Are supervisors able to assess impairment? Drug driving decision suggests so


A recent Ontario decision suggests that laypersons - such as supervisors – may assess whether a person is impaired from drugs or alcohol, and their assessment will be considered in legal proceedings.

In a “drug driving” case, a driver was found guilty of driving while impaired by marijuana.   A police officer approached his vehicle and observed him as having bloodshot, glassy eyes and the smell of marijuana was coming from the vehicle.  The driver’s pupils were dilated. The driver admitted to having smoked a “J” approximately 2 1/2 hours earlier.  He was taken to a police station where another officer, a “drug recognition evaluator”, observed him and performed certain physical and other tests, and concluded that he was impaired.

The driver argued, on appeal, that the drug recognition evaluator should not have been accepted by the trial judge as an “expert” witness on drug recognition.  The appeal court disagreed, going on to state that the courts have had a long-accepted practice of admitting evidence of non-expert witnesses about whether a person was intoxicated or impaired.

Interestingly, a urine test came back negative for THC, the active ingredient in marijuana that causes physical impairment, but the court still decided that based on the police officers’ observations and assessments, the driver was impaired when he was driving (even if he was no longer impaired when the urine sample was taken).

The appeal court referenced the Evaluation of Impaired Operation (Drugs and Alcohol) Regulations, which are used by police officers who are “certified drug recognition experts” to evaluate whether a driver is impaired by drugs or alcohol. Those Regulations set out a number of tests that those officers can perform to assess whether the person is impaired.

Supervisors often question whether they have the expertise to assess whether an employee is impaired. This decision suggests that supervisors’ observations are important and will be relevant evidence in legal proceedings, such as a wrongful dismissal action by an employee who was dismissed for being impaired at work.  Supervisors tasked with identifying impairment should, preferably, be given training and materials (such as a checklist) to help them in the task.

R. v. Henry, 2014 ONSC 4115 (CanLII)

DISCLAIMER: Because of the generality of this update, the information provided herein may not be applicable in all situations and should not be acted upon without specific legal advice based on particular situations.

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