Warning, Learning and Compliance: Evidence from Micro-data on Driving Behavior

In many contexts, warning systems of law enforcement are used to let uninformed individuals learn what is illegal, while sanctions are applied only after a number of repeated violations. Surprisingly no em- pirical evidence is available so far, over the learning impact of warnings. This paper is a first attempt to empirically investigate the warning’s effect on individuals’ behavior employing a unique database on a traffic law enforcement system, which constitutes an extraordinary nat- ural laboratory to test whether experience warning induces learning. Specifically, we use six-year longitudinal data on about 50000 drivers under the Italian point-record system of traffic law. Our statistical re- sults show that warned drivers become more compliant. To the extent individuals learn through their repeated behavior, a warning system makes it possible to apply sanctions only to (presumably) informed violators.