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Blog: Proving drug driving to get easier

New drug drive limits mean police will no longer have to prove a suspect is unfit to drive, making convictions easier, writes lawyer Jeanette Miller.

Drugs and pills 

Last year, I wrote about the fairly complex procedure for investigating a motorist suspected of drug-driving.

At present, the tests police must conduct involve not only proving that a driver is under the influence of drugs, but that their driving is impaired as a result.

The current legislation states that: "A person who, when driving or attempting to drive a [mechanically propelled vehicle] on a road or other public place, is unfit to drive through drink or drugs is guilty of an offence."

But the law is changing to remove a lot of the difficulties police have at present in proving a motorist is "unfit" to drive.

Drug driving law change

Instead, if someone has a certain level of drugs in their system – and this includes legal drugs – there will be no need to prove that the motorist was impaired in any way.

So, a motorist may feel completely fine to drive but their blood level is what counts.

Is drug driving a real issue?

It appears that drug driving remains a primary concern for the public.

An annual survey for the Department for Transport looks at road-safety attitudes and behaviour among the British population.

The latest survey, from August 2013, found 28% of people chose drug driving as one of the top five road-safety issues for the government to address.

Drink driving topped the list, followed by speeding and using a handheld mobile phone at the wheel.

New drug driving test

Currently, the test for drug driving involves proving a motorist's driving was impaired.

But proving a driver is impaired and that the impairment is due to a drug can be complex and requires an element of subjectivity.

The government has held two consultations to change the law to make things easier for the police.

These concluded last month with public approval of recommended legal limits for 16 different drugs (both prescribed and illegal).

How will this change and when?

The new regulations will transform the offence of drug driving to be more like drink driving, with prescribed limits.

They are likely to come into force in autumn 2014.

The Department for Transport is trying to force through a zero tolerance approach to deter people from taking drugs and driving.

This is similar to that of Europe.

It is important to note that the limits are NOT set at zero, as drugs taken for medical conditions can be absorbed in the body to produce trace effects.

Different drugs are broken down at different speeds and that is reflected in the varying limits, expressed in microgrammes per litre of blood (µg/L), below:

Drug driving limits: Illegal drugs

  • 1. Benzoylecgonine, 50 µg/L (Contained in cocaine)
  • 2. Cocaine, 10 µg/L
  • 3. Delta–9–Tetrahydrocannabinol (cannabis and cannabinol), 2 µg/L
  • 4. Ketamine, 20 µg/L
  • 5. Lysergic Acid Diethylamide (LSD), 1 µg/L
  • 6. Methylamphetamine - 10 µg/L
  • 7. Methylenedioxymethaphetamine (MDMA – ecstasy), 10 µg/L
  • 8. 6-Monoacetylmorphine (6-MAM – heroin and morphine), 5 µg/L

Drug driving limits: General prescription drugs

  • 1. Clonazepam, 50 µg/L
  • 2. Diazepam, 550 µg/L
  • 3. Flunitrazepam, 300 µg/L
  • 4. Lorazepam, 100 µg/L
  • 5. Methadone, 500 µg/L
  • 6. Morphine, 80 µg/L
  • 7. Oxazepam, 300 µg/L
  • 8. Temazepam, 1000 µg/L

What can I do to make sure I drive within the law?

In the case of some prescription drugs, many people are unaware that getting in the car can result in a criminal offence being committed.

I suspect many medicines will contain more noticeable warnings when the new laws are introduced.

However, anyone taking regular medicine that you have been taking for years may wish to consult with your doctor about the limits and safe dosages.

If in doubt, take a taxi: the penalty for the offence, as with drink driving, is a minimum disqualification of 12 months and a maximum of six months in prison.

Lawyer and legal blogger Jeanette Miller is managing director at motoring law specialists Geoffrey Miller Solicitors

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Jeanette Miller

Jeanette Miller

Lawyer and legal blogger Jeanette Miller is managing director of motoring law specialists Geoffrey Miller Solicitors.

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