Being charged with drug driving can be a stressful experience, particularly for those who have never been to court before. A conviction carries a mandatory driving disqualification of at least 12 months, along with higher insurance premiums, and in more serious cases, even a short prison sentence.
We specialise in drug driving defence and can act immediately to review the evidence, identify any potential defence, and represent you in any court across England and Wales. If a conviction cannot be avoided, our focus shifts to seeking the lowest possible ban.
Facing a drug driving allegation? Call us for clear and expert guidance on 0333 240 7373, or email [email protected] for urgent advice from our expert solicitors.
How To Beat Drug Driving Charge
Drug driving is committed when someone drives or attempts to drive a vehicle on a public road, whilst over the drug drive limit (Road Traffic Act 1988, s. 5A).
There are two main ways to avoid a ban entirely:
Defences to Drug Driving
Not the driver: To convict, the prosecution must prove that you were driving the vehicle at the time of the alleged offence. If identity cannot be established – for example, where the vehicle was stationary or multiple people were present – this provides a complete defence. Example: you were found near a parked vehicle but witnesses could not confirm who had been driving.
Post-driving consumption: It is a full defence if the drugs were taken after you stopped driving. This often arises where a person consumes a small amount of an illegal drug after returning home, only for police to attend later following a report. Example: you drove home safely, then used cannabis before police later arrived and required a blood sample.
Procedural errors: The police must follow strict rules when taking, storing, and analysing blood or urine samples. Breaches of the law – for example, taking a sample without confirming medical fitness or failing to offer a portion for independent testing – can make the evidence inadmissible. Example: a healthcare professional took the sample even though you had just fainted, with no proper medical assessment recorded.
Analytical unreliability or delay: Toxicology results can be challenged if the integrity of the sample or timing of analysis is in doubt. Drugs break down rapidly, and excessive delay between taking and testing a sample can distort the readings. Example: your blood sample was stored for weeks before testing, or not refrigerated, raising questions about reliability.
Prescription-drug defence: If the substance was legally prescribed and you took it exactly as directed, you have a statutory defence under section 5A(3) of the Road Traffic Act 1988 – provided your driving was not impaired. Example: you were taking diazepam under medical supervision and followed the dosage instructions correctly.
Special Reasons Defence – Avoiding a Drug Driving Ban After a Guilty Plea
Even if you accept the offence, the court has discretion not to impose a driving ban if there were exceptional circumstances connected to the driving itself – known as special reasons (Section 34(1) of the Road Traffic Offenders Act 1988).
A special reason is a circumstance directly linked to the offence – not the offender – which the court considers sufficiently exceptional to justify avoiding a ban (Whittall v Kirby 1946). The driver must convince the court, on the balance of probabilities, that special reasons exist.
Courts usually expect the special reasons to be supported by independent or corroborative evidence, such as witness statements, CCTV footage, or medical documentation. Mere assertions by the defendant are rarely enough.
Unknowingly consuming drugs: This may apply where your drink or food was spiked, or you unknowingly took medication containing a controlled substance. Example: you attended a social event and later discovered your drink had been tampered with, leaving you over the legal limit without knowledge or intent.
Driving only a very short distance: If the vehicle was moved only a few metres, with no real danger to the public, the court may accept this as a special reason. Example: you started your car briefly to move it from an obstructive position outside your home. Cases such as Chatters v Burke [1986] have confirmed that minimal, low-risk movement can justify avoiding disqualification.
Driving in a genuine emergency: Where the driving occurred purely because of an urgent or unavoidable emergency, such as taking someone to hospital or escaping danger, the court has discretion to withhold a ban. The urgency and lack of reasonable alternatives must be clearly shown.
Reducing the Length of a Drug Driving Ban
Where a driving ban is unavoidable, our focus shifts to limiting its impact through detailed preparation and targeted mitigation. We gather and present supporting material such as medical reports, employer references, and evidence of good character to demonstrate why the shortest possible disqualification should be imposed. We also ensure any relevant mitigation about personal circumstances and difficulties are clearly highlighted to the court. By preparing structured and well-supported submissions, we maximise the chances of persuading magistrates to reduce the ban to the statutory minimum.
Expert Drug Driving Solicitors
Reeds Motoring are specialists in defending drug driving cases. We provide clear, practical advice from the outset – never raising false expectations but focusing on strong preparation and achieving the best possible result.
We can obtain the prosecution papers in advance of the court hearing, allowing us to fully prepare, advise on the likely sentence, any aggravating features, and explain the court process. This can reduce the understandable anxiety of having to attend court.
We challenge common court misconceptions about drug readings. Unlike alcohol, drug levels do not directly correspond to impairment. Magistrates sometimes assume that being several times over the limit must mean a driver was affected – but this is not how toxicology works. The statutory limits are set extremely low and as a parent compound breaks down, certain by-products may actually rise in concentration, creating an apparently higher reading long after any effect has passed. Explaining these scientific distinctions clearly can make a decisive difference to the outcome of a case.
With a dedicated London team over 20 offices across the country, we represent clients in Magistrates’ Courts nationwide. Meetings can be arranged in person or via Microsoft Teams.
