In short the current UK classification system has no real scientific ground, almost harmless drugs are classified as hard drugs but almost have no harm and very harmful drugs like alcohol and tobacco that have great impact on us all are legal.
Two ways to solve this, make drinking a beer and smoking a cigarette illegal (as the US tried with great success in the '20) or make it legal to use Cannabis and all other less harmful drugs.
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Discussion
The results of this study do not provide justification for the sharp A, B, or C divisions of the current classifications in the UK Misuse of Drugs Act. Distinct categorisation is, of course, convenient for setting of priorities for policing, education, and social support, as well as to determine sentencing for possession or dealing. But neither the rank ordering of drugs nor their segregation into groups in the Misuse of Drugs Act classification is supported by the more complete assessment of harm described here. Sharply defined categories in any ranking system are essentially arbitrary unless there are obvious discontinuities in the full set of scores. Figure 1 shows only a hint of such a transition in the spectrum of harm, in the small step in the very middle of the distribution, between buprenorphine and cannabis. Interestingly, alcohol and tobacco are both in the top ten, higher-harm group. There is a rapidly accelerating harm value from alcohol upwards. So, if a three-category classification were to be retained, one possible interpretation of our findings is that drugs with harm scores equal to that of alcohol and above might be class A, cannabis and those below might be class C, and drugs in between might be class B. In that case, it is salutary to see that alcohol and tobacco—the most widely used unclassified substances—would have harm ratings comparable with class A and B illegal drugs, respectively.
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Our findings raise questions about the validity of the current Misuse of Drugs Act classification, despite the fact that it is nominally based on an assessment of risk to users and society. The discrepancies between our findings and current classifications are especially striking in relation to psychedelic-type drugs. Our results also emphasise that the exclusion of alcohol and tobacco from the Misuse of Drugs Act is, from a scientific perspective, arbitrary. We saw no clear distinction between socially acceptable and illicit substances. The fact that the two most widely used legal drugs lie in the upper half of the ranking of harm is surely important information that should be taken into account in public debate on illegal drug use. Discussions based on a formal assessment of harm rather than on prejudice and assumptions might help society to engage in a more rational debate about the relative risks and harms of drugs.
