RACE ON POLICING: Results of Estimation 2
Comparing the coefficients in the top two rows of the first column, the addition of white police is associated with a statistically insignificant 0.13 increase in the number of white total arrests per capita, whereas additional non-white officers are associated with a statistically significant increase of 18.5 arrests of white suspects. Our primary interest is in the difference between these two coefficients, rather than the levels themselves. Therefore, the bottom row of the table reports the p-value from a t-test of the null hypothesis that the impact of white and non-white officers is the same. This hypothesis of equality is rejected.
The pattern of coefficients in the second column, corresponding to total arrests of nonwhites, is the reverse of that in the first column. Non-white arrests are positively related to the addition of more white officers, but appear to decline with the addition of non-white officers.
The null hypothesis of equality across these two coefficients, however, is only rejected at the .10 level.
Parallel results are presented for the other arrest categories in the top two rows of columns 3-8. The regularity of the results across arrest categories is striking. For all four arrests categories, the addition of a non-white officer has a greater impact on white arrests, and every case except drug arrests, each extra white officer is associated with more non-white arrests. The difference is statistically significant at the .05 level in four of the eight cases. In addition, comparing across rows rather than columns (i.e. looking at whether adding officers of a given race increases arrests more within race or across race), in all eight instances the across-race effect is greater than the within-race effect.
The differences between same-race and cross-race policing are substantively large. Consider the following alternative allocations of police: (1) assign police randomly by race, and (2) assign police to maximize same-race policing, holding the present number and racial composition of police officers constant. Evaluated at the sample means of our data, moving from the first allocation to the second allocation would involve shifting just over one-quarter of all police from cross-race to own-race policing.18 Based on the coefficients in Table 2, this reassignment of officers would be predicted to yield a decrease in total arrests of 16.0 percent, and declines of 10.4, 17.1, and 11.5 percent in property, violent, and drug arrests respectively. These estimates are likely to be upper bounds on actual efficiency gains, both because minority officers may already be disproportionately assigned to minority neighborhoods in many cities, and because perfect racial matching could never actually be achieved.
Estimates of the other covariates in the regressions appear generally reasonable and consistent with past research. The fraction of non-white residents that are Black (as opposed to Asian or “other”) is positively correlated with non-white arrests, implying higher arrest rates of Blacks than other minorities. payday loan lenders only