Williams looked at data on self-reported thefts from the National Longitudinal Survey of Youth from Ohio State University, which followed more than 8,000 people between 1997 and 2011. In addition to lots of other things, the survey asks people if they stole anything in the past year and how much it cost. Williams classifies those who report stealing at least one item worth more than $50 in the last year as "thieves" and those who stole something worth less than $50 as "petty thieves."
He finds that theft isn't that uncommon -- 16 percent of the people overall, one in five men and one in 10 women, report having stolen something worth more than $50 in the last year. Including the petty thieves, the numbers rise to one in three men and one in four women. These statistics are self-reported, so they likely miss out on some people who simply don't report their theft.
The thieves include a disproportionate number of men, minorities and people with less education, as well as people who smoke, drink, have mental health challenges and lower standardized test scores.
What is striking in the research is that Williams finds that thieves are active for only very short periods of time -- on average, less than one year. Over the 15 years of data, fewer than 5 percent of thieves continue their behavior for more than three years.
The data suggests that a "thief" is less a type of person than a stage some people go through at one point in their lives -- specifically, adolescence. "For the majority of offenders, property crime may simply be an exploratory phase," Williams writes. Theft drops off very sharply as people leave their teen years, as the chart below shows.
The second major thing Williams finds is that this type of crime literally doesn't pay. The median earnings from one single act of theft are only $37.50, and a surprising amount of thieves make nothing or next to nothing per theft. The graph below, which shows the data on thefts and earnings for all the people in the survey who stole something between 1997 to 2011, shows how unprofitable the vast majority of thefts are:
Basically, there is no example of successful thieves in the data, Williams wrote. Unlike drug dealing or other types of crime, which can sustain people economically for much longer periods, being a thief appears to be a poor substitute for having a legitimate job.
There's more evidence in the study that theft doesn't have that much to do with money. For people younger than 24 -- the period of life when most thieves are active -- Williams finds little correlation between a person's propensity to steal and how much income they have. For those under 24, there's also little connection with the income of the person's family. At least in this data set, growing up poor doesn't make young people that much more likely to steal.
"If I showed you a plot of wages or employment for thieves and non-thieves, and then if you break it down into men and women, they look identical," Williams said in an interview.
These trends defy conventional logic for a couple of reasons, Williams says. First, most people believe thieves are stealing things because they don't have a faster way to riches -- if they did, they'd probably just work for their spoils, right? Second, you would think that the people who are stealing things would have lower incomes, because they might have problematic attitudes or behaviors that would cause employers to pass them over.
Many people seem to believe that there's a direct relationship between poverty and theft -- that being poor encourages you to steal things. But before the age of 24, that isn't really the case.
Over the longer run, however, there does appear to be some kind of deeper, indirect relationship between theft and poverty, Williams says. By age 30, thieves have lower incomes than non-thieves.
The study doesn't reveal why this is the case. But to Williams, the findings suggest that their may be a missing behavioral piece of the puzzle -- a third factor that is influencing both a person's propensity to be a thief and their income.
Drawing on previous research, Williams says that he suspects this might be that the people who end up as thieves have less foresight and self-control. These people may think more about instant gratification than future consequences, such as the threat of punishment, lost future earnings due to a criminal record, or the social stigma of being caught red-handed. His research also shows that drinking and smoking, two activities that researchers associate with less patience and foresight, are correlated with theft.
"We're looking at people who don't pass the marshmallow test," Williams says -- referring to a famous study at Stanford in which children were given the choice of one marshmallow now or two marshmallows several minutes later. The researchers found that the patience and self-control that this test reflected was one of the best predictors of long-term success in life.
So what about "Ocean's Eleven" or "The Pink Panther"? Is the smart, calculating, successful thief entirely a myth? The study mentions that professional thieves probably do exist, but they're so rare that they're hard to find in surveys -- probably fewer than 1 in every 100,000 people.
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