Facing a drug driving allegation? Call us for clear and expert guidance on 0333 240 7373, email [email protected], or complete our online contact form for urgent advice from our specialist motoring solicitors.
Drug driving law under section 5A of the Road Traffic Act 1988 sets blood-concentration limits for a range of controlled substances. These limits are deliberately set at very low levels – often far below the point at which a person would actually be impaired. It is a ‘strict liability’ offence – if your blood sample shows a concentration above the limit, the offence is made out, even if you were driving safely and showed no signs of being affected.
- Cannabis (Δ9-Tetrahydrocannabinol / THC): 2 µg/L
- Cocaine: 10 µg/L
- Benzoylecgonine (cocaine breakdown product): 50 µg/L
- MDMA (3,4-Methylenedioxymethylamphetamine / ecstasy): 10 µg/L
- Ketamine: 20 µg/L
- LSD (Lysergic Acid Diethylamide): 1 µg/L
- Methamphetamine (Methylamphetamine): 10 µg/L
- Heroin (6-Monoacetylmorphine / 6-MAM): 5 µg/L
Unlike alcohol, there is no straightforward correlation between the reading and actual impairment. Each drug behaves differently in the body. As the parent compound breaks down, metabolites (its by-products) may increase in concentration, sometimes creating a reading that appears higher even after the effects have worn off.
Because of this, the reliability of the toxicology process is crucial. Delays in analysis, improper storage, or contamination can distort results. A skilled defence will examine whether the sample accurately reflected the driver’s condition at the time of driving, rather than hours later when metabolic changes may have altered the readings.
Lawfully prescribed medication can also lead to a drug driving charge if it affects your ability to drive safely. The legal limits for these medicines are higher than for illegal drugs, reflecting the fact that they are taken for valid medical reasons and usually under a doctor’s care.
Limits for prescribed or legal drugs:
- Clonazepam: 50 µg/L
- Diazepam: 550 µg/L
- Flunitrazepam (Rohypnol): 300 µg/L
- Lorazepam: 100 µg/L
- Oxazepam: 300 µg/L
- Temazepam: 1,000 µg/L
- Methadone: 500 µg/L
- Morphine: 80 µg/L
- Amphetamine: 250 µg/L
You can still be convicted if the prosecution proves that your driving was impaired. The statutory medical-prescription defence under section 5A(3) of the Road Traffic Act 1988 applies only if:
- The drug was prescribed for a medical purpose
- It was taken exactly as directed
- Your driving was not impaired
As with illegal drugs, the science behind the readings is complex. A person taking medication as prescribed can still test above the limit due to the way the body processes the parent compound and its metabolites. For example, morphine and methadone break down at different rates depending on metabolism, age, and health, which can cause readings to appear artificially elevated even where no impairment exists.
Expert toxicology evidence is often vital in showing that the concentration detected was consistent with lawful, therapeutic use and not impairment.
Driving whilst unfit through drink or drugs is sometimes charged when the police or prosecution cannot rely on a scientific test or evidential specimen. This often happens where the blood or urine sample tests negative for the common types of illegal drugs, but the police officer believes the driver was impaired by another substance.
This can include newer or less common drugs such as Mephedrone (also known as Meow Meow or M-Cat) or 2C-B (sometimes called Nexus). These are illegal under the Misuse of Drugs Act 1971 but are not covered by the statutory drug-driving limits and are not routinely screened for in laboratory testing.
These cases can also involve prescription or over-the-counter medication not covered by the statutory limits, such as sleeping tablets (zopiclone, zolpidem) or sedatives.
In some instances, the charge also arises because there was a delay or procedural problem in obtaining a sample, or because it became contaminated or unusable.
Report drug driving
Because there is no evidential reading, the prosecution must instead rely on observations suggesting that the person was unfit to drive. This often includes witness statements from police officers describing the person’s allegedly erratic driving, demeanour, slurred speech, coordination, or ‘glazed eyes’.
Field impairment tests can be carried out under section 6B of the Road Traffic Act 1988. These tests might include balance or coordination exercises, pupil reaction checks, or the well-known “walk and turn” test.
There are many innocent reasons why a person might appear impaired when they are not. Nervousness during a police stop, neurodivergent traits such as autism or ADHD, or an unrelated medical condition can all affect how someone may behaviour in the circumstances. In such cases, we can challenge the prosecution’s interpretation of the evidence, highlighting alternative explanations.
If you are convicted of drug driving, the court must impose a driving disqualification of at least 12 months. The exact length of the ban depends on a range of factors, including:
- The level and type of drug detected
- Whether there is evidence that your driving was impaired (officers often refer to poor quality driving or erratic behaviour in their statements).
- Any aggravating features, such as carrying passengers, being involved in an accident, or driving in poor weather conditions
Typical sentencing ranges:
- First offence with no aggravating features: 12–18-month disqualification and a fine
- Cases with aggravating factors: 18–24-month disqualification, often with a community order such as unpaid work or a curfew
- Serious impairment or repeat offending: 24–36-month disqualification, frequently accompanied by a community order or a custodial sentence
- Very serious cases: Up to 26 weeks’ immediate custody and a 36–60-month disqualification
In deciding the sentence, magistrates apply the national Magistrates’ Court Sentencing Guidelines, which assess both the level of harm and the offender’s culpability.
