Over the past two decades, there has been growing scholarly interest in nonviolent resistance—a method of conflict in which unarmed people mobilize collective protests, strikes, and boycotts in a coordinated way. Mass movements that rely overwhelmingly on nonviolent resistance sometimes feature unarmed collective violence, fringe violence, or even organized armed action. What do we know about the effects of violent flanks on movement outcomes? This article reviews findings on the relationships between nonviolent and unarmed resistance, violence, and the outcomes of mass mobilization, as well as the directionality of these relationships. The balance of empirical evidence suggests that organized armed violence appears to reduce the chances for otherwise nonviolent movements to succeed, whereas unarmed collective violence has more ambiguous effects. The field will benefit from greater analytical precision in comparing the units of analysis, scope, intensity, and media framing of violent flank activity.
Chenoweth, Erica. "The Role of Violence in Nonviolent Resistance." Annual Review of Political Science 26 (June 2023): 55-77.