Mobsters involved in higher-level crimes such as drug-dealing or loan-sharking saw the greatest return on their education. As co-author Giovanni Mastrobuoni explained to Fortune, going to college likely proved a boon to their business sense, helping them with skills like “dealing with numbers, organizing your thoughts, organizing a group, and so on.” That’s probably also why mafia members involved in simple violent crime didn’t see quite as high a return on their college degrees.

Not only is the paper the first academic attempt to study education’s effects on criminal activity, it also shows that college degrees prove useful nearly everywhere—even outside the law. “Behind every successful fortune, there is crime” was another choice Puzo quote.

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