This information is not available. A study of fatal accident victims during the period 1996-2000 showed that in a sample of 779 drivers and riders killed, 17 per cent. had traces of illegal drugs. In 8 per cent. of the sample the drug detected was cannabis, traces of which remain detectable in the body long after consumption.
No such estimate is made by the Department. A 2004 European Commission study “Impaired motorists: methods of roadside testing and assessment for licensing” co-funded by member states, examined the prevalence of illegal drugs in drivers. The summary of the results of the UK element of that study are at www.dft.gov.uk/stellent/groups/dft_rdsafety/documents/page/dft_rdsafety_611649-03.hcsp#P58_ 5194. The full report is at www.immortal.or.at/