Are peaceful or violent protests more effective at achieving policy change? I study the effect of protests during the Civil Rights Era on legislator votes in the US House. Using a fixed-effects specification, my identifying variation is changes within the congressional district over time. I find that peaceful protests made legislators vote more liberally, consistent with the goals of the Civil Rights Movement. By contrast, violent protests backfired and made legislators vote more conservatively. The effect of peaceful protests was limited to civil rights-related votes. The effect of violent protests extended to welfare-related votes. I explore alternative explanations for these results and show that the results are robust to them. Congressional districts where incumbents were replaced responded more strongly. Furthermore, congressional districts with a larger population share of whites responded more strongly. This is consistent with a signaling model of protests where protests transmitted new information to white voters but not to black voters.