1 in 20 could go to the police station under false drug positives
By Aileen Colhoun
Monday, May 18, 2015 - 11:11
Where does blame lie when a drunk and a drug user crash?
In her debut article for FleetPoint, Aileen Colhoun, partner at law firm Hickman & Rose, looks at the legal implications for drug driving laws and how they are inforced
This month saw the first man convicted under new drug-driving laws in the UK. News of more arrests is coming from police forces across the country, as it is clear that new legislation, which came into force on 2 March, is starting to bite.
There has always been an offence of driving under the influence of drink but upper limits of specified drugs have been introduced under new legislation for the first time this year. While the new measures are laudable in principle, an analysis reveals disturbing disparities between our approach to drug and drink driving offences. The technology to detect the former is problematic too; 1 in 20 people may now suffer arrest for a false drug positive.
Under the newly enacted s5A Road Traffic Act 1988, the police may conduct saliva swab tests at the roadside on drivers they suspect have taken drugs. The trouble is the legal limits set for illicit substances are very low indeed.
Driving with a minuscule trace of cannabis in your blood could now lead to a minimum 12 month driving ban and a hefty fine. Cannabis traces can remain in the body for 3-5 hours after only a single joint and a habitual recreational smoker could fail the test even though no cannabis had been consumed for several weeks prior to taking it.
This zero tolerance position is justified by government advisers on the basis that there is no safe drug driving limit. However, in the face of evidence that impairment through alcohol consumption occurs at levels much lower that the current UK upper legal limit this approach raises interesting questions.
Consider the following scenario: Two drivers are involved in a road traffic accident. Both drivers are subjected to roadside testing. Driver A has recently been drinking but the breath/blood alcohol level does not exceed the legal limit. The other is a habitual recreational smoker of cannabis who has not smoked for a week. The risk is that the habitual recreational cannabis user will test positive and will lose his licence for 12 months for being over the drug driving limit, even though that driver may not have been to blame for the accident.
In a 2011 government report, alcohol impairment was mentioned as a contributory factor in around 9% of fatal road incidents resulting in 166 deaths. Drug impairment, in comparison, contributed to only 3% of all deadly road accidents that year. The government uses these findings to justify tougher drug driving measures whilst leaving the upper legal alcohol limit untouched.
Passive smokers could also fall foul of the new law. While the government insists that the limit has been set sufficiently low to safeguard passive exposure, scientific evidence suggests otherwise. In a recent study conducted on healthy non-marijuana smoking subjects who spent three hours in a Dutch café, THC (the primary ingredient in marijuana) was detectable in all fluid specimens taken three hours after leaving the venue, with 70% exceeding the new UK threshold.
The Department for Transport has so far only approved one “drugalyser” roadside device, the Securetec DrugWipe 3S. Its maker, Securetec, claims that its invention is “over 95% reliable”. But 95 per cent just is not good enough – it actually means that 1 in 20 may go to the police station under arrest on a false positive.
This puts anyone taking prescription drugs in the benzodiazepines – commonly prescribed for anxiety – class at risk. Those who exceed the prescribed dose, or have no prescription, are liable to prosecution.
Government advisor Professor David Taylor has recommended that prescription drug users make sure they carry their prescriptions when they drive. The need for this is particularly clear for prescription users of Sativex, a treatment that will also score positive for cannabis.
No-one seems to have considered the implications of such a draconian approach to drugs and driving.
Professor David Nutt, former chairman of the Advisory Council on the Misuse of Drugs, described the new law as “a recipe for injustice”. “It is clearly not about risk but trying to deter people from using illegal drugs” he explained.
While road safety is of paramount importance we need to ask ourselves if the new measures are truly about saving lives or a disguised salvo in the war on drugs.
Aileen Colhoun is a partner at law firm Hickman & Rose