Table 3 SNA studies of drug trafficking group structure
From: Drug supply networks: a systematic review of the organizational structure of illicit drug trade
Sources from systematic review | Main data source | Country | Focusa | Group type | Drug market | Nodes | Links | Analytics | Findings |
|---|---|---|---|---|---|---|---|---|---|
Bright and Delaney (2013) | Courts—2 related seed cases (prosecution evidence) | Australia | CS-GF | Independent | Meth | 58 | Illicit co-activity | Centrality; descriptive analysis | Network expansion increases visibility of members—degree centralization increased and density decreased as group became more profit-oriented |
Calderoni (2014) | Courts—2 & 3 judgments & invest. evidence | Italy | CS-DC | Mafia | Cocaine | 61 & 73 (individuals with @ least 2 contacts) | Communication about illicit activity | Degree & betweenness centrality | Bosses and traffickers have higher degree and betweenness centrality scores Traffickers and bosses sig. more likely to be arrested but only traffickers are sig. more likely to be convicted |
Calderoni et al. (2014) | Police—electronic surveillance | Italy | CS-DC | Mafia | Cocaine | 65 | Communication about illicit activity | Triangles; Simmelian backbone; degree and betweenness centrality | Drug trafficking networks have less triangles (lower density) than conventional networks Individuals appearing in many triangles are more likely to be key players |
Duijn et al. (2014) | Police—all intel. & co-arrests | Netherlands | Population | Assortment | Cannabis | 793 (subset of cannabis cultivators) | Illicit co-activity & co-arrests | Efficiency; density | People in visible roles, e.g., transport and leadership roles (coordinator, financing, international trade), are central and vulnerable to disruption; not at a social distance from others. Network density increases after disruption attack |
Hofmann and Gallupe (2015) | Courts—records & news reports | Colombia & USA | CS-GF | Cartel | Cocaine | 127 | Regular communication about illicit activity | Degree, closeness, & betweenness centrality; 2-step reach | Leader was involved in daily operations and was the most central |
Mainas (2012) | Police—relational database | Greece | CS-DC | Independent | Mixed | 1554 (principal component) | Regular communication about illicit activity | Path length; k-cores | Drug distribution network structures expand outward from core. Compared to terrorist networks, there is less embedding |
Malm and Bichler (2011) | Police—all intel. & co-arrests | Canada | Population | Assortment | Mixed | 1696 (principal component) | Illicit co-activity & co-arrests | Clustering coefficient; geodesic distance | Drug distribution network exhibit small world properties. Network is low in density compared to simulated networks; therefore, it is flexible |
Malm et al. (2008) | Police—all intel. & co-arrests | Canada | CS-DC | Independent | Cannabis | 376 | Illicit co-activity & co-arrest | Degree, betweenness, & closeness centrality | Leaders of cannabis cultivation network were socially central but geographically distanced themselves from drug production sites |
Morselli (2009) | Courts—3 related cases | Canada | CS-DC | Outlaw Motorcycle Gang | Cocaine | 174 (actors targeted by police) | Communication for illicit purposes | Degree & betweenness centrality | Leaders were not in center of network; rather, mid and lower level members were in center |
Morselli (2010) | Courts—3 related cases | Canada | CS-DC | Independent | Hashish & cocaine | 174 (actors targeted by police) | Communication for illicit purposes | Degree & betweenness centrality | High degree centrality indicated vulnerability in the network and more likely to be arrested Leaders had high betweenness centrality and low degree centrality |
Morselli et al. (2007) | Courts—wiretaps & surveillance | Canada | CS-GF | Independent | Cocaine | 110 (subset implicated in trafficking) | Communication for trafficking purposes | Path length; Degree, betweenness & closeness centrality | Drug trafficking network builds out from core Drug trafficking network has shorter geodesic and higher centralization than terrorist networks Mean centrality in all forms except closeness is higher in terrorist networks Closeness centrality in the drug trafficking network is higher when legitimate actors added Key participants more stable in drug trafficking network |
Morselli and Petit (2007) | Courts—wiretaps & surveillance | Canada | CS-DC | Independent | Hashish & cocaine | 110 (subset implicated in trafficking) | Communication for trafficking purposes | Degree and betweenness centrality | Core decentralization increased as law enforcement targeting increased |
Tenti and Morselli (2014) | Courts—1 court order (wiretaps & surveillance) | Italy | CS-DC | Street Gang | Meth | 242 | Communications about co-offending/illicit co-activity | Density; clustering coefficient | Coordinators occupy central role, high in betweenness and degree centrality Trafficking distribution network (and the groups occupying the market chain) tend to be more decentralized than centralized |
Xu and Chen (2008) | Police—co-offense data | USA | CS-GF | Independent | Meth | 3917 | Co-offending | Path length; clustering coefficient; efficiency. | Drug trafficking networks have higher path lengths, clustering coefficients, and efficiency metrics than terrorist networks |