As protests erupted across the United States in recent years over politically polarized issues (e.g., Black Lives Matter, COVID-19 restrictions), so too did questions about when and how police should respond. The context of these protests and how police reacted to them varied substantially, with limited understanding of relevant public attitudes. Public opinion is double-edged; it is critical for police legitimacy and influences criminal justice policy, but it also often reflects racial animus. We hypothesized that disruptive, dangerous, or unlawful protest tactics would increase support for police control, by elevating public fear, but also that support for repression would be higher when protest goals conflict with preexisting racial beliefs. To test our hypotheses, we embedded an experiment in a nationwide survey fielded in 2020, after George Floyd’s killing sparked the broadest protests in U.S. history. We randomized protest tactics (e.g., weapon carrying, violence) and goals, as well as other contextual characteristics (e.g., protest size). We found that the public generally opposed repressive protest policing. However, certain protest tactics increased support for repression by increasing public fear. Protest goals (e.g., pro-Black Lives Matter, anti-COVID-19 restrictions, or pro-confederate monuments) also impacted support for repression, but the effect depended on respondents’ racial beliefs.