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Connolly, Johnny (2004) Drugs and driving. Drugnet Ireland, Issue 12, December 2004, pp. 14-15.

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Driving under the influence of drugs has been a statutory offence in Ireland since the Road Traffic Act 1961. The principal legislation in this area is covered under the Road Traffic Acts 1961 to 2002. Section 10 of the Road Traffic Act 1994 prohibits driving in a public place while a person ‘is under the influence of an intoxicant to such an extent as to be incapable of having proper control of the vehicle’. Intoxicants are defined to include alcohol, drugs, or any such combination. The Medical Bureau of Road Safety (MBRS) is the independent forensic body responsible for chemical testing of intoxicants under the Road Traffic Acts.

A recent nationwide survey carried out by the MBRS in 2000 and 2001 included an analysis of seven drugs or drug classes in 2000 blood and urine samples taken from drivers suspected of intoxicated driving.1 Of the 2,000 specimens chosen, 1,000 were under the legal limit for alcohol and 1,000 were over. The drugs involved were: amphetamines, metamphetamines, benzodiazepines, cannabinoids, cocaine, opiates and methadone. The purpose of the study was to determine current trends in driving under the influence of drugs (DUID) in Ireland and also to establish an evidence-based model to inform future road safety strategies.

The results suggest that there is a significant DUID problem in Ireland. Sixty-eight per cent of tested drivers with essentially zero levels of alcohol were positive for one or more drugs, suggesting a strong trend of increasing drug positivity with decreasing levels of alcohol. Cannabinoids were the most common drug class encountered. The study found no significant gender difference in the overall drug-positive results, although over 90 per cent of apprehended drivers were male. The typical profile of the apprehended and tested DUID driver is young, male, driving in an urban area with a low or zero alcohol level, with a specimen provided between the hours of 6 am and 9 pm and with a presence of cannabinoids. The study also identified a pattern of middle-aged drivers under the influence of benzodiazepines – a legally prescribed drug which can also impair driving.

The authors conclude that the study highlights the need for an education and awareness campaign in relation to DUID. There should also be an emphasis, they suggest, on the dangers associated with driving while under the influence of prescribed drugs. The study recommends that if the Gardaí suspect a case of DUID and obtain a negative or low alcohol reading then they should take a separate blood or urine specimen so as to detect the presence of a drug or drugs other than alcohol.

One of the outcomes of the MBRS study will be an evidence-based review of the legislation on driving under the influence of drugs. The study also highlights the difficulties of law enforcement in this area, and concludes that, ‘the goal of producing a valid, reliable and convenient roadside testing device for drugs is still paramount and not yet achieved’.2

A limitation of the study is that no random sampling of motorists occurred. Given that all of the blood and urine samples were taken from drivers apprehended by the Gardaí and suspected of driving under the influence of an intoxicant, the authors conclude that the information ‘does not provide a full picture of use of drugs in the general driving population’.3

1.       Cusack D, Leavy P, Daly L and Fitzpatrick P (2004) Driving under the influence of drugs in Ireland: results of a nationwide survey. Dublin: Medical Bureau of Road Safety.

2.      Ibid, p. 2.

3.      Ibid, p. 6.


Item Type
Publication Type
Irish-related, Open Access, Article
Drug Type
Substances (not alcohol/tobacco)
Issue Title
Issue 12, December 2004
December 2004
Page Range
pp. 14-15
Health Research Board
Issue 12, December 2004
Accession Number
HRB (Available)

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