We study the use of popular rationales to justify public anti-minority actions. Rationales to oppose minorities change some people’s private opinions, leading them to take anti-minority actions even if they are not prejudiced against minorities. When these rationales become widespread, prejudiced people can pool with unprejudiced people who are persuaded, decreasing the stigma associated with anti-minority expression and enabling greater public opposition to minority groups. We examine this mechanism through several large-scale experiments in the context of anti-immigrant behavior in the United States. In a first experiment, subjects learn that a previous respondent authorized a donation to an anti-immigrant organization and then make an inference about the respondent’s underlying motivations. Subjects informed that their matched respondent learned about a study claiming that immigrants increase crime rates before authorizing the donation see the respondent as less intolerant and more easily persuadable. In a second experiment, subjects learn about that same study and then choose whether to authorize a publicly observable donation to the anti-immigrant organization. Subjects who are informed that their exposure to the rationale will be publicly observable are substantially more likely to make the donation than subjects who are informed that their exposure will remain private. Our findings suggest that prominent public figures can lower the social cost of intolerant expression by popularizing rationales, contributing to waves of anti-minority behavior.