The notion of the cat burglar is one Hollywood likes to romanticize: A suave gentleman or lady with a penchant for mischief and fondness for shiny things, thrilling us as we watch them break in and steal objects of their desire. From Cary Grant in Hitchcock's To Catch a Thief, to the Californian teenagers in Sofia Coppola's The Bling Ring (based on Nancy Jo Sales's depiction of the real group of teenagers burglarizing the homes of L.A. celebrities in 2009), burglars are either portrayed as sexy thieves or slapstick comedians a la the Hamburglar.

In reality, of course, burglaries are intrusive and distressing to the victims. And though burglary rates have fallen by 25 percent internationally in the last decade, they are nevertheless common. The FBI estimates that there were nearly 2 million burglaries in 2013, with 60 percent of those crimes involving forced entry. The total losses are estimated at $4.5 billion; averaging out to around $2,300 per burglary. Clearance rates for burglaries, meaning the rate at which a crime is solved, are also notably low at 13.1 percent. In the U.K., where the clearance rate is 17 percent, burglars account for two-thirds of the convicted population.

Claire Nee, a researcher at the University of Portsmouth in the U.K., has been studying burglary and other crime for over 20 years. Nee says that the low clearance rate means that burglars often remain active, and some will even gain expertise in the crime. As with any job, practice results in skills. "By interviewing burglars over a number of years we've discovered that their thought processes become like experts in any field, that is they learn to automatically pick up cues in the environment that signify a successful burglary without even being aware of it. We call it 'dysfunctional expertise,'" explains Nee.

Dysfunctional expertise describes the ways a burglar think differently than a normal person. According to Nee, burglars are often working even as they pursue normal, non-criminal, activities. As they are going about their day, burglars are constantly making mental notes and calculations—marking properties that look vulnerable, considering the hours they'll be empty, and thinking about the potential pay-off. Over time, this process becomes unconscious and automatic.

Can security measures help keep a house safe? Not really, according to Nee. "Good security is a deterrent but householders are notoriously bad at actually using the devices they install, so this is rarely a problem for the burglar," she says. "Most burglars will return to a vulnerable neighborhood or street later when they are ready to do the burglary. So they have a lot of competence at choosing properties to burgle and are rarely caught at the scene. Most burglaries are neither impulsive nor heavily planned."

In order to further study whether this expertise of burglars was real, Nee set up an experiment with a group of researchers from University of Portsmouth and University of Sussex. Using a real house, Nee recruited six ex-burglars and six grad students to measure whether burglars were better than the students at burglary. They found that the ex-burglars were more covert and efficient—all of them entered and exited the property from the back, and they were much more systematic in the ways they used their time inside. Burglars focused on high value areas, and surprisingly, they spent more time in the house than the students. The burglars took fewer items but more valuable ones—on average, their hauls were worth 1,000 pounds (or roughly $1,500) more than that of the students.

While this study's participant size is small, it's still interesting to look at how expert decision-making works in burglaries. Nee says that it's important to understand the decision-making process of burglars in order to reduce opportunity and design better rehabilitation programs, because, for now, burglary is not a great job, but it's also one that's hard to quit.