Early legal advice and strong mitigation can often reduce the length of a ban or in more serious cases, avoid a possible custodial sentence.
The courts have repeatedly underlined that drug driving cases turn on the reliability of the evidence and whether the legal threshold for the offence has genuinely been met. The following examples illustrate how careful analysis of toxicology and procedure can make a decisive difference.
Chatters v Burke [1986] RTR 320
Although decided in the context of drink driving, this case established principles that apply equally to drug driving. The court identified seven factors to be considered in deciding whether there are special reasons for not disqualifying: (1) how far the vehicle was driven; (2) the manner in which it was driven; (3) the state of the vehicle; (4) whether the driver intended to drive any further; (5) road and traffic conditions; (6) whether there was any danger, and (7) the reason for the vehicle being driven.
Watson v Adam (1996) SLT 459
Most courts will require expert evidence, particularly where the defence seeks to establish that a drink was unknowingly laced. However, where corroboration does not exist or is unavailable for some good reason, it remains open to the court to find special reasons if the defendant’s evidence is believed. The case illustrates that credible personal testimony, even without supporting expert evidence, can in rare cases be sufficient.
DPP v Bristow [1998] RTR 100
The Divisional Court held that when considering whether special reasons exist, magistrates should ask themselves what a sober, reasonable, and responsible friend of the defendant – present at the time but unable to drive – would have advised: to drive, or not to drive. Unless the court considers it a real possibility that such a friend would have advised driving, special reasons should not be found.
These authorities highlight that success in drug driving cases depends not only on challenging technical or procedural flaws, but on a deep understanding of how the law operates in practice. Knowing how courts interpret key issues – such as impairment, evidential timing, and special reasons – is critical to identifying viable defences and presenting them effectively.
Reeds Solicitors’ motoring specialists represent clients facing drug driving and other road traffic offences across England and Wales. From our network of more than 20 offices, we provide expert legal representation in London, the South East, the South West, the Midlands, the North West, and Wales. Our team attends Magistrates’ Courts nationwide and can assist wherever your case is heard.
Facing a drug driving allegation? Call us for clear and expert guidance on 0333 240 7373, email [email protected], or complete our online contact form for urgent advice from our specialist motoring solicitors.
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FAQ
Yes, most first-time offenders for drug driving receive a fine or community order in addition to a driving ban, but imprisonment is possible in more serious cases. Custody is usually considered where there was a high level of impairment, the driver had passengers in the car, an accident occurred, or the person has previous convictions. In some situations, the court may impose a suspended sentence with requirements such as unpaid work, rehabilitation activities, or a curfew instead of immediate imprisonment.
The time it takes for drug levels to fall below the legal limit varies widely depending on the substance, the amount taken, and your metabolism. Unlike alcohol, drug readings do not drop predictably, and you can remain over the limit long after any effects have worn off.
Cannabis (Δ9-Tetrahydrocannabinol / THC)
THC is stored in body fat and released slowly. Occasional users may remain over the 2 µg/L limit for 12–24 hours after smoking a single joint, while regular users can exceed the limit for much longer even when unimpaired.
Cocaine and Benzoylecgonine
Cocaine itself clears within hours, but its metabolite benzoylecgonine can remain in the bloodstream for up to two days. Someone who used a small amount the night before could still test above the 50 µg/L limit the next day despite feeling completely sober.
MDMA (3,4-Methylenedioxymethylamphetamine / Ecstasy)
MDMA and similar stimulants can remain in blood for around 12–24 hours. Even one tablet may leave a reading above the 10 µg/L limit the next morning.
Because the legal thresholds are set extremely low, the offence can be made out even when you no longer feel impaired. Timing of the sample, metabolism, and the reliability of the blood analysis are therefore critical when assessing whether a result truly reflects your condition at the time of driving.
If you have a previous drug or drink driving conviction within the last 10 years, the minimum ban is 3 years.
Toxicology results can be challenged if there are doubts about the way samples were taken, stored, or analysed. Drugs break down quickly, and delays or poor storage conditions can affect readings. Independent expert evidence is often key to showing that the result did not accurately reflect your condition when driving
Failing to provide a specimen of blood, urine, or breath without a reasonable excuse is a separate offence carrying the same penalties as drug driving.
A drug driving conviction can affect far more than your licence. In addition to a driving ban and potential fine or prison sentence, it can have lasting personal and financial repercussions. Insurance premiums often rise sharply, and some insurers may refuse cover altogether. Employment can also be affected, particularly in roles that involve driving or require a clean criminal record. In certain cases, international travel may become more difficult – for example, some countries such as the USA can refuse entry to those with drug-related convictions.
Our team are experts in motoring law, with a proven track record of defending clients accused of drug driving. We offer clear, straightforward advice you can trust, avoiding false assurances and focusing instead on practical strategies to achieve the best result.
With the ability to represent you in any Magistrates’ Court across England and Wales, we provide both nationwide coverage and personal guidance at every stage, from evidence review through to courtroom advocacy.