Drug Driving


Drug Driving UK – The Law

Drug driving is the term used to describe anyone who gets behind the wheel of a vehicle under the influence of any substance (legal or illegal) that is likely to impair their driving ability.

Drug Driving Law

Under Section 107, Schedule 7 of the Railways and Transport Safety Act 2003:

  • It is an offence to drive a motor vehicle while under the influence of a controlled drug.

The Railways and Transport Safety Act 2003 Section 107 & Schedule 7 – Road traffic: testing for drink and drugs, contains new sections designed to replace section 6 of the Road Traffic Act 1988 (breath tests) with new powers for Police to administer three preliminary tests:

  • a breath test
  • a test indicating whether a person is unfit to drive due to drink or drugs
  • a test for the presence of drugs in a person’s body

Section 6 of The Railways and Transport Safety Act 2003 enables a Police Officer to require a person to co-operate with any one or more of the preliminary tests in certain circumstances.
Any person who fails to cooperate, without a reasonable excuse, would be committing an offence.

These circumstances include where a Police Officer reasonably suspects that the person:

  • has been driving, attempting to drive or in charge of a motor vehicle on a road or other public place while having alcohol or a drug in his body or while unfit to drive because of a drug and still has alcohol or a drug in his body or is still under the influence of a drug
  • has committed a traffic offence while the vehicle was in motion
  • where an accident occurs owing to the presence of a motor vehicle on a road or other public place

Roadside Drug Testing.

The law does not state any legal limit for drugs like it does for alcohol. This is because research and knowledge of how different drugs impair different people’s driving ability is inconclusive.
However, anyone drug driving may think that just because they pass a test for alcohol they will be let off.
This is not the case because Police Officers can also prosecute a driver who is unfit through drugs and have various methods of detecting and proving these offences.

One specific form of drug test the police may use is the Field Impairment Assessment (FIA).
It can be administered by trained officers at the roadside and is based on an observation of impairment, rather than a biological test. Police use five field impairment tests which are simple to complete if the person is not affected by any substance, but difficult if they are.

Prior to conducting the FIA test, Police Officers can detect possible drug use by checking the effect that drugs have on eyes such as:

  • opiates  (such as heroin and methadone) cause very small, ‘pin prick’ pupils
  • cannabis causes the blood vessels in the eyes (and elsewhere) to become larger giving a bloodshot appearance
  • ecstasy significantly enlarges the size of pupils
  • stimulants (such as cocaine, ecstasy or speed) cause very large, ‘saucer’ pupils

The Police Officer will then continue with the Field Impairment Assessment that includes five tests:

  • The Pupil Measure Test. Examination of the driver’s eye pupil size, condition and reaction to light using a pupil measure.
  • The Romberg Test. This test assesses the driver’s balance and judgement of time. The subject is asked to tilt their head back slightly, close their eyes and estimate the passage of thirty seconds.
  • The Walk and Turn Test. The subject must walk heel to toe along a straight line, counting their steps out loud and looking at their feet while doing so.
  • The One Leg Stand Test. The subject must stand on one leg while counting out loud.
  • The Finger to Nose Test. With the head tilted slightly backwards and eyes closed, the subject must touch the tip of their nose with the tip of their finger with the hand indicated by the officer.

If a Police Officer believes the driver is guilty of drug driving they will be arrested and taken to a police station where they will be examined by a doctor.

Refusal to participate in the tests is an offence in the same way as failing to provide a breath test under suspicion of drink driving and will also result in the drivers arrest and removal to a Police Station.

If you’re taken to the station

If you have been stopped on suspicion of drug driving you are likely to be arrested and taken to a police station. On arrival at the police station you may be tested for the presence of drugs through a blood or urine sample. This is then sent to a Forensic Scientist for examination. The police do not have to wait for you to sober up or resume consciousness in order to do this. A doctor can also carry out a blood test to see if you’ve been incapacitated due to medical reasons, such as illness or intake of prescribed medicine.


