Dogs and Cats Living Together? Explaining the Crime-Terror Nexus

Why do some terrorist groups cooperate with criminal organizations? This behavior is puzzling because there are reputational reasons for each of these kinds of groups to avoid the other, yet such cooperation seems to be increasingly common. The growing literature on the "crime-terror-nexus" examines terrorist-criminal cooperation, but questions remain. We discuss relevant research, and present hypotheses. Analysis of nearly 400 terrorist organizations using a newly-coded measure of inter-organizational cooperation suggests that certain types of terrorist groups are more likely to work with organized crime: those that are involved in the drug trade, cooperate with other terrorist groups, are older, or are more lethal. These relationships are robust. We also find some evidence that the crime-terror nexus is more likely for groups that have state sponsors, have larger memberships, operate in more capable countries, or operate in less-democratic countries. There is also some evidence that ethnically-motivated terrorist groups are less likely to cooperate with organized crime. Interestingly, there is little or no support for the idea that the nexus is related to territorial control or religious ideology. These findings go against some previous research and suggest steps for future analysis.