Public officials, commentators, activists, and former police commissioners have proposed that police departments should reflect the racial demographics of the communities they serve. This argument is based on the “external legitimacy” doctrine, under which employers may give special consideration to job applicants of the same race as the clients that the employer serves. It is predicated in the belief that employees of the same race will be able to generate trust and cooperation between the employer and its clients and thus boost the external legitimacy of the employer. The external legitimacy doctrine is intuitively appealing, but also unconstitutional and counterproductive. The external legitimacy doctrine, as practiced in policing and other contexts, is itself part of what is called “racial mirroring,” which attempts to ensure that the racial composition of one defined group reflects that of another group. This piece will suggest that racial mirroring violates the Equal Protection Clause, perpetuates harmful racial stereotypes, and produces significant legal and social costs.