In Australia a vicious debate on cannabis policy started when Alex Wodak, the head of the Sydney drug and alcohol clinic at St Vincent's Hospital, suggested that marijuana be regulated like alcohol or tobacco. He proposed to sell cannabis legally in post offices in packets that warn against its effects.
Cut cannabis use by selling it at the post office, Wodak said. Australia needed to learn from the tobacco industry and the US Prohibition era in coming to terms with his belief that cannabis use would replace cigarette consumption over the next decade. "The general principal is that it's not sustainable that we continue to give criminals and corrupt police a monopoly to sell a drug that is soon going to be consumed by more people than tobacco."
The suggestion was opposed by Mrs Miranda Devine in an OpEd in the Sydney Morning Herald, claiming that legalising cannabis would create more cannabis users and more mental health problems. Wodak replied in a letter, where he showed that Devine’s assertion was not backed up by research and quoted two major reviews of the experience of countries before and after liberalisation that concluded that cannabis consumption remained unchanged or decreased.
Devine replied in a vicious OpEd, repeating her claims and suggesting that Wodak should be removed from St Vincent's Hospital: “The question still needs to be asked of the Sisters of Charity: how do you solve a problem like Alex Wodak?,” she wrote.
Wodak tried to reply but the Sydney Morning Herald declined to publish his letter. Below we publish Alex Wodak’s open letter, which again convincingly shows that regulating cannabis would not create more cannabis users and more mental health problems.
An Open Letter to Ms Miranda Devine from Dr Alex Wodak
A shorter version of this letter (without references) was offered to the Sydney Morning Herald but declined. This commentary is a response to arguments made in an article by Ms Devine published in the Sydney Morning Herald on 15 May 2008.
REDUCING THE HARMS OF CANNABIS AND CANNABIS POLICIES
In her recent article on cannabis in the Sydney Morning Herald , Ms. Miranda Devine expressed three main concerns about taking this drug out of the domain of law enforcement and into the domain of public health. Firstly, that a public health approach will inevitably increase cannabis use in Australia at a time of declining consumption. Secondly, that cannabis increases psychosis. Thirdly, that the Swedish zero tolerance approach demonstrates best how to reduce illegal drug consumption. Some support for each of these views may be adduced from partial quotation of selected research and opinions, including a recent letter  to the Sydney Morning Herald by Dr. Don Weatherburn and Professor Wayne Hall. However, a thorough review of research to date does not support Ms. Devine’s case.
Assertions that cannabis use is certain to increase if the drug is taxed and regulated are just beliefs, no doubt strongly held, but unsubstantiated beliefs nonetheless. A European comparative study and an overview of research conducted in the USA and Australia found  no convincing relationship between drug policies and prevalence rates of cannabis use. In his evaluation of the effects of the 1987 partial decriminalisation on cannabis use in South Australia, Professor Hall concluded  that the increase in consumption in South Australia was not significantly greater than the average increase in the other three states included in the study.
Ms. Devine cited criticism  by Weatherburn and Hall of a study by Reinarman, Cohen and Kaal comparing  cannabis consumption in San Francisco and Amsterdam as evidence against my views. Weatherburn and Hall argued that differences in demographics may have explained the higher consumption in San Francisco. But it is clutching at straws to believe that the small demographic differences that were found in this study can explain a more than three-fold greater prevalence of smoking cannabis in the city with the more punitive approach. The study also found that the prevalence of use of every other illicit drug was dramatically higher in San Francisco. National surveys in both countries consistently confirm these same differences. If the peer reviewers for the top public health journal in the world had considered demographic differences to be a serious limitation of the study, they would have demanded that the authors indicate this.
Weatherburn and Hall are correct that the samples were not exactly matched. But both were rigorously random, representative samples of experienced users in the household populations of the two cities and the survey instruments and measures used were identical.
The fact that the findings of this study were consistent with virtually all other studies in showing that the great majority of cannabis users clearly reduce use or cease altogether as they get older suggests that the slightly higher average age of the San Francisco respondents was more likely to have reduced use in San Francisco relative to Amsterdam rather than to have increased it. Dr. Weatherburn and Professor Hall have it backwards.
These researchers also appear to cite the comparative study selectively. They did not mention that the slightly higher likelihood of unemployment in the two years before the study was conducted in San Francisco was most likely due to temporary problems of the high technology industry at the time of the study. It is difficult to believe that Weatherburn and Hall could argue that this temporary slightly higher unemployment explains the threefold higher cannabis consumption found in San Francisco.
