Fatality Thresholds, Causal Heterogeneity, and Civil War Research: Reconsidering the Link Between Narcotics and Conflict

Abstract

Determining the appropriate fatality threshold criteria for case selection in the civil war literature has proven contentious. Yet, despite continued debate, our survey of the literature finds that scholars rarely examine their findings across multiple thresholds. Of those that did evaluate their findings in this way, nearly half found that their results changed at different thresholds. Because minor and major conflicts often exhibit different causal patterns, scholars should explore their empirical findings across a range of theoretically motivated thresholds. To illustrate the utility of this approach, we demonstrate that the relationship between narcotics and conflict intensity varies across thresholds. We then introduce a dynamic theory that emphasizes the endogeneity of rebel groups’ decisions to turn to drug cultivation during civil war.