Repressive state violence, intended to tamp down collective mobilisation, sometimes inspires greater participation by protesters. When popular and/or elite reactions cause the repressing party to concede, civil resistance scholars define the failure of state repression as ‘backfire’. Some have proposed that movements’ nonviolent discipline is essential to backfire. This article demonstrates that movements that practise ‘unarmed militancy’ – forceful, combative tactics less damaging than armed violence – can also succeed through backfire, achieving policy concessions and even presidential resignations, and presents a qualitative comparative analysis of the outcomes of 48 protest events with multiple deaths in Bolivia between 1982 and 2019, and a case-based analysis of how either movements or repressors prevailed. Movements that confronted deadly repression succeeded in 57–8 per cent of cases. Whether or not protesters engaged in lethal defensive violence did not affect their likelihood of success. However, state repression of guerrillas and paramilitary groups, and during polarised partisan conflicts, was consistently successful. Current understandings of backfire need to be reconsidered in light of successful unarmed militant protest in Bolivia and numerous other locations worldwide.