Supply-side reduction policy and drug-related harm

Monograph no. 53

Wai-Yin Wan, Don Weatherburn, Grant Wardlaw, Vasilis Sarafidis, Grant Sara

The three pillars of Australia’s drug policy are: supply reduction; demand reduction; and harm reduction. Supply reduction policy focuses on reducing the supply, or increasing the cost of, illegal drugs through such actions as crop eradication, drug seizures, arresting drug importers and distributors etc. While there is much evidence to support the effectiveness of demand and harm reduction measures, there is less evidence supporting the effectiveness of supply reduction policy.

The purpose of this study was to improve on, and further contribute to this area of knowledge and examine the impact of seizures and supplier arrest on the use and associated harms of three drugs: heroin, cocaine, and amphetamine type substances (ATS).

The investigation had two parts. The first sought to determine whether there was an inverse relationship between the intensity of supply reduction efforts (as measured by seizure weights and frequencies and by supply arrests) and:
  1. The number of emergency department (ED) admissions or drug use/possession (UP) arrests which were attributed to heroin, cocaine, or ATS use; or
  2. The reported incidence of certain drug related offences known or thought to be committed by users of heroin, cocaine, or ATS (such as theft, robbery, and assault).

The investigation was limited to the top 20 per cent of seizures by weight. The time lag between the supply reduction efforts and the outcomes examined in this part of the study was four months. This part of the study covered the 10 year period from July 2001 until June 2011.

The second part involved an examination of the impact of three specific operations (Operation Balmoral Athens, Operation Tempest and Operation Collage) identified by the NSW Crime Commission as having the potential to have affected the market for cocaine. Because the three operations occurred is close succession they were treated as one single intervention.