The Effect of Civilian Casualties on Wartime Informing: Evidence from the Iraq War

Scholars of civil war and insurgency have long posited that insurgent organizations and their state enemies incur costs for the collateral damage they cause. We provide the first direct quantitative evidence that wartime informing is affected by civilian casualties. Using newly declassified data on tip flow to Coalition forces in Iraq we find that information flow goes down after government forces inadvertently kill civilians and it goes up when insurgents do so. These results confirm a relationship long posited in the theoretical literature on insurgency but never directly observed, have strong policy implications, and are consistent with a broad range of circumstantial evidence on the topic.