Drug Driving Solicitors - The Defence Of Drug Driving Offence Allegations

As seen in our excess alcohol section, the Courts take these offences extremely seriously.

There are also further road traffic offences for driving, or attempting to drive, whilst unfit through drink or drugs, as well as drug driving.

To prove the allegation of driving whilst unfit through drink or drugs, no evidential sample is required. This means that the Prosecution do not need to prove what level of alcohol or drugs were in your system at the time that you were driving. The Prosecution will rely instead upon the Officer’s assessment that the driver was “unfit”, usually by completing an impairment test, in addition to evidence given by a police doctor of the impairment. The Prosecution must also prove that it was alcohol or drugs in the driver’s system that caused the unfitness to drive.

Sentences are in line with those where samples are provided. They range from compulsory minimum 12-month disqualification (or 36 months for a second offence within a 10-year period) to custody.

The defendant should be aware that these prosecutions are not just brought for illegal drugs, but also apply to over the counter medication or prescription drugs. Such medications should contain warnings if they are likely to cause impairment.

Defences available for these offences include:

➢ You were not impaired;
➢ You were not driving;
➢ You were not driving on a road or other public place;
➢ You were impaired, but this was not caused by alcohol or drugs.

In addition, there are the further offences of being “in charge of a vehicle” whilst unfit through drink or drugs. Again, this does not require evidence of the level of alcohol or drugs in your system. The sentence options include 10 penalty points, a substantial fine, a lengthy disqualification or custodial sentence.


If the driver provides a specimen for analysis, and the levels of drugs (either prescribed / legal drugs or illegal street drugs) exceed the legal limits the sentences can be severe. The likely outcome will depend upon the levels of drug/s present, whether there was also alcohol present, as well as other aggravating factors, such as;

➢ The location and time of day/night (i.e. was the driver likely to come into contact with other road users or pedestrians);
➢ Whether the driver was carrying passengers;
➢ The road and weather conditions;
➢ Whether there was more than 1 drug present in the sample.

The legal limits for each drug is set out below.

Benzoylecgonine 50
Cocaine 10
Delta-9-tetrahydrocannabinol (cannabis) 2
Ketamine 20
Lysergic acid diethylamide 1
Methylamphetamine 10
Methylenedioxymethamphetamine (MDMA) 10
6-monoacetylmorphine (heroin) 5
Clonazepam 50
Diazepam 550
Flunitrazepam 300
Lorazepam 100
Methadone 500
Morphine 80
Oxazepam 300
Temazepam 1,000

This is a technical area of law, and the procedure that must be followed is extremely complex. Our team of expert motoring defence solicitors will consider the steps taken in analysing your sample, to ensure that every stage was carried out correctly, both at the Police Station and in the lab.

Potential sentences for this offence include mandatory minimum 12-month disqualification, an unlimited fine, and custody.

  • We are specialist motoring defence solicitors, based in Plymouth in the South West. We provide expert legal advice and representation to clients both across Devon and Cornwall and nationally. Contact a member of our motoring legal team for an initial discussion about any road traffic matter.**