Precinct or prejudice? Understanding racial disparities in New York city’s stop-and-frisk policy

Sharad Goel, Justin M. Rao, Ravi Shroff

Research output: Contribution to journalArticle

Abstract

Recent studies have examined racial disparities in stop-and-frisk, a widely employed but controversial policing tactic. The statistical evidence, however, has been limited and contradictory. We investigate by analyzing three million stops in New York City over five years, focusing on cases where officers suspected the stopped individual of criminal possession of a weapon (CPW). For each CPW stop, we estimate the ex ante probability that the detained suspect has a weapon. We find that in more than 40% of cases, the likelihood of finding a weapon (typically a knife) was less than 1%, raising concerns that the legal requirement of “reasonable suspicion” was often not met. We further find that blacks and Hispanics were disproportionately stopped in these low hit rate contexts, a phenomenon that we trace to two factors: (1) lower thresholds for stopping individuals—regardless of race—in high-crime, predominately minority areas, particularly public housing; and (2) lower thresholds for stopping minorities relative to similarly situated whites. Finally, we demonstrate that by conducting only the 6% of stops that are statistically most likely to result in weapons seizure, one can both recover the majority of weapons and mitigate racial disparities in who is stopped. We show that this statistically informed stopping strategy can be approximated by simple, easily implemented heuristics with little loss in efficiency.

Original languageEnglish (US)
Pages (from-to)365-394
Number of pages30
JournalAnnals of Applied Statistics
Volume10
Issue number1
DOIs
StatePublished - Mar 1 2016

Fingerprint

Crime
Hits
Likelihood
Likely
Trace
Heuristics
Requirements
Estimate
Demonstrate
Policy
Prejudice
Racial disparities
Minorities
Context
Strategy
Evidence
Public housing
Factors
Tactics
Suspicion

Keywords

  • Criminology
  • Discrimination
  • Fourth amendment
  • Racial profiling
  • Risk assessment

ASJC Scopus subject areas

  • Statistics and Probability
  • Modeling and Simulation
  • Statistics, Probability and Uncertainty

Cite this

Precinct or prejudice? Understanding racial disparities in New York city’s stop-and-frisk policy. / Goel, Sharad; Rao, Justin M.; Shroff, Ravi.

In: Annals of Applied Statistics, Vol. 10, No. 1, 01.03.2016, p. 365-394.

Research output: Contribution to journalArticle

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