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Precaution or perversion: eight harms of the precautionary principle

David Nutt      

23rd June 2010

The precautionary principle is frequently invoked in relation to drugs laws. The argument goes like this: if we are unsure of the risks of harms of a drug then it is safer to ban it as a precaution rather than wait until harms become apparent. As a principle, it is based on the supposition that since there are assumed to be no benefits of “illegal” drugs then banning them will have no downside or ‘disbenefits’ with the anticipated result that the banning of them will be beneficial to society and to users. 

At face value, the precautionary principle seems reasonable but, as I argued in the Eve Saville lecture at the Centre for Crime and Justice Studies last year, it is fraught with hidden harms and injustices especially if applied in an unthinking and arbitrary manner.

Here are eight examples where the precautionary principle with drugs falls down:

1. Increases personal harms
The penalties enforced in the banning legislation may cause more harm than the drug itself: a criminal record or even imprisonment for cannabis possession will almost certainly be more damaging to the individual and society than the drug itself. Criminalising users to deter them and others is the central plank of the current legislation that makes cannabis a Class B drug and the explicit reason why it was regraded up to Class B last year. This damages users who are caught in possession as it limits their career opportunities and is particularly hurtful to those using for medicinal reasons. It also costs the public purse large amounts through police and court time and prison costs - which was one reason why cannabis was downgraded to Class C in the first place!

2. Distorts markets to greater harm to society
When precaution results in a variety of different drugs being made illegal then markets and competition between them develop. There are incentives for drug dealers to sell the most profitable, most addictive and least likely to be detected drugs. This pushes the market in the direction of drugs such as heroin and crack which use small volumes and have no odour and away from cannabis which is bulkier and smelly. The harms of the former are much greater than those of cannabis yet the penalties for possession and supply are similar [7-v-5 years and life-v- 14 years respectively].  There are examples of young people initiating illegal drug use with heroin rather than cannabis simply because cannabis is harder to get hold of and deaths have been the result.
3. Impossibility to refute
When the precautionary principle is used to deal with a concern for health effects of drugs, such concerns can never by fully allayed since any drug can be associated with harms of some sort if widely enough used. There is therefore always justification for maintaining precautions and keeping drugs illegal. This was the basis of the last government’s decision to keep ecstasy Class A even though the evidence of harm was clearly much less than with other Class A drugs such as heroin and crack. Although the immediate harms were not as severe as Class A drugs, the Home Secretary said that there were concerns about the long-term effects so it would consequently not be downgraded.  Not much consolation to the many people in prison for up to 5 years for possession of ecstasy for personal use – an unlikely and unknown long-term possible health consequence is given as justification for an immediate destruction of liberty and livelihood.

4. Disproportionate penalities
The precautionary principle also fails to take into account the proportionate risks from drugs and the absolute level of risk that should be required to ban a drug. I have argued that some metric of harm developed in reference to other harmful behaviours e.g. horse riding, rock climbing or sun-tanning should be invoked as a threshold of risk to decide if any drug should be made illegal. Some argue that as illegal drugs have no value then there are no dis-benefits of banning them. The flaw in this argument vis a vis criminalisation has been made in Point 1.

5. Entrenchment of a flawed institutionalised moral position on drugs
Precaution is often either overtly or subconsciously based on the argument there are no benefits to the use of the drug so that it should therefore be made illegal.  This argument reflects a biased and entrenched institutional position that the establishment and law makers alone understand costs and benefits and that drug users are all dependent, addicted losers. In fact, most people who use illegal drugs do so because they want to, NOT because they are addicted. For those for whom illegal drug use is a choice, benefits include relaxation, dancing, mind expansion etc;  these are real benefits/motivators that should not be ignored by legislators

6. Encourages other drug use
The most costly and perverse consequence of the precautionary principle is that it encourages the use of legal drugs which are more harmful than the ones being banned. It can be argued that the epidemic of alcohol-related health harms that the UK is experiencing now is partly driven by people who might use drugs that are safer than alcohol, such as cannabis and ecstasy, being deterred by the risks of criminalisation and/or misinformation about the relative harms of these drugs, so are driven to drinking instead. It is seriously questionable whether there is any health justification for criminalising the use of drugs that are safer than alcohol. Punishing drug users - but not drinkers or tobacco smokers - to protect them and society from health harms is ineffective, uneconomic, morally indefensible and patently unjust. The growing use of cannabis in retired people in the USA when they no longer have to fear workplace drug-testing reflects the true deterrent effects of the law to limit free choice.

7. Blocks new drug discovery
The precautionary principle also limits the development of new drugs that might be safer than alcohol – such as alcohol alternatives – which would be subject to a much higher level of safety than alcohol itself.

8. Denies innovation and medical progress
Some drugs, particularly LSD, MDMA and psilocybin, were showing promise as therapeutic agents before they were made illegal. This research then stopped as a consequence and only now, 40 years on is being resurrected with very promising findings. The recent banning of mephedrone means that new antidepressants and other treatments e.g. for obesity and narcolepsy that might have emerged from that chemical series will now not happen. It is not that such drugs would necessarily be illegal but the regulatory and legal complexities of working in this chemical arena and the possibility that new drugs might be outlawed if legislation changes in the future provides too big a disincentive to the pharmaceutical industry. 

Drugs present a variety of dangers to those that take them – however, using the precautionary principle as the basis for prohibition risks creating unnecessary harms without properly protecting users. If we are going to have a coherent and effective strategy to tackle the problems that drugs cause, removing the harms caused by the precautionary principle must be a priority.

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