It is also misleading for these researchers to claim that ‘consumption increased substantially in the Netherlands after the creation of a de facto legal market’. While cannabis use did increase in the Netherlands at that time, it also increased in almost every other Western country where cannabis prohibition was continued. In some countries, cannabis consumption increased even more than in the Netherlands. Thus, the causal claim that these respected researchers make is too simplistic. Cause cannot be established without proper comparisons and when these comparisons are made, the increase in use cannot be solely attributed to the de facto decriminalization of cannabis in the Netherlands.
Although Dr. Weatherburn and Professor Hall say in their letter that ‘in research in NSW, most regular cannabis users say they would use it more often if it was legal’, Weatherburn’s own study suggests otherwise. Weatherburn and a colleague concluded  ‘that two-thirds of respondents definitely wouldn't use more cannabis if it were made legal. The remainder, however, would not rule out using cannabis more frequently if it were legal. Four per cent of the sample said they definitely would use more cannabis, about 10 per cent said that they would probably use more and about 19 per cent said that they probably wouldn't use more but, nonetheless, did not rule out the possibility’.
The Police Foundation of the United Kingdom noted  in their ‘Drugs and the Law’ report in 2000 that ‘the consequences of drug use are more important than the numbers of users.’ Quite so. The fundamental principle of harm reduction is that reducing harm is more important than a single minded focus on reducing consumption, whatever the cost. Drug law enforcement authorities in Australia have also questioned  the wisdom of harsh penalties for cannabis use noting ‘[cannabis offences] … absorbed a significant proportion of resources dedicated to drug law enforcement. In addition, in contrast to most other illicit drug use, there appears to be a comparatively low rate of associated crime and harm to other individuals and the community. The decriminalisation of personal cannabis use and production may greatly reduce both police and legal resource expenditure’.
Policy determination must include a balancing of benefits and costs. That is why the costs of cannabis prohibition should not be ignored. According to Professor Hall, the costs of cannabis prohibition include ‘the creation of a large black-market; disrespect for a widely broken law; harms to the reputation of the unlucky few cannabis users who are caught and prosecuted; lack of access to cannabis for medical uses; and an inefficient use of law enforcement resources’ . Ms. Devine makes much of my somewhat facetious comments about the realistic options for selling cannabis. But she does not acknowledge the current realities: cannabis is now sold on the black market with no health standards or regulation. Ms. Devine should explain why she prefers cannabis to be sold with no health standards or regulation.
Despite Ms. Devine’s conviction that a causal relationship between cannabis use and mental illness is only questioned by drug law reformers, debate continues among experts. Professors Louisa Degenhardt and colleagues found  a ‘steep rise in the prevalence of cannabis use in Australia over the past 30 years’ but ‘no evidence of a significant increase in the incidence of schizophrenia’. They concluded that ‘cannabis use does not appear to be causally related to the incidence of schizophrenia, but its use may precipitate disorders in persons who are vulnerable to developing psychosis and worsen the course of the disorder among those who have already developed it.’ If cannabis use is associated with a significant risk of causing or worsening serious mental illness, why does Ms. Devine prefer cannabis to be sold only by criminals or corrupt officials?
Ms. Devine’s conviction  that Sweden demonstrates ‘that prohibition is the most certain way to reduce drug use’ is shared by few others. What matters more: drug use or drug-related harms? For example, the rate of drug overdose deaths in Sweden (16.9/million) is more than twice that in the Netherlands (7.5/million) . Not so long ago, all Scandinavian countries had the same drug policy. Now Sweden is the last Scandinavian country and among the last countries in Western Europe to reject harm reduction. In 2006, the UN Special Rapporteur on the Right to Health visited Sweden and specifically recommended  to the UN General Assembly that: ‘[T]he Government has a responsibility to ensure the implementation, throughout Sweden and as a matter of priority, of a comprehensive harm reduction policy, including counselling, advice on sexual and reproductive health, and clean needles and syringes’.
But surely if country comparisons with Australia are to be made, we should compare ourselves with a country that shares many of our social, economic, cultural, linguistic and political characteristics: the United States of America. In contrast, Australia has little in common with Sweden. Why does Ms. Devine chose to compare drug outcomes in Australia only with Sweden rather than with the United States of America? After all, Sweden and the United States of America both reject harm reduction and prefer zero tolerance. The US Congress even passed legislation in 1988 mandating that the country would become drug free by 1995. The reason is obvious. Drug-related deaths, disease, HIV, crime and corruption are out of control in the USA. With 737 prisoners per 100,000, the USA has the highest incarceration rate in the world - five times higher than Australia - and more than a third of these inmates are serving sentences for drug related offences. Ms. Devine compares only drug use in countries. But surely drug-related harms count for more than just drug consumption? While the relationship between levels of consumption of legal drugs and drug-related harms is clear both for individuals and communities, the relationship between levels of consumption of illegal drugs and drug-related harms is anything but clear.
