Behaviours – Drugs and Medication

Police Powers and Screening Tests

Police officers are trained to administer screening tests to drivers suspected of driving while impaired.

On the side of the road

If a police officer suspects that you have drugs or certain types of medication in your system, you may be required to submit to physical coordination tests or take a saliva test.

Physical coordination tests

Horizontal gaze nystagmus test: eye movement test

The police officer will have you follow a pen with your eyes in order to detect the presence of nystagmus (involuntary, jerky eye movements).

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Test du mouvement des yeux

Eye movement test – video in French only

Transcript :

Walking test: walk-and-turn test

The police officer will ask you to walk on a straight line and turn around.

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Test de la démarche

Walking test – video in French only

Transcript :

Balance test: one-leg stand test

The police officer will also test your ability to perform several tasks simultaneously, such as walking in a straight line or standing on one leg while counting out loud. Under the influence of drugs, it may be difficult to follow all of the police officer's instructions.

Failing these tests is enough to place a driver under arrest.

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Test de l'équilibre

Balance test – video in French only

Transcript :

Saliva test

If the police officer suspects that you have drugs or certain types of medication in your system, you may be required to take a saliva test. These tests are enough for the police officer to place you under arrest and bring you to the police station.

At the police station

Drug recognition experts

At the police station, specialized police officers administer a series of more extensive tests to determine whether you are impaired by drugs, medication or alcohol.

Among other things, they will examine:

  • pulse, body temperature and blood pressure
  • the eyes, in particular the size of the pupils
  • the insides of the nostrils and mouth
  • muscle tone (depending on the drug used, muscles may be either more rigid or more relaxed)
  • the arms and neck, in order to find possible injection sites

After the evaluating officer has done these examinations, you will also be required to provide urine or saliva samples for toxicological testing. If the results test positive, they will be submitted as evidence to the Directeur des poursuites criminelles et pénales.

Blood tests

The police officer may require you to provide a blood sample for analysis.
If the results of the blood test show that you have a blood drug concentration equal to or over the concentration prescribed by federal regulation, criminal charges may be brought against you.