Drug Abuse

5. Consequences of the options

5. Consequences of the options

Since only some of the options considered have ever actually been implemented (the models based on the current regime of prohibition), the following discussion of consequences can be founded only in very small part on empirical research data. Instead we are restricted to evaluating circumstantial evidence and drawing inferences. The only way to remedy this state of affairs would be by implementing particular models as pilot projects with proper scientific monitoring and evaluation, along the lines of the Schleswig- Holstein initiative for the sale of cannabis in pharmacies. The consequences are considered under the following headings: changes in risk awareness and consumption propensity, changes in consumption and consumption patterns, changes in the effects of consumption, consequences for the illegal cannabis market, need for new regulation and political consequences.

5.1 Change in consumption propensity

A criticism which is raised in respect of all the alternatives to the current regime of prohibition is that they could lead to a proliferation in cannabis consumption, since the general preventive effect of prohibition would have been removed (Logan 1979). In the following sections this assumption is critically examined in relation to each of the models.

5.1.1 Removal of the offence of consumption (see section 4.2.3)

In its report on the consequences of liberalization the Munich- based Institut für Therapieforschung concludes that the volume of consumption would rise in rough proportion to the degree of liberalization (IFT 1995). By analogy with the growth in alcohol consumption that took place as social controls of alcohol were relaxed, the IFT foresees consumption rising to reach similar levels to those of alcohol and tobacco consumption. Against that, it must be observed that the prohibition of consumption is only a minor factor in young people choosing not to take cannabis; health concerns play a far greater role in this (Bundeszentrale für gesundheitliche Aufklärung 1994). A similar conclusion was arrived at in an earlier US study (Johnston et al 1984). A comparative analysis of countries in which consumption is and is not outlawed shows that there is no direct correlation between prohibition and the incidence of consumption (measured by prevalence statistics). A more valuable indicator would be an analysis of consumption prevalence figures before and after the decriminalization of consumption and of activities associated with personal consumption. But no prospectively designed, systematic study of consumption patterns before and after such a change in the law and enforcement practice has ever been carried out. The figures available show only that the prevalence of current cannabis consumption is not directly correlated to the presence or absence of a criminal sanction for consumption. The possibility of a general and sustained rise in consumption as a consequence of the lifting of the prohibition of consumption cannot therefore be ruled out but nor is such a development very likely. Instead, one might expect a temporary rise in curiosity consumption which, however, would not necessarily result in a rise in the number of long- term users; the majority of those who experiment do not become regular users and over time the overall level of consumption tends to fall rather than rise (Sieber 1988, Kleiber and Soellner 1998). It should also be noted that there has been a sharp rise in cannabis consumption propensity in Germany in the period up to 1995, even moreso in the former East Germany than in the former West (Kraus et al 1998), without there having been any change in the legal status of the drug. This indicates a change in attitudes towards cannabis, the effect of which has been to boost consumption. Over the same period (1990- 1995) actual consumption rates increased by a factor of between two and three – but only among males (Kraus et al 1998). The increase in consumption propensity was highest in the 21- 24 age group (Simon et al 1997). But since 1995, despite the higher consumption propensity, actual consumption rates have stabilized and to some extent fallen back (Kraus and Töppich 1998).

In Switzerland too, there has been evidence available for some time that consumption propensity is less influenced by the legal status of the substance in question than by the perceived risks and by subjective feelings (Hornung et al 1983). More recently, surveys of school- children show that health risks, fear of dependency and of personality change, together with financial considerations are far more frequently given as reasons for abstinence than the fact that drugs are illegal (Müller et al 1997). Despite both cannabis and heroin, for example, having the same status in the eyes of the law, not only the actual prevalence figures but also the reported consumption propensity for the two substances are very different. This is largely accounted for by the fact that heroin carries a higher risk of addiction and damage to health. Thus the low propensity for heroin consumption associated with the perceived health risks of that substance contrasts with the higher propensity for cannabis consumption based on the perception of a far lower health risk, despite the fact that both substances are equally unlawful. There is nonetheless a fear that removing the prohibition would send the 'wrong signal' and convey the impression that cannabis is harmless. There is a possibility, which cannot be rejected out of hand that, in the event of cannabis becoming legally available and product safety improving accordingly, the perceived risk of cannabis use would diminish further leading to a rise in consumption propensity. The point has therefore been rightly made that any change in the legal status of cannabis should be accompanied by intensive preventive measures in order to counteract any such mistaken interpretation. Another consideration to be borne in mind is that the prohibition of consumption produces a degree of caution in users, with the result that consumption tends to take place in the private domain or in an environment where users are safe in the knowledge that they will not be discovered or reported to the authorities. The removal of the prohibition of consumption could thus have the effect of leading to an increase in public consumption. In some countries (e. g. Spain) it was therefore regarded as important to restrict the lifting of the prohibition to the private domain. Potential consequences of a proliferation of public consumption would be, first, to increase the attractiveness of consumption for others and, secondly, to create a problem with ambient smoke, the reduction of which is a current concern with regard to cigarette smoke.

