Letter: Drug driving

Sir: It should be common sense that it is dangerous to use tranquillizers while operating a motor vehicle (report, 23 October). But common sense is only as good as the myths and propaganda that guide our perception.

A recent study conducted by the University of Adelaide and reported by the Canberra Times in Australia shows counter-intuitive results regarding driving under the influence of another drug, namely marijuana.

Analyses of blood samples of 2,500 drivers injured in accidents in southern Australia and police reports of those accidents showed that drivers under the influence of marijuana were culpable for 50.6 per cent of the accidents they were injured in, compared to drug-free drivers who were found to be culpable in 53.5 per cent of the accidents that they were injured in.

Among these 2,500 drivers, those whose blood-alchohol concentration was 0.05 per cent or higher were found to be culpable in about 90 per cent of the accidents that they were involved in.

These results are being used to caution policy-makers against diverting funds from anti-drunken driving campaigns to campaigns against driving under the influence of drugs.

LARRY A STEVENS

Springfield, Illinois, USA