From last weeks BMJ (British Medical Journal)
"The government’s decisions compromise its commitment to evidence based policy
In the United Kingdom medicinal drugs and treatments are regulated through the 1968 Medicines Act and illegal drugs through the 1971 Misuse of Drugs Act. The Misuse of Drugs Act defines controlled substances on the basis of their potential harm, taking no account of benefits that users might claim. The distinction between medicines and illicit drugs is, of course, not sharp, and many valuable medicines (including Ritalin, GBH ( hydroxybutyrate), tranquillisers, and analgesics) turn into dangerous killers when they escape on to the streets.
The Misuse of Drugs Act established the Advisory Council on the Misuse of Drugs (ACMD) "to keep under review the situation in the United Kingdom with respect to drugs which are being or appear to them likely to be misused and of which the misuse is having or appears to them capable of having harmful effects sufficient to constitute a social problem." The council currently has 33 appointed and co-opted members, with expertise in pharmacology, psychiatry, public health, drug charities, schools, mental health, and forensics. On the basis of extensive reviews and consultations, these experts advise the government on which drugs should be controlled and on their classification as A, B, or C, according to the burden of harm.
Several drugs have been added to the controlled list in the past few years. Professor David Nutt, the present chairman of the council, led a review of ketamine that resulted in its classification (class C) in 2006.
According to the Misuse of Drugs Act, classification has only one function—to guide sentencing for possession and dealing in drugs. However, it has been hijacked for political slogans, banner headlines, policing targets, and educational messages. In 2006, the Commons Science and Technology Committee concluded that the current classification system was not fit for purpose.
The Academy of Medical Sciences, the Royal Society of Arts,and the UK Drug Policy Commission have all argued for a reappraisal of drug classification. That need is highlighted by the outcome of a recent study of a comprehensive quantitative matrix of harm that avoids arbitrary divisions between classes A, B, and C.The results were startling: alcohol, tobacco, and solvents (included to provide familiar yardsticks) were ranked as more harmful than many controlled drugs; the class A drug ecstasy (MDMA) had the lowest harm rating among all the controlled drugs analysed; and the overall ranking of drugs did not even statistically correlate with the A, B, C classification (figure).
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Mean harm scores for 20 substances. Reproduced, with permission, from the article by Nutt et al
The growing concern about classification has been amplified by the government’s rejection of two recommendations of the ACMD—that cannabis should remain class C and, very recently, that ecstasy should be downgraded from A to B. Ministers even announced the decisions in advance of the ACMD reports.
In refusing to downgrade ecstasy, the government said, "We do not dispute the ACMD’s scientific findings on the harms of ecstasy based on current evidence" but "the government will not send a signal to young people and the public in general that we take ecstasy less seriously. . . We are concerned that its downgrading could lead to an adverse impact on patterns of use and attitudes."
However, the Science and Technology Committee criticised "the government’s proclivity for using the classification system as a means of ‘sending out signals’ to potential users and society at large—it is at odds with the stated objective of classifying drugs on the basis of harm . . . We have found no convincing evidence for the deterrent effect, which is widely seen as underpinning the government’s classification policy."
Indeed, according to the British Crime Survey 2007-8,use of class B and C drugs has decreased since 1996, whereas, paradoxically, use of class A drugs has remained fairly stable. And the substantial decline in cannabis use since 2000, if anything, accelerated when cannabis was downgraded from B to C in 2004.
Professor Nutt has been the focus of particular pressure. In a peer reviewed article, published in January this year in his academic capacity, he argued that the definable risks of ecstasy use (particularly morbidity and mortality) do not exceed those of recreational horse riding.This article drew attention to the disparity between risk assessment and risk perception, but he was pilloried in parts of the media for suggesting that an illegal activity can be compared with a respectable pastime. And on 9 February, during his afternoon clinic, Professor Nutt received a telephone call from the home secretary, demanding an apology for the offence caused to the parents of victims of ecstasy.
There is wide acceptance in government and the media that illegal drugs are somehow different from other areas of public risk and that this justifies disregarding expert opinion about their harm. But the rationale is never articulated. Why is government not concerned about the message that crack cocaine and heroin are essentially similar to ecstasy in their harm, and that the government knows better than its own experts?
The rejection of the ACMD’s advice is a challenge not only to the working of the Misuse of Drugs Act but also to the government’s commitment to evidence based policy. It is no surprise that the decision on cannabis was criticised by two former government chief scientists.
In many member states of the European Union, the law does not differentiate between illegal drugs on the basis of harm; this allows judicial authorities to consider the nature of the drug offence when sentencing. But evidence about all the harms that a drug can cause (from acute and chronic effects on the user to the effect on families and society) is important for many aspects of policy, such as policing and sentencing, education, public health, and the provision of medical and social care. Can’t the scientific ranking of drug harms be decoupled from political decisions related to policies? It should be left to the experts, outside the glare of the political spotlight, to provide the best current information on each area of harm and devise ways of weighting and collating those indices of harm to inform each area of policy.
Colin Blakemore, professor of neuroscience