5.1.2 Change in the severity of penalties (see section 4.2.4)

The same criticism as above is also made in relation to any reduction in penalties for consumption, possession, purchase and supply: that it could result in a weakening of the general preventive effect generated by harsher penalties. The example of the USA, in which the severity of penalties varies enormously from state to state without any corresponding divergences in the prevalence figures, shows that there is no systematic correlation between the scale of sanctions and the incidence of potential offences. It has to be borne in mind that the numbers of prosecutions and convictions is influenced by several factors, including the intensity of the police effort, the resources available for the purpose and, of course, the actual incidence of drug law violations. A prospectively designed and systematic study of the effects of an increase or reduction in penalties has yet to be carried out. The figures currently available do not support the conclusion that a reduction in the severity of sanctions results in an increase in consumption.

5.1.3 Introduction of a system based on the expediency principle (see section 4.2.5)

The figures available from the Netherlands show that while the prevalence of cannabis consumption rose sharply during the seventies, as it did in many other countries too, in recent years there has been a leveling off and even a decline. On the other hand, the estimated quantity of cannabis produced in the Netherlands has mushroomed. It is believed that the importation of cannabis, which is illegal and still liable to be prosecuted, has decreased accordingly, but this is naturally only conjecture. In the coffee shops, at any rate, the proportion of imported cannabis has fallen in favor of produce grown in the Netherlands. There is also some evidence in the Netherlands of the emergence of an unwanted export trade in cannabis. Establishing the quantity of the substance being produced in the so- called grow- shops and how much of that is being exported is posing a fresh challenge for the Dutch authorities. However, this has not resulted in the application of the expediency principle to cannabis dealing and consumption being called into question (Jansen 1998).

5.1.4 Medical prescription (see section 2.5)

Prescription for medicinal purposes, as considered above, relates to a very restricted group of persons, perhaps no more than isolated cases. It could therefore, by its very nature, be expected not to influence prevalence rates. That would only be likely to occur if the prescription grounds were to be extended to include considerably more – and less serious – medical conditions. But there is no demand for such a measure, nor is there any rationale to justify it. A system based on prescription by doctors for non- medicinal purposes has not been implemented in any jurisdiction and there is consequently no means of judging its effects. Resistance to such an approach on the part of both users and medical practitioners would be likely to constitute a major obstacle.

5.1.5 Licensing of suppliers (see section 4.3.3)

One of the purposes of the restrictions to be imposed under a supplier licensing system, as discussed under section 4.3.3 above, would be guard against a potential increase in consumption volumes. Such measures include limiting the number of distribution outlets, taxing sales and imposing restrictions on advertising. To what extent measures such as these are in fact capable of preventing more widespread or more intensive consumption is an open question. Experience with similar forms of regulation in relation to the legal sale of alcohol and tobacco have shown that the removal of restrictive measures, reductions in price and targeted advertising can lead to an increase in consumption.

5.1.6 Controlled purchase (see section 4.3.4)

Part of the rationale for the introduction of a system of authorization for the purchase of cannabis products is to create an inhibition threshold. The registration of users, especially, is a measure likely to deter a fairly sizeable category of potential consumers. The introduction of a quantitative limit for purchase entitlements (rationing) would additionally prevent an increase in consumption. A problem with such measures, as with the imposition of a heavy tax charge, is that by helping to maintain an illegal parallel market in existence their effect may be counterproductive vis- à- vis their stated aim of prevention.

5.1.7 Free availability (see section 4.3.5)

Here as in the case of a licensing system the importance of accompanying restrictive measures must be emphasized. Without such restrictions the probability of a rise in consumption is far greater. Of particular significance in this regard are product requirements: the prohibition of manufactured cannabis cigarettes would have an especially important preventive function.

