By Travis Carter, Jedidiah Knode and Scott Wolfe  

This report presents the results from a racial/ethnic disparity analysis of Michigan State Police (MSP) traffic stops conducted in 2021. The goal of the analysis is to identify the extent of racial/ethnic disparities in MSP traffic stop behavior across MSP worksites (i.e., posts). The analyses are based on a leading empirical approach to assessing racial/ethnic disparities in traffic stop behavior—the veil-of-darkness (VOD). The analyses account for important structural differences across posts and their jurisdictions, such as the rate of violent crime and troopers per capita, as well as temporal factors that may shape traffic patterns and stop behavior (e.g., time of day, day of week) to help ensure the results are as informative as possible. Below, we briefly outline the methodology employed and summarize the main findings. When discussing the results from this report, it is important to recognize the difference between “disparity” and “discrimination.” Disparity in these traffic stop analyses refers to differences in racial/ethnic group representation based on presumed visibility of the driver. Disparity cannot identify intent, whereas discrimination inherently involves intent. Therefore, discrimination in traffic stop behavior refers to police officers intentionally stopping individuals based on their status in a racial/ethnic minority group. Discrimination can generate disparities by way of differential treatment of racial/ethnic groups, but disparities may also be the result of nondiscriminatory (e.g., environmental, situational, etc.) factors such as crime prevalence and driving pattern differences. This report and its findings can speak only to the extent of racial/ethnic disparity in MSP traffic stops. The data cannot ascertain whether racially discriminatory practices are occurring within MSP. Although disentangling disparity from bias is critical towards improving police practices, accurately identifying the existence of such disparity and its magnitude is an important precursor to this process. More information on the data collection process is provided in the body of the report. Next, we highlight the main takeaways from the analyses.   

East Lansing:  Michigan Justice Statistics Center School of Criminal Justice Michigan State University, 2022. 33p.

By Magnus Lofstrom, Brandon Martin and Steven Raphael

We analyze the disparate effects of a recent California sentencing reform on the arrest, booking, and incarceration rates experienced by California residents from different racial and ethnic groups. In November 2014 California voters passed state proposition 47 that redefined a series of felony and “wobbler” offenses (offenses that can be charged as either a felony or misdemeanor) as straight misdemeanors, causing an immediate 15 percent decline in total drug arrests, an approximate 20 percent decline in total property crime arrests, and shifts in the composition of arrests away from felonies towards misdemeanors. Using microdata on the universe of arrests in the state in conjunction with demographic data from the American Community Survey, we document a substantial narrowing in inter-racial differences in overall arrest rates and arrest rates by offense type, with very large declines in the inter-racial arrest rate gaps for felony drug offenses. Conditional on being arrested, we see declines in bookings rates for all groups, though we find a larger decrease for white arrestees. This relatively larger decline for white arrests is largely explained by difference in the distribution of arrests across recorded offenses. Despite the widening of racial gaps in the conditional booking rate, we observe substantial declines in overall booked arrests that are larger for African Americans and Hispanics relative to whites. For some offenses (felony drug offenses), inter-racial disparities in jail booking rates narrow by nearly half. Finally, we use data from the American Community Survey to analyze…..

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  change in the proportion incarcerated on any given day and how these changes vary by race and ethnicity. For these results, we present trends for the time period spanning the larger set of policy reforms that have been implemented in the state since 2011. We observe sizable declines in the overall incarceration rate for African Americans, with the largest declines observed for African American males. The one-quarter decline in total correctional populations in the state coincided with sizable narrowing in inter-racial difference in incarceration rates.  

Bonn: Institute of Labor Economics (IZA),  2019. 55p.