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Horrace article on streetlight locations and racial profiling published in Review of Econ and Stats

Apr 30, 2016

How Dark is Dark? Bright Lights, Big City, Racial Profiling

William C. Horrace & Shawn M. Rohlin

The Review of Economics and Statistics, April 2016

William C. Horrace

William C. Horrace


Grogger and Ridgeway (2006) use the daylight saving time shift to develop a police racial profiling test that is based on differences in driver race visibility and (hence) the race distribution of traffic stops across daylight and darkness. However, urban environments may be well lit at night, eroding the power of their test. The authors refine their test using streetlight location data in Syracuse, New York, and the results change in the direction of finding profiling of black drivers. Our preferred specification suggests that the odds of a black driver being stopped (relative to nonblack drivers) increase 15 percent in daylight compared to darkness.