5.2 Changes in consumption and consumption patterns 5.2.1 Removal of the offence of consumption (see section 4.2.3)

A key question is whether current users of cannabis would increase the frequency of consumption and the dose size in the event of the prohibition being removed. Here again, the data needed to provide an answer is not available. Nonetheless, it is likely that consumption volumes are limited by various factors, among which the price and quality of the product on offer together with the perceived risks are at least as important as the legal status of consumption. The low risk of being detected for the purchase, possession and consumption of cannabis, even under a regime of prohibition, makes it unlikely that there would be any significant change in the inhibition threshold if the prohibition were to be removed.

5.2.2 Change in the severity of penalties (see section 4.2.4)

There are no studies available which focus on whether cannabis users orient the volume of their consumption according to the severity of the penalties to which they would be liable. This appears less likely than that non- users would be deterred to some extent by heavy penalties. A person who is already a user has already assumed the basic risk. However, it is probable that users exercise a greater or lesser degree of caution depending on the size of the risk. According to an American study, a majority of long- term users are not worried that others could find out about their consumption; those that do not wish their habit to be discovered are concerned primarily about criminal prosecution but also about adverse employment consequences (Erickson 1989).

5.2.3 Introduction of a system based on the expediency principle (see section 4.2.5)

There are no known studies available from the Netherlands into whether the Dutch approach of tolerating retail sale and consumption has led to any change in the consumption patterns and consumption volumes of long- term users.

5.2.4 Medical prescription (see section 2.5)

Under such a system, any increase in the levels of individual consumption would be recorded by the prescribing doctor, assuming multiple prescriptions (by several doctors at the same time) can be excluded. It would then be for the doctor to take action in the light of the increase in consumption.

5.2.5 Licensing of suppliers (see section 4.3.3)

Restrictive measures such as a cannabis tax and advertising curbs would need to be considered, primarily for the purpose of preventing any upsurge in user numbers. Non- users, users out of curiosity and sporadic users are the most receptive targets for such measures rather than those for whom consumption represents a priority (those who have become dependent, for example, in whose case price elasticity can be expected to be low).

5.2.6 Controlled purchase (see section 4.3.4)

With controlled purchase models it is to be expected that a section of users, particularly those who are socially integrated, would endeavor to avoid registration (which would increase the incentive for a parallel black market). Other users who had already come to the attention of the authorities and been registered would on that account be more likely to submit to registration. A similar pattern is found with opiate addicts, of whom about half those in Switzerland are estimated to be in substitution treatment and therefore registered, while perhaps an almost equal number remains underground and avoids contact with official agencies.

The added purpose served by a rationing model is to prevent an increase in consumption volumes per user. When an alcohol rationing system (the Bratt System) was introduced in Sweden it led to a reduction in the statistics for alcohol- related problems (delirium tremens, cirrhosis of the liver, accidents caused by the effects of alcohol), but was costly to operate and could be circumvented by means of purchases on the black market.

5.2.7 Free availability (see section 4.3.5)

In a scenario of unrestricted availability, an increase in the frequency of use and dose sizes among habitual users is a risk which cannot be excluded.

5.3 Changes in the effects of consumption

Studies of varying quality have been carried out into the adverse health and social effects – both acute and chronic – of cannabis consumption. A summary of the findings can be found in the latest experts' report commissioned by the German Federal Ministry of Health (Kleiber and Kovar, 1998). There are other recent summaries of the findings by Hall et al 1994, Hall 1998, Hall and Solowij 1998, Solowij 1998, and Zimmer and Morgan 1997. An exhaustive systematic review of the scientific literature has been published by Waller et al (1990, 1994, 1995). Without embarking on a detailed examination of the various risks involved, the situation may be summarized as follows:

No cases of death from overdose have been substantiated
The extent of beneficial or harmful effects is extremely variable, depending on the survey sample
The probability of adverse effects occurring increases with higher frequency and greater intensity of consumption (dose per consumption)
In relation to mental disturbances suffered by cannabis users the prevailing view is that personality factors are just as important as the effects of the substance

