What caused the recent reduction in heroin supply in Australia?

Heroin availability and purity decreased and prices increased in Australia suddenly in early 2001. The heroin market in Australia has still not returned to the status quo ante after more than six years. Benefits of the heroin shortage, including a substantial reduction in drug overdose deaths and property crime, are generally considered to have outweighed adverse effects which included increased use of other drugs, especially stimulants, with a subsequent increase in aggression, violence and mental illness. Some commentators attributed the heroin shortage to a combination of factors, while an influential study highlighted the importance of supply control asserting that increased funding and improved effectiveness of domestic drug law enforcement produced critical heroin seizures which disrupted major syndicates, thereby producing the heroin shortage. Evidence to support a critical role for drug law enforcement in the heroin shortage is weak with some recent evidence contradicting key assertions used to support the supply control hypothesis. Although the most likely interpretation is still a combination of multiple factors, the most important factors appear to have been a substantial recent reduction in source opium cultivation and heroin production in Burma, but probably also increased heroin consumption en route through China and a switch from heroin to amphetamine production in Burma. This interpretation is consistent with the international experience of several recent decades in numerous countries where national heroin shortages have occurred rarely and generally only briefly, notwithstanding vigorous and very well resourced supply control efforts. The recent reduction in heroin supply in Australia, the most severe, longest lasting and best-documented heroin shortage in the world, cannot be confidently attributed, solely or largely, to improved domestic drug law enforcement. At best, domestic law enforcement may have made a small contribution compared to several other factors. Evaluation of supply, demand and harm reduction should be held to the same standards.