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What to Expect from a Drug Driving Test

Many presume that a drug driving charge only applies to those under the influence of illegal drugs.

This isn’t necessarily true; drug driving charges can also be brought against those who have taken prescribed or over-the-counter drugs. Just like illegal drugs such as cannabis, cocaine or LSD, legal medical drugs can cause side-effects that may make you unfit to drive.

It’s dangerous to drive after consuming illegal or legal drugs, as there are many ways they can impede your reaction time, vision, coordination, perception and concentration. Under the influence, users may also experience tremors, nausea, dizziness and lethargy, as well as overconfidence and paranoia.

These symptoms can vary depending on the type of drug taken, the dose and the person taking them.

If a police officer suspects you are driving under the influence, you will be stopped and asked to take part in a series of five Field Impairment Tests (FITs).


Pupillary Test

This is where the driver’s pupils are measured as dilation or constriction can be evidence of drug use.

Romberg Test

The driver must stand with their head tilted backwards and their eyes closed and be able to accurately state when 30 seconds has elapsed. Those under the influence of drugs may estimate 30 seconds to pass either too quickly or too slowly and their balance may be affected, causing them to sway or be unable to hold the required position for even a short period of time.

Walk and Turn Test

Walking heel-to-toe in a straight line, the driver must count their steps and keep their eyes on their feet. The officer will observe for any loss of balance, footing or inability to keep to the line and turn when instructed.

One Leg Stand Test

Another balance test in which the driver must stand on one leg and count out loud. Any swaying, loss of balance or deviation from the instructions will be noted.

Finger-To-Nose Test

To test depth perception, the driver will be asked to touch the tip of their nose with one finger whilst their head is tilted back and their eyes are closed. The officer should  specify which hand they’d like the driver to use.


In the event that the tests cannot be completed properly – or the driver refuses to take the test(s) – an arrest is up to the officer’s discretion. At the police station, a Forensic Medical Examiner will take a blood test. If drugs are found in your system, this could lead to a criminal charge.

If found guilty, the penalties are similar to drink driving and on top of a mandatory 12-month driving ban, you may receive a fine of up to £5,000 and a criminal record.


To find out more or to discuss your options, contact our specialist solicitors.