That’s the finding of research by a British university, which focused on the education levels of members of the Italian-American mafia between the 1930s and 1960s. It established that for each additional year of education, gangsters saw a rise in income of as much as 8.5%.

In ‘Returns to Education in Criminal Organizations: Did Going to College Help Michael Corleone?’, academics from the University of Essex used data from the United States 1940 Census of Population and information from the Federal Bureau of Narcotics to study the income, education, and job characteristics of 712 Mafiosi.

The academics compared the mobsters’ returns to education with a number of other non-mafia groups, including Italian immigrants, second-generation Italian men, and a sample of neighbors who lived in close proximity to them. It found that the mobsters’ returns were only slightly behind those of their neighbors, who pulled in as much as 10% additional income for every year of education. The mafia members actually outperformed immigrants, particularly Italian immigrants.

“Overall the mobsters did quite well,” said Giovanni Mastrobuoni, one of the authors of the report. “They had returns to education that were far higher than individuals in the census of Italian origin, as well as immigrants, and they had returns to education which were similar to the US population overall.”

Mobsters tended to leave school an average of one year earlier than their neighbors, the report found, and the impact of education varied depending on the type of criminal activity an individual was involved in. Those who carried out relatively sophisticated crimes that involved running an illegal business—such as loan sharking or bootlegging—saw returns to education that were three times higher than those involved with violent crimes like robberies or murder.

“What we found was the returns to education were much, much larger for the business type of criminals, those that we think need those abilities that you learn in school,” said Mastrobuoni. “So dealing with numbers, organizing your thoughts, organizing a group, and so on … the ‘soldiers’, the ones doing the dirty jobs, we find very, very low returns to education.”

Would it be possible to carry out a similar study of organized crime groups today? Mastrobuoni isn’t so sure. The 1940 census contained a level of detail that isn’t found in today’s versions, he says, and it would be very difficult to collect the information at source. Some researchers have carried out interviews with people in prison, according to Mastrobuoni, “but even there, you are basically selecting a group of individuals who have been caught, and they might be different from those that are never caught.”

“The issue with criminals is that they tend not to respond to surveys,” he says.