In 2007, 2,946 people died in collisions on UK roads. 16% of these collisions involved a driver who was over the legal limit for alcohol. That equates to 460 people dying in crashes that could probably have been avoided if someone hadn't had a drink.
The problems of drink driving are generally well known, but drivers aren't always aware that drugs can have a similar impact on their driving. Section Four of the Road Traffic Act 1988 states that "a person who, when driving or attempting to drive a motor vehicle on the road or a public place is unfit to drive through drink or drugs is guilty of an offence".
There are many perceptions about drug driving:
- "Drugs don't affect my ability to drive"
- "Drink driving is a much bigger problem"
- "Drugs can't be detected"
- "I won't get caught"
- "Not illegal" – or uncertainty about penalties.
These perceptions are wrong. Drugs can seriously affect your ability to drive and theire is a real possibility of being caught. The problem of drug driving is not merely related to drug misuse in terms of illegal drugs. The impact of some prescribed drugs and treatments (e.g. sedatives, anti-depressants and eye drops) are also relevant.
How substances can affect driving
Alcohol affects your ability to drive safely by slowing your reactions, reducing you field of vision and making it harder to judge speed and distance.
Cannabis is a relaxant which impairs concentration resulting in slower driver reaction times, impaired steering control and co-ordination. The drug can also induce feelings of paranoia, drowsiness and disorientation. The most intense affects last 2-4 hours and are magnified by even a small amount of alcohol.
Cocaine is a stimulant which can result in drivers misjudging speed and stopping distances. The drug can give drivers a feeling of overconfidence, which can lead to aggressive driving and increased risk taking. Cocaine can make you feel alert for about an hour, during which time you may react inappropriately. As the effect wears off there is a high danger of falling asleep at the wheel. Combining cocaine with alcohol can produce unexpected and dangerous results.
Ecstasy is a stimulant drug with hallucinogenic properties and can distort the driver's vision and affect concentration. Drivers under the influence of "E" show a significant decrease in their awareness of road dangers followed by severe fatigue the following day.
LSD is a hallucinogenic drug that can strongly influence a driver's senses. Drivers may react to objects or sounds that aren't there, placing themselves and other road users in danger.
Opiates (heroin) lead to slower reaction time, lethargy, sleepiness and impaired co-ordination.
Tranquillisers may impair driver reaction times and can cause drowsiness.
How much can I drink?
A pint of beer with 3.5% alcohol will typically have 2 units. However, this can rise to 2.3 units for 4% lagers and as high as 3 units for premium beers and cider with 5 - 5.5% alcohol. A bottle of wine contains enough for 6 glasses and you may have heard that each glass is one unit. However, a 125ml glass of average wine with 12% alcohol will have 1.5 units. Many wines are stronger than this, and many glasses are 250ml, so a single glass can be as high as 3 units. A bottle of alcopop will typically have 1.5 units of alcohol.
The legal limit for alcohol content in the blood is 80 milligrams per 100 millilitres of blood. However, you cannot translate this into a number of units that you can drink and still drive. The amount you can drink and legally be under the limit varies according to a number of factors, including age, gender, weight, food consumption, metabolism and the type of alcoholic drink. The only way to be sure you're under the limit is to not drink at all.
The same factors also affect how long it takes your body to process alcohol. It is often said that it takes 60 minutes to process a single unit of alcohol, but this can be much longer. Don't assume you are safe to drive the morning after an evening out, even if you are not hungover and feel fine. If you had a lot to drink, there is a good chance that you will still be over the limit for much of the next day. If you're caught, you will still face the same penalties as you would have the evening before.
I won't get caught
Many people think the chances of being caught drink driving are very low and that they can get away with it. They also think the chances of being caught driving under the influence of drugs are even more remote. In 2005, Police in the UK carried out more than 600,000 breath tests, catching 140,000 drivers drink driving. You might think that you will only be breathalysed if you have caused a collisions, but Police can require you to take a breath test if you have been involved in a collision, committed a moving traffic offence, such as failing to stop for a red light, or they believe you are driving, or have been driving, under the influence of alcohol.
There is a real possibility of being caught drug driving too. Drug driving is a priority for the Police, and drug use can be detected through the Field Impairment Test. Devices are also being developed that can detect drug use at the roadside, in much the same way as the existing breathaliser detects alcohol.
The Field Impairment Test (FIT) is designed to identify those driving under the influence of alcohol or drugs. It is made up of five stages:
- The pupil dilation test is designed to test for the presence of drugs.
- Counting out 30 seconds sounds easy, but drug users either under-read or over-read time.
- Walking in a straight line nine paces forwards and then back checks co-ordination and balance.
- Raising a foot in the air six to eight inches off the ground tests balance.
- Touching finger to nose with eyes closed test co-ordination.
If you're caught driving under the influence of either alcohol or drugs, you will face a fine of up to £5,000 or up to six months in prison. You will also receive a minimum driving ban of 12 months. If your job depends on driving, a driving ban could cause you to lose it, and the criminal record that comes with the conviction could harm your chances of finding another job.
But the potential consequences if you aren't caught are even worse. By driving under the influence of either drink or drugs, you endanger yourself and other road users. Causing a fatal accident while driving under the influence will lead to a two-year ban and a maximum of 10 years in prison.