Reference populations for examining possible racial profiling

Abstract Two recent Massachusetts Supreme Court cases, Commonwealth v. Long (2020) and Commonwealth v. Robinson-Van Rader (2023), have made it easier for defendants to successfully challenge police stops allegedly based on race or another protected class. Such challenges often consist, at least in part, of demonstrating that the racial distribution of those stopped by police differs meaningfully from the racial distribution of an appropriate reference population. We describe a series of cases, culminating in Long and Van Rader, that have clarified the legal standard required to mount a successful racial profiling challenge in Massachusetts as well as the nature of appropriate reference populations. In some of these cases, we served as expert witnesses.