If you complied a list of all the people you wouldn’t offer a column on drugs policy to then Ann Widdecombe would surely be in the top ten and not too far away from Melanie Phillips, but no, in its infinite wisdom the Guardian has handed Widdie the opportunity to drivel forth on a subject she patently knows nothing about, thus proving the adage that ‘scientific advisors advise, politicians talk out of their arse’.

Still, as it gives me a perfect opportunity to take about some real science, why waste it…

So let’s start with Widdie’s second paragraph, in which she utterly destroys her credibility before she’s even managed to put forward an argument:

From all the uproar, you would think science was united around a fixed view that drugs are harmless – whereas there is no such universality of opinion, and the government’s own Advisory Council on the Misuse of Drugs is not united either.

Hardly. If you searched PubMed for every single reference to cannabis, let alone to any other controlled narcotic, I can guarantee that you would not find a single scientist arguing that drugs are harmless. They’re not, and we all know it, hence that is NOT what this current debate is about.

What it is about is the efforts of scientists who, as members of  government advisory council, have been attempting to produce a coherent, scientifically informed, framework for the UK’s system of classifying controlled substances based on something that we know exists – evidence of the relative levels of risk and harm associated with each controlled drug – instead of something that we know to be utterly worthless – the presumption that the UK’s existing, prohibitionist, drug laws serve as a deterrent and dissuade people from taking drugs.

We know that, and so do some parliamentarians:

78… Steve Rolles, information officer for Transform, also told us: “there is no research at all—not a single piece of research ever done by the Home Office that I am aware of—into the effectiveness of the classification system as a deterrent and the independent research that we do have—what little there is—suggests that at best it is a marginal impact on drug taking decisions”. The Home Office Minister Vernon Coaker was unable to provide us with any specific evidence to the contrary.

79. In oral evidence, Professor David Nutt, Chairman of the ACMD Technical Committee also said: “I think the evidence base for classification producing a deterrent is not strong”, while Andy Hayman, Chair of the ACPO Drugs Committee, told us: “I cannot envisage any user – a dependent user, that is – having any kind of thought as to whether it was a Class A, B or C drug they were consuming”…

80. The penalties associated with classification can have serious consequences for users in terms of sentencing. As noted above, the classification system also plays a significant role in directing expenditure of the £1.5 billion that the Government spends annually on tackling drugs. We have found no solid evidence to support the existence of a deterrent effect, despite the fact that it appears to underpin the Government’s policy on classification. In view of the importance of drugs policy and the amount spent on enforcing the penalties associated with the classification system, it is highly unsatisfactory that there is so little knowledge about the system’s effectiveness.

In the next two paragraphs of the report, the Committee went on to demolish the other key proposition that prohibitionists cling rigidly too, the suggest that the current classification system sends out ‘signals’ to drug users and to wider society:

81. The lack of evidence of a deterrent effect is particularly significant in view of the Government’s eagerness to use the classification system to ‘send out signals’. As Lesley King-Lewis, Chief Executive of Action on Addiction, pointed out: “We do not even know if the public see that if a drug is in Class A is that more of a deterrent or is it actually an attraction?”. Nevertheless, the then Home Secretary cited as justification for the review of the classification system announced in January 2006 the fact that “Decisions on classification often address different or conflicting purposes, and too often send strong but confusing signals to users and others about the harms and consequences of using a particular drug”. Home Office Minister Vernon Coaker also insisted that although the purpose of classification was to “categorise drugs according to harm”, it “does send out messages; it does send out signals to people, in a way which people understand”. Mr Coaker further posed the question: “is not part of any system with respect to drugs […] not only trying to send messages out to people who misuse drugs but also about trying to send messages out to people out there in the community?”

