In the 2015 Speech from the Throne, the Government of Canada expressed its commitment to legalize the possession, sale, and consumption of marijuana in Canada. With the impending removal of most criminal prohibitions on marijuana usage, it is important to remind those who might wish to partake in this substance of one important criminal offence: the prohibition on drug-impaired driving.  

Section 253(1)(a) of the Criminal Code makes it an offence to operate a motor vehicle, vessel, aircraft, or railway equipment while the person’s ability to do so is impaired by “alcohol or a drug”. The regime for investigating and prosecuting offences of alcohol-impaired driving is well-known: a police officer may use a roadside screening device to investigate whether an individual has alcohol in his or her system, and/or demand that an individual submit to a breath test at the police station. But what happens when you are suspected of driving under the influence of drugs?

There is currently no equivalent mechanism to the roadside screening device or the breathalyzer instrument for testing whether you have a drug in your system, though some preliminary versions of these screening devices are currently being tested in several provinces. Instead, the police rely on a combination of field sobriety tests, observations by a trained Drug Recognition Expert and, usually, scientific analysis of a blood or urine sample.

An investigation will begin when a police officer stops your vehicle. The officer will observe you and assess whether there is a reasonable suspicion that you have a drug in your system and have operated a vehicle, vessel, aircraft, or railway equipment in the prior three hours. The police officer need not suspect your ability to drive is impaired by a drug — he or she must simply suspect you have a drug in your system. In the case of marijuana, the smell of marijuana in the car may be enough.

The police officer could decide he or she already has those reasonable and probable grounds, arrest you for impaired driving, and require you to submit to an evaluation by a Drug Recognition Expert.

If at this point, the police officer does not feel he or she has reasonable and probable grounds they can then require you to perform physical coordination tests for the purpose of determining whether he or she has reasonable and probable grounds to believe your ability to drive is impaired by a drug.

The roadside physical coordination tests are administered by a police officer who is trained in administering them. The Criminal Code sets out three tests the officer must administer:

                1) the “horizontal gaze nystagmus” test;

                2) the “one-leg stand” test; and

                3) the “walk-and-turn” test.

For the first test, the police officer will ask you to follow an object with your eyes, such as a pen. The police officer will move the object from side to side, observing whether your eyes follow the object smoothly or whether they show any involuntary “jerking” movements.

For the second test, the police officer will ask you to stand on one leg and count out loud, usually about 30 seconds. The police officer will observe your balance.

For the third test, the police officer will ask you to take approximately 9 steps in a line, heel to toe. He or she will then ask you to turn on one foot and return along the line in the opposite direction. The police officer will observe your ability to follow directions, the manner in which you walk, and your balance during the test. Based on the officer’s observations of all of these tests, along with any other relevant observations the officer has made, the officer will determine whether he or she has grounds to arrest you for driving while your ability to do so was impaired by a drug.

At this point, it is not sufficient for the officer to simply believe you have a drug in your body. The officer must believe you have a drug in your body and your ability to drive is impaired by that drug. However, the officer is not required to have any specific belief about what particular drug you have in your system.  The officer must subjectively believe your ability to drive is impaired by a drug, and that belief must be objectively reasonable in the circumstances.

If you are placed under arrest, the police officer has an obligation to tell you what you were arrested for. The officer must also give you the opportunity to contact a lawyer. Once you have consulted a lawyer, made sufficient attempts to do so, or declined to contact a lawyer, you will be asked to submit to an evaluation conducted by a Drug Recognition Expert.

A Drug Recognition Expert is a police officer who is specifically trained and certified in administering and evaluating indicia of drug impairment. The Drug Recognition Expert will perform twelve evaluations: eye evaluations, including a more extensive version of the horizontal gaze nystagmus test; divided-attention tests, such as the one-leg stand and walk-and-turn tests; an examination of your blood pressure, temperature, and pulse; an examination of your pupils, nose and mouth; an examination of your muscle tone and pulse; and a visual examination of your arms, neck, and potentially your legs, looking for injection sites. Based on this evaluation, the Drug Recognition Expert will form an opinion as to whether your ability to drive is impaired by a drug. If the Drug Recognition Expert believes your ability to drive is impaired by a drug, he or she may require you to provide a saliva, urine, or blood sample. That sample will be sent for toxicological analysis, which will show what drugs are in your system (if any).

What does all of this mean? First, legalizing previously prohibited drugs like marijuana does not mean everything related to the use of this drug is now legal. Those who choose to use this substance must realize they still could face criminal prosecution and conviction if they choose to drive under the influence of marijuana.. Second, it does not matter whether you use a drug legally or illegally – if your ability to drive is impaired by any drug, including those legally prescribed to you, you could face criminal prosecution and conviction. Any drug that affects your perception, coordination, or motor skills could impair your ability to drive. Third, if you are stopped and arrested on the belief that your ability to drive is impaired by drugs, you should contact a lawyer who is familiar with this legislation and can advise you on what to expect during the evaluation process and what your rights and obligations are.   

If you are arrested for, or charged with, a drug-impaired driving offence, or you are simply interested in more information on the topic, please contact any lawyer in the McDougall Gauley LLP criminal law practice group for assistance. 

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