It is incongruous, incoherent and out of date; unwieldy and peppered with anomalies, an agglomeration of miscellaneous provisions adopted to address situations that in many cases no longer apply. The law governing illegal drugs should be scrapped almost in its entirety.

Don’t take it from me: this is what the Metropolitan Police assistant commissioner John Yates, one of the Met’s most senior officers (and the one with the interminable inquiry into cash-for-honours), has to say about the Misuse of Drugs Act 1971 and its offshoots. “The law as it stands is incoherent and out of date. It is based far more on prejudice and folk myth than on reason. It makes no mention of the UK’s two most death-dealing drugs: alcohol and tobacco . . . It criminalises people who are not otherwise criminals.”

He and his fellow members on the Royal Society of Arts commission on illegal drugs are not exactly dangerous hip-swinging liberals. There is Mr Yates, and the Professor of Government Anthony King, an MP, an MSP, the home affairs editor of The Daily Telegraph and the president of London First, the business leaders’ group, as well as a string of drug, health and social workers. Two years they have spent examining whether drugs policy in Britain works or not. And yesterday they announced the same conclusion secretly reached by the Prime Minister’s strategy unit four years ago: it has failed.

I’m not sure why it took them two years to work that out, but there we are. When the Misuse of Drugs Act was framed, amid national concern about the overprescription of heroin by GPs and a moral panic over cannabis, drug use was much lower than it is now. The number of problem users was in the low thousands, compared to the quarter-million there are today. If the aim of the Act was to deter the use and supply of proscribed or controlled drugs, it has clearly failed, as the commission unequivocally concludes.

Drugs are not going to go away, the report says, and hoping that they will is hallucination: “People have used them for thousands of years, widespread demand exists, supply is plentiful, and the illegal drugs industry, not to mention the alcohol, tobacco and legal drugs industries, are among the best organised and most market-oriented in the world. Prohibition is no more a viable policy in Britain today than it proved to be in America during the 1920s and 1930s . . . Policy and the administration of policy should be based on a cool appraisal of the facts, not on fantasy and wishful thinking.”

If drugs cannot be eradicated, they conclude, “then the principal object of public policy should be to reduce as far as is humanly possible the great harms that they may cause”. And this is where we get into the meat of the report. What the commission proposes is that society stop looking at drugs in terms of their criminality — how much criminal behaviour does each one represent in its little classification of A or B or C — and examine instead the harm that each drug causes, to the person taking it, to others around them and to society. Heroin, for instance, has a high social cost in terms of shoplifting and burglary as well as a high health risk; cannabis represents a much lower threat. So far so ABC.

But the proposed “harms index” that the commission would like to see developed would be more complex than ABC. If, for instance, it included those most commonly used drugs, alcohol and tobacco, alcohol — surprise, surprise — would come as high up the harms index as ketamine, and higher than banned amphetamines. Without quite specifying any drug that should be legalised, the commission recommends that criminal sanctions be confined to “those offences connected with drugs that cause the most harm”. I assume this means that selling cannabis to six-year-olds would land you in jail, while taking an Ecstasy pill in a nightclub might be allowed.

Here the commission runs into a problem: the complicated system of reclassification and reconsideration would imply greater regulation of alcohol and tobacco. And their nerve deserts them: “The commission does not recommend that alcohol and tobacco should be regulated as strictly as their objective harmfulness might seem to indicate . . . Alcohol and tobacco would have to be specifically exempted from consideration under many of the offences listed in the schedule.” Why? If you reclassify drugs according to harm, and ask society to reconsider its entire attitude to them, there is no good argument for excluding some of the most damaging. Part of the reason why drug laws are so disrespected and so widely flouted is that teenagers recognise that the lower classified drugs do far less harm to people around them than alcohol or tobacco. You either accept that society deems certain drugs to be morally wrong, or you take a pragmatic harm-based approach, with no opt-outs.

It seems that politicians in today’s climate will always retreat to the comfort zone of moral certainty which simply says that drugs are “bad”; the commission knew before the report was published that the Government intended to ignore it and insist that its own approach is working. That has been to fiddle with classifications — cannabis from B to C, methamphetamines from B to A — and expand the circumstances in which someone may be forced to take a drug test (on arrest, even before any charge) or attend a treatment course. Yet the commission points out that this forces some people into treatment who do not need or are not ready for it, while preventing others who want treatment from seeking it for lack of places or fear of incrimination.

Wishing the problem away isn’t working. I wonder which frontline politician will be brave enough to admit that it’s not as easy as ABC. It never was.

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