82. Transform Drug Policy Foundation was of the view that “Criminal law is supposed to prevent crime, not ‘send out’ public health messages” and warned that it could backfire by “fostering distrust of police and public health messages amongst young people”. We are inclined to agree. The Government’s desire to use the Class of a particular drug to send out a signal to potential users or dealers does not sit comfortably with the claim that the primary objective of the classification system is to categorise drugs according to the comparative harm associated with their misuse. It is also incompatible with the Government’s stated commitment to evidence based policy making since it has never undertaken research to establish the relationship between the Class of a drug and the signal sent out and there is, therefore, no evidence base on which to draw in making these policy decisions.

There is no supporting evidence for the Home Office’s bogus criminal justice-led approach to tackling drug use. Not a jot.

Not that that is going to deter Widdie from bullshitting:

Drugs account for about a third of all crime and around 80% of all acquisitive crime (theft).

Well, yes, criminalising drug users does bump up the crime statistics and drug users do commit acquisitive crimes in order to facilitate their habit…

…and there is still no evidence whatsoever to support the idea that the present classification system has any deterrent effect whatsoever – the prevalence of cannabis use amongst young people actually fell during the period that its reclassified downwards to a Class C drug.

Moreover, and even though reliable data is understandably difficult to come by, sending drug users to prision will typically have little or no impact at all on the primary cause of the criminal behaviour, their drug habit. In its most recent report on drug use in prison, the European Monitoring Centre for Drugs and Drug Addiction found that around 37% of prisoners had taken drugs while in prison, with 0.3% having injected heroin.

We’ve been banging up drug users for years, using penalties attached to the current classification system, and there is no evidence to show that this has any impact at all on the level of drug-related crime. What those of us who argue for decriminalisation of drug use contend is that treating drug use as a public health concern rather than a criminal justice issue creates far more scope for tacking the causes of drug-related crime, particularly in terms of making it easier to get habitual drug users into either effective treatment and rehabilitation programmes or into managing their habit without resorting to crime to facilitate it.

That last option was the underlying premise of the policy of ‘policing and prescribing’ that operated until the late 60’s/early 70’s in relation to the use of heroin, a period during which there was no black market in heroin to speak off and, at most, around 2,000 ‘managed’ heroin users in the UK , rather than the 200,000 plus chaotic users we have today.

It’s a feature of prohibitionist rhetoric that they constantly bang on about the statistics for drug-related crime without ever daring to admit that prohibition has utterly failed to address this particular problem or that they haven’t the first idea what to do about it.

They are present in about 20% of road traffic accidents.

Bulllll-shit!

There are no reliable statistics on the prevalence of drug use in individuals involved in road traffic accidents because the government don’t collect any data on the subject:

We do not collect statistics specifically for drug driving offences, because the records relate to impairment due to drink or drugs and the two are not distinguished. It is also common practice not to pursue enquiries about drug impairment in cases where both drugs and alcohol are suspected, because it is much simpler to prove the same offence from evidence linked to alcohol. So, published Ministry of Justice figures on motoring convictions, and the Department’s casualty statistics, are not reliable indicators of drug use by drivers, or the involvement of drugs in casualty accidents.

However, the same consultation document (dated Feb 2009) goes on to add that:

5.8 Between 1985 and 1987 the Transport Research Laboratory carried out a study published in 1989 to measure the incidence of drugs that impair in fatal road accident casualties (not just drivers). This showed that the incidence of prescription drugs and illegal drugs was relatively low in comparison to alcohol – a ratio of about 1:5.

5.9 A further similar study was published in 2001, using a sample of 1,184 fatalities, including 533 drivers and 246 riders. Results from this study show that at least one impairing prescription or illegal drug was detected in 22.9 per cent of the drivers in the sample and 20.3 per cent of the riders. These figures are not much lower than the proportion (24.1 per cent) in the total sample of road users, including passengers and pedestrians. Alcohol was present in 31.5 per cent of the overall sample, although quantities were not measured. The incidence of such drugs had increased by about three times since the previous study. Also, 17.7 per cent of the drivers and 13.4 per cent of riders tested positive for a single drug, with 5.6 per cent of drivers and 6.9 per cent of riders tested positive for multiple drug presence – a material increase from the previous survey.

