%0 Report
        %A Harrington, Emma
%A Shaffer, Hannah
        %T Learning About Police Bias: Prosecutors and Police Before and After Body-Worn Cameras
        %D 2026
        %8 2026 Apr
        %I Institute of Labor Economics (IZA)
        %C Bonn
        %7 IZA Discussion Paper
        %N 18528
        %U https://www.iza.org/index.php/publications/dp18528
        %X 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.
        %K systemic discrimination
%K biased beliefs
%K monitoring
%K bodyworn cameras
%K prosecutorial discretion
%K racial disparities
%K criminal justice system