Reefer madness

Drugs Without the Hot Air: Minimising the Harms of Legal and Illegal Drugs. By David Nutt. UIT Cambridge; 352 pages; £12.99. To be published in America in September; $19.95. Buy from Amazon.com, Amazon.co.uk

FOR a few months in 2009, David Nutt was the most famous pharmacologist in Britain. As chairman of the Advisory Council on the Misuse of Drugs (ACMD), he was responsible for advising the government on the relative dangers posed by different kinds of illegal substances. He published a scientific paper that landed him in hot water, when he compared the risks of taking Ecstasy with those posed by horse-riding, and found riding to be several times riskier.

He was publicly rebuked, on the spurious grounds that the two activities are not comparable, by Jacqui Smith, the home secretary at the time. The following year he contributed to a paper that came to the conclusion that alcohol was a more harmful substance than cannabis, LSD or Ecstasy. Alan Johnson, Ms Smith’s successor, responded by removing Professor Nutt from the committee.

Theoretically, Britain’s drug rules focus on the idea of harm reduction, with illegal drugs classified into one of three categories depending on how dangerous they are to their users, and to society as a whole. In practice, though, few politicians are able to resist the bid for popularity that comes from running a scaremongering moral crusade. It is this hypocrisy—and, perhaps, a little hurt pride—that has inspired Professor Nutt to write his book.

The professor wants Britain—which, prior to the 1970s, had drug policies that would seem impossibly liberal today—to honour the spirit of its laws, and to adopt a more sober analysis of the risks posed by individual drugs before deciding whether or not to ban them. He argues that government pronouncements on the dangers of illegal drugs are hysterical and exaggerated, and therefore damaging to its credibility. And, since prohibition has failed everywhere it has been tried, he wants to lay out the evidence for the harms (and benefits) that different drugs can provide, so that users can weigh these up in their own minds.

The book’s title is a nod to “Sustainable Energy Without the Hot Air”, a recent minor classic by a Cambridge don, David MacKay. Armed only with the laws of physics, reams of publicly available information, a little maths and much wit, Mr MacKay attempted to dispel the fog and special pleading surrounding renewable energy. His aim was to demonstrate exactly how much power Britain could hope to gain from wind farms, solar panels, nuclear reactors and the like.

Professor Nutt clearly wants to do something similar for drugs, reminding readers that, like the legal sort, illegal drugs offer a mix of benefits and harms. He presents data from pharmacological or epidemiological studies on what exactly those are, bolstering his argument with discussions on the nature of addiction and changing attitudes to psychoactive substances throughout history.

For relatively well-understood drugs such as alcohol or cannabis, there is plenty of data to analyse and Professor Nutt’s approach works well. His conclusion that alcohol is one of the most harmful drugs available may surprise some, but it is backed up with solid evidence, as are the discussions of the comparative safety of hallucinogens such as LSD. But scientific rigour is not always possible. New drugs appear with bewildering frequency; combine that with the official instinct to clamp down without waiting to see how harmful a substance truly is, and high-quality evidence is often hard to come by. Prohibition muddies the waters further. Although drugs such as cannabis are pharmacologically less harmful than alcohol, the fact that they are illegal means that being caught with them poses a particular risk.

An anecdote about mephedrone, a synthetic derivative of a compound found in kat, a stimulant drug popular in parts of east Africa, illustrates the problem. A couple of untrue stories in a British tabloid newspaper sparked a full-blown panic about the dangers of the drug. Political pressure for a ban soon became irresistible, even though the ACMD had virtually no evidence at all about the pharmacological properties of the drug itself.

Regardless of such gaps in the evidence, Professor Nutt’s rational, cool-headed approach is surely the right one, even if some of his throwaway remarks, for instance in the chapter on alcohol, or about the alleged problem of video-game addiction, do not sit well with the generally cautious tone of the book. Those are minor blemishes in an otherwise refreshingly clear-eyed work. Anyone looking for a calm and objective overview of the drugs available in Britain would do much better to read Professor Nutt’s book than to believe what they read in the papers, or what they hear from the lips of government ministers.