Drug saliva test in Belgium: when can the police require it?

For alcohol, the police can ask any driver to blow into a breath test, without any indication of drinking. For drugs, it is different: outside the case of an accident, the officer must first observe signs of recent drug use. They do this using a standardised checklist. Only if that checklist is positive does a saliva test follow.

Since 1 October 2024, a new version of this checklist has applied, and the threshold for a saliva test is lower than before. This article is part of our overview of drug driving.

The legal basis

The checklist is set out in Article 61bis, §2, 1° of the Road Traffic Act (loi relative à la police de la circulation routière). The model and the rules for using it were laid down by the Royal Decree of 17 September 2010, substantially amended by the Royal Decree of 3 September 2024.

The checklist is a passive observation. The officer looks at you, talks to you and notes what they observe. You cannot refuse this observation. It must be carried out objectively and impartially. The officer goes through the whole checklist and ticks every sign they observe.

The new checklist: part A and part B

Part A: outward signs

Part A lists the classic signs of recent drug use, divided into several sections, such as the eyes, behaviour, speech and motor skills. Think of glassy eyes, dilated or constricted pupils, restlessness, an unsteady gait or slow reactions. Since 2024, part A also contains a section for other signs of a state comparable to drunkenness (Article 35 of the Road Traffic Act), for example because of medication.

Part B: strong indications

Part B is new and contains three signs that were previously in the general list:

you say yourself that you recently used drugs;
there is a smell of drugs, such as cannabis or a chemical smell;
drugs or drug paraphernalia are found.

When does a saliva test follow?

The checklist is positive if there are:

at least three signs, spread over at least two sections of part A, or
at least one sign from part B.

An example: if the officer only notes shiny eyes, or shiny eyes and an unsteady gait, the procedure stops. Shiny eyes, watery eyes and an unsteady gait, spread over two sections, are enough, on the other hand. If the car smells of cannabis, a saliva test follows immediately.

After an accident

In the case of a traffic accident with material damage or bodily injury, the checklist does not have to be gone through. The police can immediately require a saliva test.

A positive checklist is not proof

The checklist only opens the way to the saliva test. A positive checklist does not prove that you were under the influence. Tiredness, illness, nervousness or an allergy can cause the same signs.

For your defence, however, the checklist can be important. Was it filled in completely? Are the signs in the required sections? Was there a reason not to use a checklist, such as an accident? If a saliva test was carried out without a positive checklist and without an accident, that is an irregularity. It does not automatically lead to an acquittal, but the judge must assess it. See our article on errors in the police report.

The saliva test

The saliva test is a rapid test carried out on the spot (Article 61bis, §2, 2° of the Road Traffic Act). Since April 2019, the police have used a disposable test that detects five groups of substances: cannabis (THC), amphetamine, methamphetamine and MDMA, opiates and cocaine.

How the test works

The officer asks you to rub a swab for about 15 seconds against the inside of your cheek, from one side of your mouth to the other. As soon as a colour indicator on the swab changes colour, there is enough saliva. The device analyses the sample on the spot.

The instructions say not to eat, drink or smoke for the 10 minutes beforehand, as the saliva could be contaminated. Tests show, however, that common products such as coffee, cola, toothpaste, mouthwash, chewing gum, orange juice or cough sweets do not give a false positive.

Reading the result

The test works differently from what you might expect:

the control line must always appear, otherwise the test is not valid;
if a line appears for a substance, the result is negative for that substance;
if no line appears for a substance, the result is positive.

If the result stays below the legal thresholds, the procedure stops. If it is positive, a saliva analysis follows or, if that is not possible, a blood test. See our article on saliva analysis, the blood test and the counter-analysis.

What a positive saliva test means straight away

A positive saliva test leads to a temporary 12-hour driving prohibition and the immediate withdrawal of your driving licence for 15 days. See our article on immediate withdrawal of your licence. If the offence is proven, you also pay the costs of the test.

Refusing?

You cannot refuse the checklist itself. Refusing a saliva test without legitimate reason is an offence and also leads to the immediate withdrawal of your driving licence. See our article on refusing a test.

Frequently asked questions

Can the police require a drug test without a reason?

No. Unlike for alcohol, the police must first observe signs of recent drug use by means of the standardised checklist. Only if it is positive does a saliva test follow. After a traffic accident with damage or injuries, the police can skip the checklist and require a saliva test directly.

Is the smell of cannabis in the car enough for a saliva test?

Yes. Since 1 October 2024, the smell of drugs has been in part B of the checklist. A single sign from part B is enough for a saliva test. The same applies if you say yourself that you recently used drugs, or if the police find drugs or drug paraphernalia.

Can I refuse the checklist?

No. The checklist is a passive observation: the officer looks at you, talks to you and notes what they see. You do not have to actively cooperate, and so you cannot refuse it either. The saliva test that follows cannot be refused without legitimate reason.

How long does a saliva test take?

The sampling itself takes about 15 seconds: you rub a swab against the inside of your cheek until a colour indicator changes. The device then gives a result within a few minutes. If the test is positive, a saliva analysis follows: you then keep a collector under your tongue for a few minutes, up to a maximum of five minutes.

Can coffee or toothpaste give a false positive on the saliva test?

According to the manufacturer’s tests, no. Products such as coffee, cola, toothpaste, mouthwash, chewing gum, orange juice and codeine-free cough sweets did not give false positives. The instructions do, however, say not to eat, drink or smoke anything for the 10 minutes before the test.

Have your case reviewed

Have you been summoned (citation) to appear after a checklist and a saliva test? We check whether the procedure was followed correctly. Get in touch with us.

Law as at 28 September 2026. We update this article when the rules change.

Drug checklist: when can the police make you take a saliva test?