Although Ms. Devine quotes Professor Hall approvingly, she should be aware that in 2007, and with important caveats, he advocated  ‘a limited legal cannabis market’ accompanied by ‘grudging tolerance’. Such a system would presumably need to include the same limiting measures I have advocated: taxation, strict regulation of cultivation and sale, health warnings, consumer quality controls, age restrictions on sale and assistance for users when trying to quit. No policy is ever going to be perfect but this approach is surely less costly to the community and less harmful to cannabis consumers than just leaving the market to the Al Capones of this world as Ms. Devine appears to favour.
The wisdom of the decision to include cannabis with the global prohibition of opium poppy and coca plant in the 1961 Single Convention is now being increasingly questioned. The UNODC, the major organization implementing drug policy on behalf of the UN system recently acknowledged  ‘either the gap between the letter and spirit of the Single Convention, so manifest with cannabis, needs to be bridged, or parties to the Convention need to discuss redefining the status of cannabis’.
Is the idea of cannabis taxation really so outlandish? After all, US Congress enacted the Marihuana Tax Act in 1937. This remained legislation until 1970. As recently as 2005, 500 US economists (including Professor Milton Friedman and two other Nobel Prize winners) published  an Open Letter to leading politicians including the President and members of Congress calling for the taxation of cannabis.
Ms. Devine is right  that Britain recently reclassified cannabis from Class C to Class B (where Class A drugs are considered the most dangerous, Class B intermediate and Class C least dangerous). This was the first time that the British Government had ignored the views of its expert advisory body (the Advisory Council on the Misuse of Drugs). The UK police then announced that they would not change policing practices on cannabis because of this reclassification. Also, cannabis use had declined in the UK after cannabis was classified from Class B to Class C. Does Ms Devine believe that symbolism trumps outcomes or the reverse?
Ms. Devine expressed concern  that Australia ‘ranks in the top 10 drug users of 193 nations in the UN's 2007 World Drug Report’. But the Howard government introduced a ‘Tough on Drugs’ policy in 1997 and continued this policy until it lost office in 2007. Is the high ranking for drug consumption in Australia explained by the Howard government not being tough enough on drugs or does a supposedly tough drug policy have little impact on drug consumption even after ten years?
One of the hallmarks of a poor argument and weak evidence is the use of personal attacks. Ms. Devine shows the weakness of her case by her reliance on gratuitously personal attacks on myself and my 26 years of practice, research and advocacy in this field.
Dr Alex Wodak,
Australian Drug Law Reform Foundation, Darlinghurst, NSW 2010
 Ms. Miranda Devine, Puff goes the drug liberalizer, Sydney Morning Herald, 15 May 2008
 Dr. Don Weatherburn, Professor Wayne Hall. Mismatch on dope figures (Letters) Sydney Morning Herald, 13 May 2008
 V. Maag. Decriminalisation of cannabis use in Switzerland from an international perspective - European, American and Australian experiences. International Journal of Drug Policy. 2003; 14 (3); 279 - 281.
 Neil Donnelly; Wayne Hall; Paul Christie. The effects of the Cannabis Expiation Notice system on the prevalence of cannabis use in South Australia: evidence from the National Drug Strategy Household Surveys 1985-95. Drug and Alcohol Review. 2000; 19 (3); 265-269.
 Reinarman C, Cohen PD, Kaal HL. The limited relevance of drug policy: cannabis in Amsterdam and in San Francisco. Am J Public Health. 2004; 94(5): 836-42.
 Don Weatherburn, Craig Jones. Does prohibition deter cannabis use? Number 58, August 2001. Contemporary Issues in Crime and Justice. Crime and Justice Bulletin.
 Drugs and the Law: Report of the Independent Inquiry into the Misuse of Drugs Act 1971. The Police Foundation, London, 2000.
 The Australian Bureau of Criminal Intelligence. Australian Illicit Drug Report 1996-97.
 Wayne Hall. Reducing the harms caused by cannabis use: the policy debate in Australia. Drug and Alcohol Dependence. 62 (3); 163 - 174.
 Louisa Degenhardt, Wayne Hall, Michael Lynskey. Testing hypotheses about the relationship between cannabis use and psychosis. Drug and Alcohol Dependence. 2003. 71 (1); 37- 48.
 European Monitoring Centre for Drugs and Drug Addiction, 2007 Annual report, Table DR5 Part (i)
 Wayne Hall. A cautious case for cannabis depenalisation. pp 91-112. Pot Politics. Marihuana and the costs of prohibition. (ed) Mitch Earleywine. Oxford University Press 2007.
 United Nations Office on Drugs and Crime, 2006 World Drug Report