Many respondents to opinion surveys say that the citizen's race influences how police officers treat the public, yet recent expert social-science panels have declared that research findings are too contradictory to form a conclusion on whether American police are biased against racial minorities. We perform a meta-analysis of quantitative research that estimates the effect of race on the police decision to arrest. Screening nearly 4,500 potential sources, we analyze the results based on 27 independent data sets that generated 40 research reports (both published and unpublished) that permitted an estimate of the effect size of the suspect's race on the probability of arrest. The meta-analysis shows with strong consistency that minority suspects are more likely to be arrested than White suspects. Depending on the method of estimation, the effect size of race varied between 1.32 and 1.52. Converting the race effect size to probabilities shows that compared with the average probability in these studies of a White being arrested (.20), the average probability for a non-White was calculated at .26. The significant race effect persists when taking into account the studies’ variations in research methods and the nature of explanatory models used in the studies. Implications for future research are presented.