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Drug driving consultation 2013

Drug science hexagons

Below is DrugScience’s response to the Government’s drug driving consultation. The consultation has now closed. Parliament will not be debating these changes in full as despite their serious nature, they are to be instituted through an amendment of the Road Traffic Act 1988 (secondary legislation).

Do you agree with the Government’s proposed approach as set out in policy option 1? If not please provide your reason(s).

No. DrugScience recognises the need for a change in the law to increase the ability of police to prosecute those impaired by drugs whilst driving. We agree with the need for a strict-liability offence for drug-driving, as recommended by the North Review and the Expert Panel report.

We think that in producing the new Regulations in the Road Traffic Act, the Government has an opportunity to correct an existing shortcoming in the law, whereby a driver impaired by illegal drugs such as cannabis are less likely to be successfully prosecuted than an equally impaired drunk driver. Policy Option 2 would bring about parity between the policy response to drunk drivers and the response to stoned or otherwise intoxicated drivers, and reduce harm to road users.

It is regrettable therefore that the Government’s chosen approach, Option 1, is to establish a new disparity in the law, where the detection of eight particular controlled drugs in a driver’s body may lead to prosecution even when the driver is not likely to be impaired, whilst for alcohol and some other controlled drugs which are no less dangerous when driving, a rational risk-based approach will be used. This rejection of a purely risk-based approach in favour of an inconsistent values-based approach does not appear to be a legitimate use of the Road Traffic Act.

In comparison to Option 2, Option 1 has additional criminalisation costs without any additional benefits in ability to prosecute people who are driving whilst impaired. Option 1 is purportedly favoured by Government to avoid giving “mixed-messages”, but of the three policy options, Option 1 appears to give the most “mixed messages”:

  • Option 2 takes a consistent risk-based approach derived from evidence about the drugs.

  • Option 3, which neither DrugScience nor Government favour, takes a consistent ‘zero-tolerance’ approach (barring alcohol).

  • Option 1 accepts the risk-based approach for some substances which are controlled by the Misuse of Drugs Act but have widespread medical uses (e.g. benzodiazepines, morphine) but takes a zero-tolerance approach to another eight (e.g. cannabis, LSD).

If the Government accepts the experts’ view on some controlled drugs; that specified limits are appropriate as with alcohol, a simultaneous ‘zero tolerance’ approach for 8 controlled drugs is illogical.

Non-medical use of controlled drugs which happen to have widespread medical uses, e.g. benzodiazepines and morphine, for which a risk-based approach is rightly being suggested, is not necessarily any less problematic in terms of road safety or drug harm generally, than the recreational use of those controlled drugs without widespread medical uses, such as MDMA and LSD, for which a zero-tolerance approach is being proposed. Indeed morphine and benzodiazepines are mentioned on many hundreds of death certificates each year, whilst LSD, cannabis, ketamine and MDMA are mentioned on between 0 and 30 or so.

DrugScience notes that by the Government’s own assessment, Policy Option 2 has a net benefit whilst Policy Option 1, their favoured approach, has a net cost. The difference between the two, by its best estimate (which it fairly acknowledges is merely indicative), is £32million of value lost over 10 years by choosing Option 1 over Option 2.

DrugScience recommends that the Government focus on the function and fairness of this road safety legislation, and deprioritise the issue of such “messages” that may or may not be communicated to citizens. The evidence is poor to non-existent that increased toughness or liberality of drug laws communicates ‘messages’ to drug users that affect behaviour.

Option 1 contributes to dangerous “mixed messages” about drugs. The Government’s response to harm caused by Novel Psychoactive Substances has been to promote the accurate message that “just because a drug is legal does not mean it is safe”. However, in Option 1, the Government is proposing a contradictory message; that driving with 8 illicit drugs in the body is more serious than driving with alcohol, or any other legal high in the body. This is confusing, not to mention dangerous.

It is clearly wasteful of resources to choose Option 1 over Option 2. According to the Consultation Document, Option 1 will lead to 3,100 more proceedings than Option 2, which must logically consist of proceedings against people who have been stopped with amounts of illicit drugs in their bodies below the thresholds of impairment set out by the Expert Panel. It is very difficult to imagine a convincing justification for how these prosecutions are in the public interest, if we agree that it would not be in the public interest to begin prosecuting people who drive with alcohol detectable in their blood, but below the existing threshold for alcohol impairment.

Unintended consequences of drug switching DrugScience fears that Option 1 may have unintended consequences which undermine the ability of the policy to improve traffic safety and may cause additional harm. We ask that the Government consider and respond to these.

For every drug in the ‘zero-tolerance’ list, there will be alternative choices, which may be more harmfulInternational evidence suggests that alcohol and cannabis may partly substitute for each other, in that reducing the use of one increases the use of the other. A zero-tolerance approach to cannabis but not alcohol might actually have negative impacts on road safety by promoting drink-driving. This relationship has been observed in America, where the legalisation of medicinal cannabis has been associated with a drop in traffic fatalities.

