge in killings, and one of the most provocative explanations offered by criminal-justice experts is this: not enough new immigrants.
The theory holds that waves of hardworking, ambitious immigrants reinvigorate desperately poor black and Hispanic neighborhoods and help keep crime down.

It is a theory that runs counter to the widely held notion that immigrants are a source of crime and disorder.

"New York, Los Angeles, they're seeing massive immigration - the transformation, really, of their cities from populations around the world," said Harvard sociologist Robert J. Sampson. "These are people selecting to go into a country to get ahead, so they're likely to be working hard and stay out of trouble."

Lou Dobbs has the stats.