Murder by Numbers: Socio-Economic Determinants of Homicide and Civil War

Deliberate killing is a common part of the defining features of both homicide and civil war. Often, the scale of killing is also similar: most countries have homicide rates that exceed the threshold of one thousand combat-related deaths during a year that is the standard criterion for civil war. What is clearly different is the organization of killing: the perpetrators of homicide are usually individuals or small groups, whereas rebellion – the direct cause of a civil war - requires a cohesive group of at least several hundred killers. Beyond this, the motivation for the two types of killing may differ systematically, although evidently both homicide and rebellion have many different motivations, including error and irrationality. In this paper we investigate whether the socio-economic determinants of homicide and civil war are similar, and then explore potential inter-relationships between them. We compare our existing model of the risk of civil war with a new model of the homicide rate. We find that there is a ‘family resemblance’ between the two types of killing, but surprising differences. Furthermore, we turn to the inter-relationships between homicide and the risk of civil war. Specifically, we ask whether a high rate of homicide makes a country more prone to civil war, and whether a civil war makes a country more prone to homicide. Our results indicate that higher homicide rate do not increase the risk of war but that civil wars generate a legacy of increased post-conflict homicide rates.