Cannabis: the evil weed?

Horizon last night did a reasonably balanced program looking at the various claims for and against cannabis, the world's most popular illicit drug. You can watch it again on iPlayer if you missed it.

They looked into its history - that it is likely that it has been used by humans for around 3,000 years at least. Into claims that it is a "gateway drug" that encouraged users to move onto harder drugs which showed in trials with rats that this was unlikely. And into claims that it damaged young brains which in trials with mice seemed to suggest that it did indeed create long term memory degradation when given to/used by young adolescents (defined as below around 15 years of age).

They also seemed to be confirming that, assuming one's brain was properly developed before using cannabis regularly, the potential longer term side effects are nonetheless relatively rare.

They looked into some of the claims made for its medicinal properties, talking to a doctor in California who, under their medical marijuana rules seems to prescribe it for all sorts of things from chronic pain to slight anxiety or even, as the presenter suggested, "writers block". And in the one UK licensed pharmaceutical grade production facility was astonished to find that many strains also contain an anti-psychotic substance (which to me reinforced the idea that somehow people in danger of developing mental illnesses may actively seek it out as self-medication).

So, what does it all suggest about the predominant public policy of prohibition? The presenter, "addiction specialist Dr John Marsden" (he looks after patients with addictions to "harder" drugs like cocaine and heroin), concluded the program by saying that the real "problem" with cannabis was the waste of potential it causes - presumably he felt, as an addiction specialist, that all the other [possible problems are relatively low risk enough to make a blanket policy unwarranted.

But even here I think he's quite wrong to infer that such a "waste" of potential is good enough reason for legal prohibition - after all, one user's "waste" of life "sitting around smoking dope all day and doing nothing useful" as Marsden put it I think, is another user's occasional recreation. Set aside any debate as to whether George Washington managed to found the greatest nation on earth whilst toking on the stuff! Exactly the same claims could be made of alcohol, and the evidence is available in far greater numbers - that it can cause psychoses, all sorts of physical and mental illnesses, sitting around drinking all day is a waste of potential, it can also have medicinal benefits. Yet Churchill won the war on the stuff!

Yet we license one for sale and prohibit the other with criminal sanctions that themselves do as much to destroy lives as the substance itself (witness in the USA the scheme where anyone convicted of a possession charge would be denied university funding for example). We know that prohibition drives the supply into the hands of criminal gangs who have no compunction about selling it to those even proponents of legalization would want to protect - the youngsters whose developmental processes can be damaged by access to it too young - and further whose business model tends to encourage them to try to sell other, potentially more dangerous drugs, to their existing customers to maximize profits. We have seen how, after downgrading, the consumption in this country actually dropped. It will be interesting to see whether the uprating to category B will increase consumption again and thus prove utterly counter productive.

As with alcohol, a legalized weed, as shown in the images of medical marijuana dispensaries in California, and also the cafe culture in the Netherlands and the more free attitude in Switzerland, would give people more choice about methods of taking the drug - reducing, probably, the predominance of smoking it (it is at its most potentially harmful when smoked with tobacco). And it would increase awareness of the different strengths and their effects as decent shops would sell a range, rather than, at present, having to take what you can get wherever you can get it.

The law, as usual with drugs laws, is counter-productive. The resultant criminal culture surrounding it makes society less safe not more. It is not based on the evidence. It is not consistent with attitudes to other drugs such as alcohol where even the drunk is more capable it seems of exercising their own judgement most of the time and is also freer to get help because it is legal and not so much of a taboo subject. The recent reclassification defies belief frankly and is simply another reason to oppose all government interference in our lives as ill informed and nannying.

Our legislators should be ashamed of themselves.