Effects on Cannabis Users As well as the obvious costs of criminalisation to cannabis users, there may be significant costs to society which the Government has not considered in its consultation document. Most cannabis use is not associated with significant harm. Currently, the police have some power to direct enforcement wisely to where drug use does produce harm, and so typically, police resources are more likely to be directed at dealing with alcohol-related violent crime and disorder over the private use of cannabis by adults. Option 2, which imposes risk-based limits, supports this targeting of harmful drug use in the form of impaired driving. The zero-tolerance approach of Option 1 however amounts to using the excuse of traffic law for blindly trawling for users of the ‘wrong’ drugs.

Deterrent effect? The Consultation document further justifies the Government’s chosen ‘tough’ approach as a ‘deterrent’. There is no good evidence that this is likely to be effective. International evidence fails to show any straightforward link between the toughness of sanctions for illicit drug users and the prevalence of illicit drug use, other factors are much more important. DrugScience particularly notes that this policy will be operating in a wider context in which illicit drug use is already policed through the Misuse of Drugs Act.

LSD The addition of LSD to the list of zero-tolerance drugs is not justified by evidence of what may reduce harm. Instead, it seems to have been added for the “message” only, as an afterthought. LSD is notorious, and certainly is capable of impairing driving, but the Expert Panel notes that there is scant evidence that it is a significant cause of traffic accidents in the UK proportionate to use. The inclusion of LSD but not magic mushrooms which Crime Survey statistics suggest are used at a similar or higher rate in the UK (0.3% of adults vs. 0.2%) and which are comparably intoxicating seems arbitrary and indicative of the lack of evidence behind the inclusion of LSD. Moreover, the legal high salvia, which can also, in theory, produce comparable impairment for a short time, is used by young people at roughly twice the rate of the illegal hallucinogens mentioned (1.1% last year, vs 0.4% and 0.6% for LSD and mushrooms respectively). For all three drugs, it is difficult to imagine that specific inclusion in the new zero-tolerance law would serve a useful purpose.

Do you have any views on the alternative approaches as set out in policy option 2 and 3?

Policy Option 2, or a policy very closely modelled on it, is the choice that can be called evidence-based and rational. A risk-based approach which responds proportionately to the threats caused by alcohol, prescription drugs and illicit drugs is the only type that DrugScience could support, but one we would support without reservation. Option 2 would represent a marked advance from the current situation.

Policy Option 2 has a clear underlying logic. It says that in order that harm from accidents can be minimised, you should not drive when you are impaired because of drugs in your body. It makes no artificial distinctions between legal and illegal drugs, because such distinctions bear no relationship to issues of road safety.

DrugScience notes that the UK can be proud of having some of the safest roads in the world statistically. This is despite having a fairly high legal limit for alcohol comparatively, and a fairly high per-capita rate of alcohol consumption. This evidence suggests that the risk-based approach we take for alcohol is functioning effectively, that despite plenty of drinking, people are being discouraged from driving whilst impaired. A risk-based approach to other drugs is likely to work well.

The success of our risk-based drink-driving law has been attributed to the way that drink-driving became socially and morally unacceptable. A zero-tolerance approach, which penalises people who may not be impaired, is less likely to generate the same ‘buy-in’ from people, who are unlikely to feel that the law corresponds to a self-evident moral and social norm.

Option 2 imposes limits for 15 drugs, which along with the drink-drive limit, covers the vast majority of cases of drug-impaired driving that occur. The Expert Group’s approach also includes the collection of evidence which will enable the effectiveness of the law to be monitored and optimised. This monitoring will allow for further drugs, like LSD and mephedrone, to be added to the 15 if there is evidence that this is needed.

Alternatively, if the government cannot accept Option 2, we would urge the Government at least to accept the central parts of the Expert Panel’s advice;- to take a risk-based approach to all drugs without discriminating between illicit and licit drugs.

The Expert Panel’s view that LSD should be omitted because of lack of good evidence is a view DrugScience endorses. However, in preference to the Government’s zero-tolerance alternative for 8 drugs including LSD, it may be possible to instead impose a threshold limit for LSD and other psychoactive drugs, based at least on the minimal evidence which does exist, combined with expert opinion. DrugScience has experience of multi-criteria decision analysis, (MCDA) which provides a potential model for how thresholds may be created for LSD and other drugs like mephedrone based on a broader evidence-base when evidence on driving impairment specifically is lacking.

Alcohol DrugScience is seriously concerned by the simultaneous pursuit of a zero-tolerance approach to certain drugs whilst showing the opposite approach with alcohol. In recent months, the Government consulted on the possibility of lifting the restriction on alcohol sales at Motorway Service Areas owned by the Highways Agency, and have expressed an intention to take that proposal further. At a site not owned by the Highways Agency, Wetherspoons have already opened what they describe as hopefully “the first of many Wetherspoons on the motorway.”