So the drug-alcohol use ratio appears to have shifted over a 12-15 year period from 1:5 to around 2:3, which is significant in itself  but, it also has to be noted both that this data is taken from fatalities, not from all RTAs, and that we’re not just taking about drugs controlled under the Misuse of Drugs Act hence, ‘at least one impairing prescription or illegal drug was detected’, with benzodiazepines proving popular amongst the multiple drug users, although it appears that cannabis was the main drug of choice in just over half these cases.

Does all that add up to drugs being present in “about 20% of road traffic accidents”?

No, of course it doesn’t.

For starters, at most only 1.6% of all RTAs result in a fatalities – and that figure assumes one fatality per accident, which is obviously unrealistic. The true figure will be lower, once accidents resulting in multiple fatalities are taken into account although maybe not be too much, so anything from 1.3-1.4% is probably in the right ballpark. What this tell us is that what we have is small, unrepresentative data set drawn from a sample of only the most serious accidents, one that is unlikely to give up a reliable estimate of the prevalence of drug use in RTAs as a whole.

Fortunately, given the data we have to hand, the Department of Transport’s statistics provide a much better basis for such an estimate, which is to be found in table 39 of its Annual Report on Road Casualties, and that’s the data on the numbers of breathalyser tests administered to, and failed by, drivers and motorcyclists involved in road traffic accidents.

From that table we find that of the 318,000 drivers/riders involved in a recorded RTA in 2007, just over 179,500 were breathalysed, giving us a sample to work with of 56.5% – now we’re cooking.

Of those 179,500, a total of 6.728 either failed the test or refused to take it, so that’s 1.97% of our drivers/riders who were under the influence of either alcohol, drugs or both at the time they had an accident and we have a 3:2 ratio of alcohol to drugs (ignoring any overlap for simplicity’s sake) which gives us 2691 drug users (0.79%) of the total. Finally we need to adjust that figure to give an estimate of the number of accidents as opposed to the number of drivers/riders involved in those accidents, and with 182000 recorded accidents for the year that gives us an estimated 819 accidents involving drug users, 0.45% of the total…

…and Widdie’s out by a factor of just over 44.

That’s the good news – the bad news is, if we go back to the data on fatalities, those 819 accidents are likely to result in 378 fatalities. That’s  nine people on a mortuary slab for every 20 prangs with a stoner at the controls, which is not good odds at all.

And that is how you use statistics to construct a solid public health argument.

Although only 1 road accident in every 227 involves an individual driving/riding under the influence of drug, 9 out of every 20 of those accidents will result in a fatality.

That doesn’t tell us that drugs are universally bad thing, which is what Widdie wants, but it does tell us that driving while stoned is a very bad idea, so make sure you stock up on munchies well in advance because that run down to the all-night garage could be a killer.

People have died as a result of taking ecstasy and committed crimes under the influence of cannabis.

Yes, we know – people die of all manner of things every year, including lots of things we don’t prohibit and a hell of a lot of stuff over which we have little or no effective control. What matters in terms of formulating public policy the scale of the risks involved in a particular activity, and their associated social costs, when set against the social costs of prohibition.

The mortality rate amongst ecstasy users is, of course, the issue on which Professor David Nutt most ruffled a few politician’s feathers by comparing the risk to that of horse-riding – and if that analogy pissed so many people off then where I’m going next is sure to get the hate mail flying.

Let’s start by quantifying the risk of dying as a result of taking ecstasy, where the generally accepted figure is an average 30 deaths a year and its also been estimated that around 730,000 people drop E’s every year – all told that’s a base risk of death of 1 in 25,000 per year.

Now let’s look at a couple of things where the same 1 in 25,000 risk per year also arises, starting with…

Breast Cancer… yes, if you’re a woman and you’re aged between 20 and 29 then your annual risk of developing breast cancer is 1 in 25,000.