Certain groups are especially vulnerable to adverse consequences: young people, the mentally unstable, pregnant women, sufferers from heart and lung disease. An issue which has still to be adequately resolved is the relationship between cannabis use and the onset of schizophrenic psychoses. On the one hand, studies have shown that in subjects who have been using cannabis regularly schizophrenic psychoses tend to occur earlier (Linszen et al 1993, Caspari 1998) and more frequently (Andreasson et al 1987). On the other hand, cannabis is taken by schizophrenia sufferers to alleviate negative symptoms and the side effects of neuroleptic drugs (Schneier and Siris 1987, Dixon et al 1990). But continued cannabis use has also been shown to be associated with a higher relapse rate for psychotic symptoms (Linszen et al 1994, see also section 2.3.4). Not all heavy daily users of cannabis experience serious negative consequences. There is even some evidence that such users find it easier to 'function' on a day- to- day basis, but at the price of losing the ability to address and resolve problems which ought to be addressed and resolved (Hendin et al 1987). As discussed above, frequency of consumption can be increased by promotion and marketing, reduced risk awareness and the availability of easy- to- use products (prefabricated cigarettes and food products). Intensity of consumption (dose per consumption), on the other hand, can be increased by the supply of products with a high content of active principle. The risk of accident depends above all on the degree of caution exercised by cannabis users when under the influence of the drug; the cautious behavior shown by cannabis users when driving in road traffic (Krüger 1995) may be related to the test conditions but may also have to do with the prohibited nature of the substance. The possibility of an increase in careless conduct in the event of cannabis products becoming legally available cannot therefore be discounted. The conclusion to be drawn is that the negative effects of cannabis consumption can best be prevented if cannabis products cannot be sold at a large profit, if products with a high content of active principle are prohibited and if particularly vulnerable individuals receive appropriate advice. In addition, if cannabis products are to be made more easily available, general prevention activities and measures to protect the young will need to be stepped up. The legal availability of cannabis, whatever form it takes, will result in one specific problem: the cognitive impairment caused by the acute effects of cannabis leads to an increased risk of accident both when driving and in other hazardous situations at the workplace or during leisure activities (Solowij 1998). This necessitates not only appropriate preventive measures but also the imposition of a legal limit on motorists’ blood- THC. A maximum level for the legally permissible THC- content in the blood of motorists will have to be defined and demonstrated. Studies of driving behavior in a driving simulator have yielded useful material in this regard. Still to be resolved is the problem of coming up with a practical and inexpensive means of determining blood- THC- content.

5.4 Consequences for the illegal cannabis market

The main consideration here is that an appreciable decline in the market for illegal cannabis is likely only if it becomes sufficiently attractive to consumers to switch to legal sources of supply. Restrictive measures of the type discussed above may in given circumstances have counterproductive effects. What is needed is an appropriate balance between restrictive measures on the one hand and the attractiveness of the legal cannabis market on the other, but it is difficult to predict what would and would not be found acceptable by the sections of the population concerned. Views on what is acceptable are also liable to change. Some degree of flexibility should therefore be built into the measures and their operation monitored in order to document their intended and unintended effects, so that they can be modified if necessary.

5.5 Need for new regulation

If a legal market is to be created for cannabis products new regulations will be necessary. At this point we need mention only road traffic regulations, product requirements, advertising restrictions, the criteria to be met by distribution outlets, etc. Provisions will also have to be adopted under the food legislation regarding which cannabis- containing products will be authorized and with what active principle content. It is not possible here to give an exhaustive list of the legislative and other measures that will be required. That will depend largely on which of the specified options is chosen.

5.6 Political consequences

What makes the current situation anomalous and a cause for concern is the gulf that separates the present state of the law from everyday reality, giving rise to repeated calls for a review of policy on cannabis. However, the consequences of implementing an alternative policy are by no means easy to predict. Ideas as to what should best be done in this situation thus constitute a palette of contrasting approaches, such as proposals for far- reaching legalization under a licensing model (Schneider 1995) as opposed to more cautious recommendations involving a reduction of the criminal penalties for consumption and activities preparatory to consumption (McCoun and Reuter 1998). In view of the prominence of the drugs issue at home and abroad, a change in cannabis policy and legislation is bound to provoke controversy in relation to drug, health and social questions. The impact on other countries has to be taken into account – they may come under pressure to follow suit or may have to contend with a increase in cannabis imports and consumption or with 'drug tourism' to Switzerland on the part of their drug users. On the domestic front, there are likely to be misunderstandings and misinterpretations that could jeopardize the continuation of the present consensus on drug policy, of which the public is part. The only way to address potential consequences of this kind is by making the necessary preparations so as to provide ample information, to promote factually- based public debate and to get across the purpose and aims behind the new policy. Nobody can say for sure what the consequences of a change in cannabis policy will be. An important preliminary task is therefore to draw up a blueprint for ongoing documentation and evaluation of the measures which are taken; to enable the effects of the changes to be gauged, a proper framework for recording findings must be in place before implementation of the changes begins.

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