The structure and vulnerability of a drug trafficking collaboration network

• The structure of a heroin trafficking network is analyzed.
• Similar topology to non-criminal collaboration networks.
• Trafficking network exhibits dissortative degree mixing.
• Graph sampling has been applied.
• Vulnerability of network to targeted vertex removals is assessed.

Prior research has established that collaboration networks exhibit heavy-tailed degree distributions, assortative degree mixing, and large clustering coefficients. Using court record data, we assess these properties in a collaboration network among heroin traffickers. Consistent with prior research, we find an exponential degree distribution and strong local clustering. However, the traffickers mix dissortatively by degree rather than assortatively. Using a graph sampling method, we show that a consequence of dissortative mixing is that targeted vertex removals have a greater impact on the connectivity and cohesion of the trafficking network. We also note the importance of degree mixing for characterizing and identifying topological weaknesses.