Frisky business: race, gender and police activity during traffic stops


Since the United States Supreme Court laid the foundation for “stop-and-frisk” activity by police departments, a substantial amount of research has explored the behavior of police departments, particularly with respect to race. But previous work rarely focuses on the individual’s probability of receiving a frisk. By exploiting a traffic stop-level dataset from the Pittsburgh Police Department, the marginal effects of assorted driver characteristics are estimated. While the broad characterization of African-American drivers being more likely to receive a frisk remains accurate, several related factors are identified that create a more nuanced picture of a driver’s probability of being frisked. The interaction of the gender of the driver, the time of day of the traffic stop, and the existence of passengers in the stopped vehicle with the race of the driver all impact the probability of receiving a frisk.

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  1. 1.

    For a related discussion in this analysis pertaining to successful versus unsuccessful frisks, please see Sect. 4.3.

  2. 2.

    Note that the rate at which white drivers are frisked is mildly higher even though fewer white drivers were pulled over; see subsequent paragraph for additional race-specific discussion.

  3. 3.

    Indeed, there exists no racial subset of males in any year that receives a lower rate of frisking during a traffic stop than any racial subset of females in any year.

  4. 4.

    Models run solely on 2012 and 2013 data utilizing five race variables produce equivalent results.

  5. 5.

    The author thanks an anonymous referee for this useful suggestion.

  6. 6.

    Note that “Controlled conditions” in Tables 5 and 6 do not constitute the total number of additional variables added to the model but the number of conditions considered—i.e., year fixed effects over three years are three conditions.

  7. 7.

    Another possibility for a greater rate of unsuccessful frisks among African-American drivers is a rational response by African-American drivers to carry fewer items of interest knowing that they have a higher probability of receiving a frisk.


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Correspondence to Matt E. Ryan.

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Ryan, M.E. Frisky business: race, gender and police activity during traffic stops. Eur J Law Econ 41, 65–83 (2016).

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  • Frisking
  • Race
  • Traffic stops
  • Gender

JEL Classification

  • K00
  • K42