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Learning About Police Bias: Prosecutors and Police Before and After Body-Worn Cameras

Author

Listed:
  • Harrington, Emma

    (University of Virginia)

  • Shaffer, Hannah

    (Harvard Law School)

Abstract

Decision-makers often rely on earlier actors but fail to correct for their biases. We model and measure two mechanisms: underestimating upstream bias and treating subjective information as ground truth. We link an original survey of 203 North Carolina prosecutors to their 505,787 cases. Exploiting the rollout of police body-worn cameras (BWC), we show monitoring reduces incarceration disparities by 14 percent, little of which is driven by arrests. About one quarter of this effect reflects learning: prosecutors with greater BWC exposure view police as more biased and unreliable. Monitoring reduces disparities most for prosecutors who treat police reports as ground truth.

Suggested Citation

  • Harrington, Emma & Shaffer, Hannah, 2026. "Learning About Police Bias: Prosecutors and Police Before and After Body-Worn Cameras," IZA Discussion Papers 18528, IZA Network @ LISER.
    • Handle: RePEc:iza:izadps:dp18528
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    References listed on IDEAS

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    Keywords

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    JEL classification:

    • J15 - Labor and Demographic Economics - - Demographic Economics - - - Economics of Minorities, Races, Indigenous Peoples, and Immigrants; Non-labor Discrimination
    • K14 - Law and Economics - - Basic Areas of Law - - - Criminal Law
    • K42 - Law and Economics - - Legal Procedure, the Legal System, and Illegal Behavior - - - Illegal Behavior and the Enforcement of Law
    • D82 - Microeconomics - - Information, Knowledge, and Uncertainty - - - Asymmetric and Private Information; Mechanism Design
    • D83 - Microeconomics - - Information, Knowledge, and Uncertainty - - - Search; Learning; Information and Knowledge; Communication; Belief; Unawareness

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