Drug tests don't FIT the Bill

As Andrew Legion reports, experimental roadside drug tests have proved unreliable.

Almost one-third of drivers who tested positive for illegal drugs were able to pass roadside sobriety tests, according to new research conducted by the University of Glasgow. The tests, conducted by specially trained police officers using so-called Field Impairment Tests (FIT), failed to detect a number of drivers who later were proved to have drugs in their bloodstream. In fact, the police achieved only a 66 per cent success rate in detecting drug-impaired drivers. Those escaping detection included a number with significant levels of heroin present in their system. Most of the motorists subjected to the FIT procedure were also asked for a saliva swab, which was later analysed by the university. The swabs were anonymous and could not be identified with any particular driver, but they did enable the police to check the veracity of the FIT results. Field Impairment Tests do not expose the presence of specific substances in the body. Instead they test a person's ability to carry out tasks involving balance, judgement, and ability to follow complex instructions, much as the American roadside sobriety test. Almost entirely subjective, FIT relies on the judgement and experience of the police officer conducting the test. In consequence, road-safety organizations, such as the RAC Foundation, have questioned whether the Field Impairment Tests are indeed 'FIT for purpose'. Researchers at Edinburgh University are testing a hand-held, electronic system, which could make the test more objective. In addition, equipment to detect the presence of drugs in the body is being developed by other UK scientists, although the Home Office has not yet formally approved any device for roadside use. Even so, the RAC Foundation believes that there is an urgent need to roll out objective roadside testing equipment to detect drug-drivers, and points out that drink-driving plummeted when the breathalyser was introduced. The fight against drug-driving is made more difficult by the need to prove not just that the driver has taken drugs, but also that their driving is impaired as a result. Whilst it is an offence under the Road Traffic Act 1998 for a person to drive while their '….ability to drive properly is for the time being impaired' by drink or drugs, there is no objective test for impairment, nor a legal definition of impairment in the Road Traffic Act; and there is no offence of driving in breach of a prescribed limit, as is the case for drink-driving. Unfortunately, the waters are further muddied by the fact that some proprietary medicines – which, of course, are also 'drugs' – could in certain conditions have the same effect upon a driver as illicit drugs, and may reveal traces of banned substances in much the same manner as proprietary medicines taken by athletes. In these circumstances, drivers who have taken nothing more illicit than, say, cough mixture, could find themselves on the wrong side of the law and potentially facing a driving ban. But whatever the shortcomings of roadside drug-testing, something must be done, urges the RAC Foundation, which points to some worrying statistics that give credence to its concerns. For example, in a recent Manchester survey, 45 per cent of drivers questioned had driven after taking drugs, and 68 per cent had been a passenger in a car driven by someone high on drugs. During the 2005 Christmas drink-drive crack-down in England and Wales, one in three drivers tested on suspicion of being drug-impaired was found to be so severely impaired that an arrest resulted. The police rightly argue that it is not simply a matter of enforcing drug-related laws. Even when sober, young people are already more likely to be involved in a road-traffic fatality than older drivers, and a cocktail of inexperience, alcohol and drugs vastly increases this risk. Sue Nicholson, Head of Campaigns for the RAC Foundation, said: "There has been a sharp increase in the number of young drivers killed on our roads, and we suspect drug-driving may play a large part in this. The latest research shows that some drug-drivers can escape detection by the Field Impairment Tests. While these are the best tests we currently have available to us, we believe there is an urgent need to improve detection techniques and equipment available to our police."