Background – In New Zealand, it is often claimed that outlaw motorcycle gangs control the illegal markets for methamphetamine and cannabis, including purposively suppressing the local availability of cannabis to encourage sales of the more profitable methamphetamine.
Aims – (1) Explore predictors of higher levels of gang involvement in retail illegal drug markets. (2) Investigate whether higher levels of gang involvement and number of gangs are predictors of differences in the price, potency and accurate sale weight of different drugs types compared to lower levels of gang involvement.
Methods – An online convenience drug survey (NZ Drugs Trends Survey) was broadly promoted via Facebook™ from November 2018 to March 2019 (n=10,966). Respondents were asked to what extent gangs control the sale each drug type (1=none-5=only gangs), how many different gangs were selling in the area (1=many-4=one), and how price, potency and weight provided by gangs compared to non-gang sellers.
Results – Region was a significant predictor of extent of gang involvement in drug selling. Higher methamphetamine availability and conversely lower cannabis availability was associated with higher gang involvement. Higher relative price of cannabis was positively associated with extent of gang involvement and lower number of different gang sellers. Lower sale weight of cannabis was positively associated with greater gang involvement and lower number of different gang sellers. Weaker cannabis potency was associated with lower number of different gang sellers.
Implications - Economic theory of monopoly and marketing offers important insights into these findings.