Following examination of the sample by Forensic Scientists they will submit a report to give an indication to what drugs were found within the blood or urine sample and what levels they were at. The forensic scientist would then provide an opinion as to whether or not the readings would normally cause a person to be impaired because of drugs.
Consideration would also then be given to the results of the Field Impairment
If you were found to have any drugs on your person at the time of arrest, possession of illegal drugs is an offence and you could potentially be handed a heavy penalty (including a fine and/or prison sentence) for possession or intent to supply.

The law is restricted in the prosecution of drug driving cases as it is difficult to establish the effects that different drugs have on different people and whether it renders them incapable of driving.

Penalties for drug driving

The drug driving penalties are the same as for drink driving.
You could receive:

  • a minimum 12-month driving ban
  • a criminal record
  • a fine of up to £5000

In addition:

  • there will be a specific record on the driving licence for eleven years that details a conviction for drug driving
  • if the driver is convicted of causing death by dangerous driving, they will receive a prison sentence of up to fourteen years
  • if they drive for work their employer will see the conviction when they have to produce their licence
  • car insurance will increase significantly
  • any drug-related conviction may mean encountering difficulties getting permission to enter countries such as the USA

Legal / Prescribed Drugs

Driving is not only affected by illegal drugs. Thought should be given to driving when taking prescribed drugs as well.
Drugs affect the way you think and behave, and this can have a significant impact on your sense of judgment and reaction times.
Always read the label if you’re taking prescribed medication. Antihistamines (often used in flu and hay fever remedies) and tranquillisers (used to treat anxiety, depression and sleeping disorders) may significantly affect reaction times and/or cause drowsiness. If the label advises against ‘operating heavy machinery’, this also means driving motor vehicles.
Also consider the effects of non prescribed medicines and read the labels, some labels state “may cause drowsiness”.
If you have any concerns or doubts, consult your doctor or Pharmacist.

Drug Classification

Controlled drugs (CDs) are drugs which are defined by the Misuse of Drugs Act 1971 as “dangerous or otherwise harmful” and have the potential for abuse or misuse.

Offences under the Act include:

  • possession of a controlled drug unlawfully
  • possession of a controlled drug with intent to supply it
  • supplying or offering to supply a controlled drug (even where no charge is made for the drug)
  • allowing premises you occupy or manage to be used unlawfully for the purpose of producing or supplying controlled drugs

The Misuse of Drugs Act 1971 divides drugs into three classifications:

Class A Drugs
Cocaine, crack, crystal meth, ecstasy, heroin, LSD (acid), magic mushrooms, methadone, opium, and any class B drug prepared for injection;
Less common substances: dextromoramide (e.g. Palfium), dipipanone, fentanyl, mescaline, pethidine, PCP, all parts of the seeds of the opium poppy (after mowing);
Maximum penalties: seven years in prison and/or a fine for possession, life imprisonment and/or a fine for possession with intent to supply.

Class B Drugs
Amphetamines (speed), barbiturates, cannabis, codeine. This class also includes the following less common substances: dexamphetamine, dihydrocodeine (DF0118), methaqualone, methylphenidate hydrochloride (Ritalin), phenmetrazine (Filon);
Maximum penalties: five years in prison and/or a fine for possession, 14 years in prison and/or a fine for possession with intent to supply.

Class C Drugs
Ketamine, some tranquillisers like Temazepam, the supply of anabolic steroids;
Maximum penalties: two years in prison and/or a fine for possession, five years prison and/or a fine for possession with intent to supply.

The chart below details the penalties for possession of drugs and possession with intent to supply.

Offence Court Class A Class B Class C
Possession Magistrates 6 months/
£5000 fine
3 months/
£2500 fine
3 months/
£500 fine
Possession Crown 7 years/Unlimited
5 years/
unlimited fine
2 years/
unlimited fine
Possession with intent
to supply
Magistrates 6 months/
£5000 fine
6 months/
£5000 fine
3 months/
£2000 fine
Possession with intent
to supply
Crown Life/Unlimited
14 years/
unlimited fine
14 years/
unlimited fine

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