IDENTIFYING CHANGES IN THE SPATIAL DISTRIBUTION OF CRIME: EVIDENCE FROM A REFEREE EXPERIMENT IN THE NATIONAL FOOTBALL LEAGUE

Between the 2009–2010 and 2010–2011 seasons, the National Football League (NFL) repositioned one of its officials in order to prevent injuries among officials. This creates a quasi‐experiment for studying how a change in the extent of policing affects detection of offenses. Using play‐by‐play data from the 2009–2010 and 2010–2011 NFL season, I estimate how the detection of offensive holding changes when the positioning of an official changes. I find that there is approximately a 20 increase in the number of offensive holding penalties called after the NFL repositioned the official. Penalties called on defensive linemen fell as a result of the repositioning. Overall, there was no change in the total number of penalties called. Using the estimated change in the probability of a penalty, I estimate the probability of an official calling a penalty. I infer that NFL officials detect approximately 60% of crimes committed on the field. (JEL K4, Z0, D0 )