Critical mass condition of majority bureaucratic behavioral change in representative bureaucracy: a theoretical clarification and a nonparametric exploration.

This article investigates the concept of "critical mass" within representative bureaucracy theory, focusing on how increased minority representation in bureaucratic organizations influences majority members' behavior, specifically White police officers’ conduct toward minority drivers. Using individual-level traffic stop data from Washington and South Carolina, the study employs a semiparametric, nonparametric regression approach to identify thresholds of Black officer representation—6–9% in Washington and 9–11% and 19–23% in South Carolina—at which White officers demonstrate improved search accuracy and reduced bias toward Black drivers. While increased Black representation correlates with more equitable policing outcomes, full parity between Black and White drivers is not achieved, and no significant critical mass effects are found for Hispanic representation in either state. The study highlights the importance of clarifying underlying behavioral mechanisms and suggests that both the quantity and quality of intergroup contact may affect the critical mass needed for behavioral change, offering methodological and theoretical contributions to the study of diversity and administrative behavior in public organizations.