Structure and influence in the spread of collective violence

Contradicting 50 years of analysis of urban rioting in the U.S., I connect diffusion notions to structural and economic conditions to show that structural conditions are important in predicting riot occurrence-but in a different way than previously imagined. Using riot and census data from United States in the 1960s, this analysis shows that instead of being directly responsible for producing riots, poor structural conditions increase the chances that the residents of a city will imitate other riots. This distinction is subtle, but means that structural effects are moderated by the prior behavior of other actors: lack of prior rioting depresses effects of structural conditions but as riots accumulate, structural conditions begin to play a role and activate imitation. This suggests that structural conditions alone may not have been enough to invoke rioting, but they provided fertile ground for diffusing riot ideology as the riot wave progressed.