by Alexandra Mamo

In anticipation of the upcoming legalization of marihuana, the government is ensuring that police officers become more skilled in identifying drivers who are impaired by drugs on Ontario’s highways.

The law currently allows police officers to go through three steps to determine if someone is driving while impaired.

Step One

At the first stage, police officers make observations to develop a reasonable suspicion that a person has a drug in his or her body, and has operated a motor vehicle within three hours. These observations, such as smelling an odour of marihuana or observing bloodshot eyes, can be made during a normal traffic stop.

Step Two

Once this reasonable suspicion has been developed, the Criminal Code allows police officers to demand that a person immediately perform a physical coordination test. The purpose of this test is to enable the officer to look for signs of impairment and decide whether a further “evaluation demand” can be made. The standard field sobriety tests prescribed by regulation are:

      (a) the horizontal gaze nystagmus test (involuntary bouncing or jerking of the eye when a person is impaired by alcohol or certain drugs);
      (b) the walk-and-turn test; and
    (c) the one-leg stand test.

Step Three

If, as the result of a physical coordination test, a police officer has reasonable grounds to believe that a person has committed the offence of impaired driving as a result of the consumption of a drug, the officer can demand that the person submit to an “evaluation” by an “evaluating officer” at the Police Station.

The “evaluating officer” is someone who is accredited by the International Association of Chiefs of Police as a Drug Recognition Expert. The purpose of the “evaluation” is to determine whether the person’s ability to operate a motor vehicle is impaired by a drug or by a combination of alcohol and a drug.

At this stage, the Drug Recognition Expert will ask the driver to go through the following tests and procedures:

      (a) a preliminary examination that measures their pulse and determines that their pupils are the same size and that their eyes track an object equally;
      (b) eye examinations: consisting of the horizontal gaze nystagmus test, the vertical gaze nystagmus test, and the lack-of-convergence test;
    (c) divided attention tests, consisting of:
         i. the Romberg balance test (stand, feet together and eyes closed)
        ii. the walk-and-turn test,
       iii. the one-leg stand test, and
       iv. the finger to nose test, which includes the test subject tilting the head back and touching the tip of the nose with the tip of the index finger while keeping his or her eyes closed;

(d) measuring their blood pressure, temperature and pulse;
(e) an examination of pupil size under light levels of ambient light, near total darkness and direct light, and an examination of the nasal and oral cavities;
(f) an examination which consists of checking muscle tone and pulse;
(g) a visual examination of their arms, neck, and, if exposed, their legs, for evidence of injection sites.

After this last set of tests are completed, a decision will be made whether the driver of the car will be charged under the Criminal Code with driving while impaired by alcohol or drugs.

If the Drug Recognition Expert forms the opinion that an individual was operating a motor vehicle while impaired by a drug, they may also demand that the driver provide a sample of their bodily fluid, such as saliva, urine or blood, so that a toxicologist can test the sample and provide a report.

Legal Implications of the Drug Recognition Evaluation Process

Despite the complex evaluation process, the opinion of a Drug Recognition Expert is still extremely subjective and not conclusive in any way to the ultimate issue of whether an accused was driving a vehicle while impaired by a drug. This evidence of a Drug Recognition Expert can often be undermined in court through skillful cross-examination based on their qualifications, whether testing was done improperly, the unreliable nature of test results, or contradictory evidence.

Even when Drug Recognition Experts order toxicology reports of bodily fluid samples, courts have noted the limitations of such reports. For instance, some drugs remain in the body for a longer period of time, making it difficult to determine the time of consumption. A recent investigation by a former judge of the Ontario Court of Appeal, the Honorable Susan E. Lang, found that hair-strand drug testing used at the Motherisk Drug Testing Laboratory, whose reports were relied on in criminal proceedings, were inadequate and unreliable. In other words, many innocent people were falsely found to have been using drugs.

It is therefore important to be vigilant about the use of “expert” evidence in cases that allege the accused was driving while impaired. The experience, competence and knowledge of the law by a defence lawyer can make all the difference between a conviction and an acquittal.


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