Now that’s not such a good analogy because breast cancer is something over which we have no real control, so how about something that is controllable, at least in theory.

Pregnancy… yes, the annual risk of a woman dying as a result of complications arising during pregnancy/childbirth in the UK, today, is 1 in 25,000.

So, if we follow Widdie’s ‘logic’ that a 1 in 25,000 risk of death is to great a risk to be allowed then it follows that the government should ban procreation on the grounds that the risks involved are, statistically, identical to those involved in taking ecstasy.

Funnily enough, I don’t think banning pregnancy is a viable policy option for any government

This so-called soft drug also produces psychosis.

If you ask me, so does becoming a Conservative MP but in truth I’ve not no more reliable evidence for that causal link than drug researchers have for a causal link between cannabis use and long-term psychosis.

Without going through all the rigmarole of digging out the research papers, the current state of play is that we’re still some considerable way short of understanding the neurological and biochemical mechanisms that underpin psychotic conditions, such as schizophrenia, but we have epidemiological data which suggests an elevated risk of psychotic illness in chronic cannabis users linked to a possible pre-existing genetic susceptibility to such conditions.

So far as quantifying that risk goes, the overall risk of developing a psychotic illness in the general population is around 1 in 100 – from which we can project 6-7 psychotic MPs, feel free to make your own list – while amongst chronic stoners the risk appears to increase to around 1.4-1.6 in 100.

The moral of this story is don’t toke if you come from a family history of mental illness, particularly a history of psychotic disorders, otherwise you should be fine to carry on watching Cheech and Chong.

Are we finished yet? Err no, there’s still one old chestnut to go…

For some, it is but the gateway to hard drugs and death. Indeed, some studies in Amsterdam, where soft drug use is lawful under certain circumstances, suggest that when soft drug use increases, so does hard drug use.

Again, the whole ‘gateway drug’ thing was dealt with several years ago. In 1999, a study by the Division of Neuroscience and Behavioral Health at the Institute of Medicine, “Marijuana and Medicine: Assessing the Science Base“, failed to find any evidence to support a link between cannabis use and the subsequent abuse of other drugs.

In 2002 researchers from the Rand Drug Policy Centre developed a mathematical model using data from the US National Household Survey on Drug Use/Abuse which demonstrated that any gateway effect associated with cannabis use is likely to be a function of prohibition and not down to the common myth that using one drug leads inexorably to another:

The results of the DPRC model of drug initiation do not disprove the gateway effect; they merely show that another explanation is plausible. In fact, the researchers note that something like a gateway effect probably does exist, if only because marijuana purchases bring users into contact with a black market that increases access to hard drugs.

However, it is possible that any true marijuana gateway effects can explain only a tiny fraction of individuals’ risk of hard drug use in comparison with the risk attributable to their propensities to use drugs. Moreover, it is possible that marijuana use could increase the risk of hard drug use for some youths while decreasing that risk for others, thus resulting in an insignificant effect from marijuana use on drug use when looking at the entire population of adolescents.

The researchers don’t advocate the legalisation, or even decriminalisation of cannabis, what the do argue is that those developing public policy should weigh the costs of prohibition against the impact of cannabis use when formulating policy responses, which is not materially different to the position taken by Professor Nutt and roundly ignored by both the government and, now, by Ann Widdecombe.

More recently a study by researchers at the University of Pittsburgh, published in December 2006, also failed to find evidence to support the gateway hypothesis.

Currently, the only study to seemingly support the gateway hypothesis, other than speculative animal studies, is the Victorian Adolescent Health Study, which I’ve yet to look at in detail but which, on a cursory look, appears to provide nothing by way of evidence that couldn’t plausibly be accounted for by Rand’s model of drug use.

That is not exactly a litany of reassurance.

You don’t say, Ann…

Who would be reassured by such a litany of poorly constructed and misconceived prejudices masquerading as an argument or by her evident lack of understanding of her own ‘evidence’ let alone that on which the ACMD recommendations on the classification of cannabis and ecstasy were based.