MafiaThe Boston Globe ran a story over the weekend about fascinating research by sociologist Diego Gambetta…

In his new book, ”Codes of the Underworld: How Criminals Communicate” (Princeton University Press), sociologist and Mafia expert Diego Gambetta explores this subculture and unearths an unspoken language among bad men. He offers insight on how mobsters, pedophiles, prisoners, and other shady characters earn one another’s trust and prove their mettle. And what he documents is both disturbing and, sometimes, hilarious.

It turns out–according to Gambetta, a native Italian and a sociology professor at the University of Oxford–that there are really practical reasons why Sicilian mobsters like to use nicknames, why pedophiles might out themselves to others online, why prison inmates fight (or don’t fight), and why mobsters from Japan to Russia might be out there, right now, reciting lines from ”The Godfather,” such as, ”Leave the gun. Take the cannoli.”

Excerpts from the Globe’s interview with Gambetta:

IDEAS: Based on your research, what would people find most surprising about how people communicate in the criminal underworld?

GAMBETTA: I would say doing things that would seem irrational to us. Like revealing bad things that you’ve done. Or hurting yourself. Or hurting innocent people. I have a chapter on self-harm, which is probably the most unexpected thing you find.

IDEAS: What are some examples of ways criminals compromise themselves to prove their toughness or trustworthiness to another criminal?

GAMBETTA: One thing you can look at is how pedophile rings on the Internet work. Some of them work by asking new members to contribute previously unknown photographs to their website. In that sense, they contribute to the website of pedophile photographs, but at the same time they’re also giving information that they themselves have done that. So they are unlikely to be undercover agents. And with respect to physical harm, the best domain in which criminals have to prove their toughness, day in and day out, is prison. You find a lot of self-harm in prison.

Read more of the interview…