ObjectivesThere 
is little scholarship about what affects calls for service, even as they originate the vast majority of police interventions in the USA. We test how racial perceptions, ambiguous situational contexts, and participant demographics affect desire to call the police.MethodsWe conduct a nationwide survey experiment with 2,038 participants, varying vignette racial composition (subjects described as black or white) and seriousness of event (less serious, more ambiguous or more serious, less ambiguous) to test two outcomes: 1) desire to call the police and 2) perceived threat.ResultsPerceived race does not directly affect mean desire to call the police or perceived threat. However, political views moderate the effects of race: compared to politically moderate participants, very liberal participants express less desire to call the police while very conservative participants express more desire to call the police in a vignette featuring young Black men.ConclusionsThe political polarization of desire to call the police raises questions about racially differentiated risk of more serious criminal justice system events, including arrest and incarceration, for racial and ethnic minorities.