Is There Racial Bias in the Enforcement of Primary Seat Belt Laws? Evidence from Veil of Darkness Tests

Abstract

Abstract State mandatory seat belt laws have become stricter over time, allowing for a vehicle to be stopped solely for a suspected seat belt infraction. While effective in reducing traffic fatalities, this additional discretion may also come with the possibility of increased racial targeting. Using individual-level traffic stop data, I combine recent advances in the Veil-of-Darkness test with a difference-in-difference identification strategy to estimate whether primary seat belt laws are associated with changes in the racial composition of seat belt stops. Results indicate that under primary seat belt enforcement, a black individual is 1.138–1.222 times more likely than a white individual to be stopped for a seat belt violation under the good visibility of daylight compared to the poor visibility of darkness. These additional stops end mostly in warnings, suggesting the law is used to increase the number of pretextual stops made, specifically on black drivers.