The prosecution must prove that your driving ability was impaired at the time of driving due to the presence of an illegal substance.
Driving Whilst Impaired Through Drugs
The difficulty for the prosecution is establishing what level of drugs can be in a person’s system before they become impaired.
Expert Motoring Offences Solicitors
At GT Stewart Solicitors & Advocates, we understand that being charged with a motoring offence can be stressful, disruptive, and carry serious consequences. From speeding and driving without insurance to more serious allegations such as dangerous driving or driving under the influence, our specialist motoring offences team provides expert advice and representation at every stage of the process.
We guide our clients through police investigations, court proceedings, and potential licence or penalty issues, ensuring that all legal options are carefully considered. Our approach combines practical solutions with a strategic focus on protecting your driving record, liberty, and future.
Whether you are facing a single motoring charge or complex, multiple allegations, our solicitors act quickly to provide clear advice, robust representation, and support tailored to your circumstances.
Experienced Motoring Offences Lawyers
Our specialist motoring offences team has extensive experience representing clients facing a wide range of road traffic matters, from speeding, careless or dangerous driving, to more serious allegations such as driving under the influence or driving without insurance. We provide clear advice and representation at every stage, including police investigations, court proceedings, and licence-related matters.
We can help dramatically improve your chances of being found not guilty or avoiding disqualification. Email GT Stewart at roadtraffic@gtstewart.co.uk to speak with a member of our specialist motoring law team, or use our online enquiry form. We will respond at a time and date convenient to you, ensuring that you receive prompt, personalised advice tailored to your case.
Driving Whilst Impaired Through Drugs
Initially, the police will carry out a FIT test (Field Impairment Test) at the roadside to determine your level of impairment (if any). The officer carrying out the test must refer to standard guidelines and procedures for testing and will make observations in relation to the following:
- The size of your pupils (The Pupil Measure Test);
- Your balance and judgement (The Romberg Test);
- The Walk and Turn test;
- The one leg standard test; and
- The finger to nose test
If the officer decides that you have failed the test you will be required to provide a specimen of blood (or urine) at the police station. The police must offer you a sample of blood to take away with you from the police station. We would recommend that you arrange to have your sample tested as soon as possible. If you do not consent, you will be charged with an offence of failing to provide a specimen, unless you have a reasonable excuse such as a fear of needles.
It is not enough for the prosecution to prove that there was a drug present in your system, they must also prove that you were unfit through drugs. This is something that we are able to challenge on your behalf given the number of different factors which can influence the results of the FIT test. Contact GT Stewart at roadtraffic@gtstewart.co.uk in order to get urgent specialist legal advice.
Driving with Excess Drugs
The difficulties of successfully prosecuting a driver for driving whilst impaired through drugs forced new legislation to be introduced in 2015 by introducing specified legal limits for both legal and illegal drugs in order to measure an accepted level of usage before driving. The prosecution now have to establish that you were driving and the proportion of a specified drug measured in your blood is found to be over the prescribed limit.
The new legislation set limits for 17 ‘controlled drugs, some of which are used for widespread medicinal purposes (8) and those which are not with amphetamine being categorised separately.
| Controlled Drug | Limit (micrograms per litre of blood) |
|---|---|
| Benzoylecgonine | 50 |
| Clonazepam | 50 |
| Cocaine | 10 |
| Delta-9-Tetrahydrocannabinol (cannabis) | 2 |
| Diazepam | 550 |
| Flunitrazepam | 300 |
| Ketamine | 20 |
| Lorazepam | 100 |
| Lysergic Acid Diethylamide | 1 |
| Methadone | 500 |
| Methylamphetamine | 10 |
| 6-Monoacetylmorphine | 5 |
| Morphine | 80 |
| Oxazepam | 300 |
| Temazepam | 1000 |
| Amphetamine | 250 |
Our Services
At GT Stewart Solicitors, our specialist motoring offences team provides clear, practical advice across the full range of road traffic matters. Whether you are facing a speeding allegation, a drink or drug driving charge, or a more serious offence such as dangerous driving, early legal advice can make a significant difference to the outcome of your case.
We understand that for many clients, their driving licence is essential for work, family responsibilities, and day-to-day life. Allegations can carry penalty points, fines, disqualification, or even imprisonment. Our experienced lawyers will assess the evidence, advise you on your options, and build a strong defence where appropriate.
Below you will find guidance on the most common motoring offences we deal with, together with practical information about the legal process and how we can help protect your licence and your livelihood.
Click below to read detailed advice on each motoring offence.
Parking Fines and Offences
Why Choose GT Stewart?
“We will do all the law permits to keep you on the road”
GT Stewart have a proven track record of success with defending driving offences and know exactly how to prepare an effective defence in order to give you the best chance of winning your case.
Our Expert Lawyers are ready to Help
GT Stewart has established itself as a leading firm in the UK, specialising in both private cases and also Legal Aid work.
Meet some of our Motoring Offences team
Speak to one of our Motoring Offences Solicitors
Our Tenacity Results in Success
We represented a client charged with possessing an offensive weapon in a private place after police discovered a sword at her home address.
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We represented a a law student who was charged with two counts of assaulting emergency workers.
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We represented a client in a successful appeal against sentence, following a referral by the Criminal Cases Review Commission (CCRC). The Court of Appeal reduced our client’s sentence by 148 days, correcting a long-standing legal oversight. The CCRC referred the case, following our submissions that the lower Court erred in failing to deduct time in prison abroad pending extradition.
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Client Testimonials
"Phoebe Cole’s has dealt with a couple of my cases at the same time and has been very helpful and even goes out her way to get things done even in her own time out of work hours which shows her dedication, super hard working! Thank you Phoebe."
"I was charged with conspiracy to arm robbery and remanded in to court Hassan dealt with my case managed to get me bail and put through a lesser plea of assisting an offender with basis of plea and today I was giving a suspended sentences. And my co defendant got 5 years in prison. Make sure you reach out to them best in the game."
"Hassan was able to quickly and efficiently support us and advocate for us when my son got in a spot of bother, and helped us to navigate the system"
"Hasan represented me in relation to a dangerous driving case involving extremely serious allegations. The incident involved driving at dangerous speeds with my vehicle door open, colliding with police and other vehicles, and a prolonged police pursuit, all while I was already on police bail for unrelated matters. From the outset, Hasan gave me clear, honest advice that it was in my best interests to plead guilty in order to receive maximum credit. He worked tirelessly on my case, obtaining a psychological report that provided compelling mitigation and taking detailed character references from my family and friends to present the strongest possible case on my behalf. At court, Hasan’s advocacy was exceptional. Thanks to the mitigation he prepared and the way he presented my case, I received a suspended sentence instead of immediate custody. The judge expressly stated that I would have been sent to prison had it not been for the mitigation put forward. I genuinely believe I owe my liberty to Hasan. I cannot thank him enough for his professionalism, dedication, and outstanding representation. I would highly recommend him to anyone in need of an exceptional defence solicitor."
"Harry represented me throughout a lengthy and complex criminal case spanning approximately three years. The matter ultimately concluded with a Not Guilty verdict, and I appreciated the effort and commitment he showed in preparing the case over that period."