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Driving while under the influence of drugs

According to the figures from the annual Christmas drink and drug driving campaign (December 1 2009-January 1 2010) announced by the national Association of Chief Police Officers (ACPO):

  • Police conducted 223,423 breathalyser tests for alcohol – three percent were positive, failed or refused
  • In comparison, only 489 Field Impairment Tests were carried out by police for drug driving – a massive 18 percent were arrested 

The statistics are shocking both by the minute number of Field Impairment Tests carried out by police but more worryingly, by the huge percentage of drivers that were arrested and presumably went on to prove positive for drug driving.

These figures by (ACPO) are in line with previous research which showed that almost a quarter (22%) of those killed in road traffic accidents in the UK had illegal drugs in their bloodstream. The same research has suggested an increasing number of road traffic accidents where the presence of drugs in a driver's body may have contributed to the actual cause of the crash.

Driving under the influence of drugs whether prescribed medication or illegal substances, is just as dangerous as driving when drunk. Drug driving is most common among 20 to 24 year-olds, with clubbers being the most likely to take control of a car in a chemically altered state.

In a survey by the Scottish Executive's Road Safety Campaign, 81% of clubbers had driven after recreational drug use.  Many of those surveyed believed that cannabis had little or no impact on their driving skills, and some thinking that amphetamine use actually improved their driving skills.

Drugs affect your mind and body in many ways, you may think you are driving well but the effects of taking drugs can last for hours or even days. Often you think the drug has worn off, but the Police can still detect drugs in your bloodstream days after use.

Unlike alcohol, the law does not state any legal limit for drugs. This is because knowledge of how different drugs impair different people's driving ability is inconclusive. The extent of harm resulting from driving under the influence of drugs continues to be researched, although the current lack of a definite legal limit for drug driving can complicate possible prosecution.

Drug tests

If police officers suspect that you are driving under the influence of drugs, they can stop you on the roadside and observe you for outward signs of impairment caused by drug use. You'll probably be asked to perform a field impairment test, which involves testing your co-ordination skills.

For example, you may be asked to close your eyes and touch your nose (as certain drugs can cause you to misjudge the position of your nose) or stand on alternate feet for 30 seconds while counting aloud (certain drugs, particularly stimulants, could cause you to count too fast or lose count altogether).

The police officer will also check your pupils for unusual dilation - opiates (such as heroin and methadone) cause very small, 'pinprick' pupils, while stimulants (such as cocaine, ecstasy or speed) cause very large, 'saucer' pupils.

Refusal to take part in the tests is an offence in the same way as failure to provide a breath test under suspicion of drink-driving. The penalties for Drug Driving are the same as for drinking and driving. You could face a minimum of a one-year driving ban, a fine of up to £5,000 and six months in prison and if you kill someone while drug driving, you could spend many years behind bars.

Driving while under the influence of drugs

Tips and Advice - Article No 43 RoadDriver 2010

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