Whilst we do not necessarily advocate for a lower drink-drive limit, for example of 0.05% BAC, DrugScience notes that a low or zero-tolerance limit for alcohol would be more justified than it is for some other drugs such as cannabis. If the Government feels a strong desire to take a very firm approach to driving whilst impaired through drugs, it could adopt a risk-based approach similar to that in Option 2 but reduce the specified limit for alcohol and all the other drugs. If a lower limit was chosen for alcohol, the Government would have greater justification in taking a more cautious approach across the board.

Policy Option 3 is plainly flawed for reasons explained in the Consultation document, and DrugScience agrees with the government in rejecting this option which is costly and has great potential for unwanted consequences.

We have not proposed specified limits in urine as we believe it is not possible to establish evidence-based concentrations of drugs in urine which would indicate that the drug was having an effect on a person’s nervous system. Do you agree with this (i.e. not setting limits in urine)? [Is there any further evidence which the Government should consider?

DrugScience agrees with the government’s argument here. Urine analysis does not produce the necessary quantitative information. We are glad to see that in this issue, questions of evidence are central to the Government’s position. This makes the broader question of why the Government is pursuing Policy Option 1 more perplexing. Whether a drug is having an effect on the nervous system is irrelevant to the Government’s zero-tolerance approach, it is only relevant to a risk-based approach which is interested in establishing a strong likelihood that drivers are posing a risk to road users before criminalising them.

Is the approach we are proposing to take when specifying a limit for cannabis reasonable for those who are driving and being prescribed with the cannabis based drug Sativex (which is used to treat Multiple Sclerosis)? If not what is the evidence to support your view?

The Government’s approach is not reasonable, even by the Government’s own arguments. When explaining why it is not pursuing Option 3, a zero-tolerance approach against all psychoactive drugs and medications even with a defence available for medical use, the Consultation document notes “This could deter patients from taking their prescribed medicines with the resulting untoward effects of not taking the medicine. It might also deter healthcare professionals from prescribing the medicines a patient needs, for fear of the impact on the patient.” The same arguments apply to Sativex; the proposed zero-tolerance approach is likely to cause unintended harm by preventing some patients receiving treatment that minimises their symptoms, and also nuisance to those who do persist with Sativex.

In the special case of Sativex, there are further tiers of decision-makers above the patient and prescriber who are likely to be affected by choosing this approach in such a way as the drug will reach fewer people who it may help. These tiers include Clinical Commissioning Groups, NICE, and central Government, who determine policy on regulating cannabis-based medicines. Currently, Sativex-use in the UK is very low, and in its infancy, and NICE have not yet recommended it as a first-line of treatment for any condition. It is only allowed through a recent exemption to Schedule 1 regulations following ACMD advice. It therefore seems likely that the direction of travel in the UK is set to continue towards the increased acceptance and utilisation of cannabis-based medicines, with benefits to NHS patients and to the UK-based pharmaceutical industry over the next few years.

The Consultation document is clear that the Government recognises that the medical use of psychoactive prescription drugs is legitimate and often consistent with safe driving. It must also recognise, as the Expert Panel noted, that psychoactive drugs may even improve driving safety. For example, an appropriate dose of Sativex or cannabis may allow a driver with painful spasticity greater freedom of movement and freedom from pain.

Do you have a view as to what limit to set for amphetamine? If so please give your reason(s).

DrugScience recommends accepting the advice of the Expert Panel, led by Prof. Wolff. They recommended a limit of 600µg/L, or half that much when alcohol is also present. The Consultation document notes that some individuals have commented that this limit is high. However, the reasons that this specified limit was chosen are clearly explained in the Expert Panel’s Report, and no actual counterarguments have been heard, except that the limit seems high. Amphetamines, DrugScience and Expert Panel agree, can sometimes be impairing, for example by increasing people’s confidence and impulsivity without necessarily increasing ability. Data from crashes demonstrates that. However, the situation is clearly complex, with other lines of evidence, such as experimental studies, that amphetamine in some contexts is unlikely to be impairing. Without some evidence that driving with levels of amphetamine lower than 600µg/L is comparable with the impairment of driving over the drink-drive limit, there is no reasonable basis for set the limit lower.

With stimulants, the link between dose and impairment is even less straightforward, providing even less reason to set a low limit. Much of the impairment is likely to result from the ‘comedown’, with accompanying exhaustion. Being ‘tougher’ than the evidence can support is not cost-free. It widens the net, increasing the direct costs of criminalisation to those arrested but also the indirect costs of extra prosecutions to taxpayers, and the knock-on costs to others.

Are there any other medicines that we have not taken account of that would be caught by the ‘lowest accidental exposure limit’ we propose for the 8 illegal drugs? If so please give your reason(s).

The answer to this question may not become fully clear until innocent people suffer the distress and potential harm of receiving false-positives. Using a risk-based approach consistently, instead of taking a risk–based approach to some drugs but not to others, reduces such risks of people producing false- positives. The zero-tolerance approach, where limits are set near zero, increases the risk that errors, of whatever cause, bring people over the measurement thresholds.

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