Alberta Court Confirms Legal Test for Assessing Appropriateness of Post-Incident Drug and Alcohol Testing

April 20, 2018 | Sheena Owens

Think alcohol and drug testing is always an appropriate response to a workplace accident? Think again. The Alberta Court of Queen’s Bench recently affirmed that, in order for an employer to justify drug and alcohol testing, there must be a connection between the incident and the employee’s involvement such that the employee is the root cause of the accident.

Background Facts

In Canadian Energy Workers’ Association v. ATCO Electric Ltd., two ATCO Electric Ltd. (“ATCO”) employees underwent drug and alcohol tests following a low-speed collision between a Nodwell and a pick-up truck. The Nodwell was backed into a company pick-up truck when it was previously understood the Nodwell was going to be driven in a forward direction. There were no injuries arising from the accident and no lost time. The accident was reported to the employees’ supervisor who conferred with his supervisor and ultimately decided to have the employees tested for drugs and alcohol under ATCO’s alcohol and drug policy (the “Policy”). One employee screened positive for cannabis and the other was negative for all substances. The positive employee eventually went through a treatment program and returned to work without incident. Ultimately, the damage to property was only about $1,000 and the immediate cause of the accident was found to be failure to use a spotter in a congested area and poor employee judgment of distance. The Union grieved the post-incident testing arguing it was an inappropriate application of the Policy. The Arbitration Board dismissed the grievance and the Union sought judicial review of that dismissal.

The Alcohol and Drug Policy

The Policy required mandatory post-incident drug and alcohol testing under a variety of scenarios, including when: (1) the incident would cause lost time, regardless of the amount of time lost; (2) the incident was reportable or likely to be reportable under the Occupational Health and Safety Act, for example, involving a serious injury, hospitalization of a worker, or a fatality, amongst other things; (3) the incident resulted in property damage over $10,000; or (4) there was compelling evidence that the acts or omissions of any employees involved in the incident contributed to the incident. The only exception to mandatory testing was when there was clear and unequivocal evidence that the acts or omission of an employee was not a contributing factor to the incident.

The Policy also contained a discretionary provision to conduct post-incident testing: “for all other significant work related incidents, the supervisor investigating the incident may arrange to have a drug and alcohol test done on the worker (or workers) involved…in an incident which local management determines…could have resulted in lost time [and other criteria].” In this case, the post-incident testing occurred under the discretionary provisions of the Policy as there was the potential for injury, lost time, and property damage over $10,000.

Arbitration Award

The grievance did not challenge the Policy, but instead challenged ATCO’s application of the Policy based on the facts at hand. The Arbitration Board relied on the leading Alberta arbitration decision, Weyerhaeuser (Roberto Grievance), in rendering its decision. In that case, the arbitrator found that employees should not be automatically sent for testing following an accident. Instead, there had to be a connection between the employee and the accident to justify the testing.  Ultimately, in this case, the Arbitration Board found that the testing was justified because the employees should have been aware of the need for a spotter when moving the Nodwell, they were aware of the limited visibility off the Nodwell, and that poor judgment or mistaken assumptions were the root cause of the accident. The Union sought judicial review of this decision.

Court of Queen’s Bench Decision

The Court reiterated that employees do not give up privacy rights when they enter the workplace. Therefore, when assessing the appropriateness of post-incident drug and alcohol testing, the employee’s privacy rights and bodily integrity must be balanced with the employer’s interest in maintaining a safe workplace. The Court summarized and adopted the principles in Weyerhaeuser (Roberto Grievance) to assess the appropriateness of post-incident testing including: (1) the threshold level of the incident needed to justify the testing; (2) the degree of inquiry necessary before the decision to test is made; and (3) the necessary link between the incident and the employee’s situation to justify testing.

The Court held that an accident alone is an insufficient basis to intrude on an employee’s privacy rights and order post-incident testing. The employee must be the root cause of the accident. In this case, the Court noted the employees had been properly trained about operating Nodwells and that the investigation established the employees’ lack of judgment was the cause of the accident. As such, there was evidence to support an inquiry as to whether alcohol and drugs had played a part in the employees’ lack of judgment and error. The application for judicial review was ultimately denied.

Lessons to Be Learned

Although this case is a positive outcome for employers operating in Alberta, it reiterates the need to conduct a detailed analysis as to whether post-incident testing is justified. Not every workplace accident will warrant employee drug and alcohol testing. Employers must be able to establish that there is a connection between the accident and the employee who may be subjected to the drug and alcohol testing. Accidents without a link between the incident and the employee are insufficient to justify submitting an employee to testing. To best protect themselves from grievances and privacy complaints, employers across Canada should ensure that they have written drug and alcohol policies in place and that those are in line with the ever-developing case law in this area in their respective jurisdictions.


This publication is provided as an information service and may include items reported from other sources. We do not warrant its accuracy. This information is not meant as legal opinion or advice.

Miller Thomson LLP uses your contact information to send you information electronically on legal topics, seminars, and firm events that may be of interest to you. If you have any questions about our information practices or obligations under Canada's anti-spam laws, please contact us at

© 2022 Miller Thomson LLP. This publication may be reproduced and distributed in its entirety provided no alterations are made to the form or content. Any other form of reproduction or distribution requires the prior written consent of Miller Thomson LLP which may be requested by contacting