Employees on drugs: fitness for duty and burden of proof

Who is to say whether an employee is fit for duty? Does the employee have to prove they are, or does the employer have to prove they’re not? Where technology does not necessarily exist such as would allow an employer to definitively prove an employee is not fit for duty, is the employee simply presumed to be unimpaired – despite recent and/or ongoing drug use? Perhaps a different balancing of interests is required?

A recent Quebec arbitration decision, Syndicat Canadien de la Fonction Publique Section Locale 4041 v. Air Transat (Air Transat), 2026 CanLII 44306, confirms that employers may prohibit employees in safety-sensitive positions from consuming drugs, even on their days off, where justified by workplace safety concerns. The decision reflects a willingness of decision-makers to prioritize safety over employee privacy and autonomy where the two are in conflict – so far as they may relate to an employee’s consumption of recreational (or medicinal) narcotics.

Air Transat, a Montreal-based airline, implemented a workplace policy prohibiting employees in high-risk positions from consuming any type of drug, whether legal or illegal, at any time (the Policy). Unionized employees, including flight managers, flight attendants and trainers (the Cabin Crew), were classified as high-risk positions under the Policy.

Air Transat implemented the Policy out of concern for the safety of the cabin crew and air passengers in the wake of the legalization of marijuana in October 2018.

Safety versus privacy

The Policy at issue activated two competing interests: The employer’s obligation to ensure the safety and security of their employees and the public, and the employees’ rights to privacy and personal autonomy. Accordingly, the arbitrator framed the issue as whether the infringement on employees’ privacy rights was justified, proportionate and minimally infringing in light of the Policy’s objectives.

The tribunal acknowledged that an employer may adopt policies aimed at defining and regulating the work done by employees. However, the exercise of this right is subject to conditions. In assessing the validity of a policy imposed unilaterally by the employer, the criteria from Re Lumber & Sawmill Worker's Union, Local 2537, and KVP Co. Ltd., (1965), 16 LAC 73 must be considered.

This framework requires an evaluation of the compatibility of the impugned policy with the applicable collective agreement and an assessment of the reasonableness of the policy itself. The assessment of reasonableness requires arbitrators to utilize their expertise, consider all circumstances, and determine whether the policy strikes a reasonable balance of interests between the parties involved. As the Supreme Court of Canada has affirmed, employer policies that intrude upon employee privacy must be justified by a demonstrable need that outweighs their adverse impact on employee rights.

Although the right to privacy is not explicitly outlined in the Canadian Human Rights Act; it is enshrined in Quebec law through the Charter of Human Rights and Freedoms and the Civil Code of Quebec. In assessing whether the Policy breached the right to privacy, the employer was required to demonstrate that the Policy was pursuing a legitimate and important objective, that any infringement was proportionate to the objective and that the infringement of the protected right was minimal.

The arbitrator emphasized that privacy rights, while significant, are not absolute. In certain circumstances, it is not unlawful for an employer to infringe upon such rights, particularly where danger exists in the work environment.

Proof of risk from cannabis use lacking: union

CUPE argued the policy constituted an unjustified and unreasonable exercise of the employer’s management rights and that prohibiting cannabis use infringes on flight attendants’ rights to privacy and autonomy, fails to consider the nature of duties performed by flight attendants and is inconsistent with current scientific knowledge. In particular, CUPE alleged that Air Transat had not established that the residual effects of cannabis increase the risk of an incident or render flight attendants unfit to perform their duties. In essence, CUPE argued that the employer could not prove the flight attendants were unfit for duty as a result of their consumption of cannabis during their time away from work.

Air Transat, in contrast, maintained that the Policy was necessary to uphold the safety of its operations and those involved. Even if the Policy infringed on privacy rights, Air Transat argued any infringement was minimal and justified. As a company in the aviation sector, it emphasized its obligation to ensure passenger and employee safety and protect its reputation.

The tribunal considered the strenuous training undertaken by flight attendants, the tasks and responsibilities of cabin crew and expert evidence retained by both parties in determining whether the Policy is reasonable and valid.

The employer is a pursuing a legitimate and important objective

The arbitrator agreed that Air Transat’s obligation to guarantee the safety of all passengers and employees on board an aircraft was both a legitimate and important objective. Expert evidence presented a general consensus that cannabis use can impair an individual’s reaction time, judgement, short-term memory, decision-making skills and concentration. The nature of the aviation industry requires employees to be at full capacity and thus justifies the employer regulating the use of cannabis outside of working hours.

The Policy is proportionate to the objective pursued

Although the Policy did infringe on flight attendants’ right to privacy and personal autonomy, the tribunal found this infringement proportionate to the objective of safety. They relied on the variability in the effects of cannabis among individuals and the lack of reliable screening tools to assess a person’s functional capacity to justify imposing the Policy to ensure full capacity of flight attendants. The fact that impairment could not be proven or guaranteed was not a bar to the Policy. To the contrary, the technological limitations on establishing impairment through marijuana use supported the employer’s position given the importance of the other interests being protected.

The infringement on the right to privacy is minimal

Lastly, the tribunal concluded that the Policy minimally infringed on flight attendants’ right to privacy. The degree of intrusion depends on the activity in question, and while case law has characterized random drug screenings as intrusive, the arbitrator found being prevented from consuming cannabis does not amount to the same level of intrusion.

Privacy infringement proportionate to safety objective in safety-sensitive workplace

The tribunal dismissed CUPE’s grievance, upholding the validity of Air Transat’s Policy. Despite a lack of clear evidence on the length of impairment and variability in the effects of cannabis, the arbitrator found the objective of ensuring safety on aircrafts is necessary and proportionate to the infringement of privacy. The arbitrator suggested that a time standard could eventually be implemented by Air Transat. However, this would require more conclusive research on the residual effects of cannabis.

The Air Transat decision highlights an important trend in Canadian law to the effect that employers operating safety-sensitive workplaces may not have to definitively prove employees are impaired in order to take action through the implementation of anti-drug or fit-for-duty policies. The limitations which currently exist with respect to testing impairment levels arising from marijuana use have not been permitted to excuse off-duty use of marijuana in safety-sensitive workplaces. To the contrary, as we see in the Air Transat decision, there is acceptance that assuring the safety of employees and the public will outweigh the infringement experienced by employees who might otherwise wish to partake in their personal time away from work.

Tye Hapke is an associate in the labour and employment group at MLT Aikins in Saskatoon. Robert Frost-Hinz is a partner in the labour and employment department at MLT Aikins in Saskatoon.