On December 13, 2016, the Government of Canada released A Framework for the Legalization and Regulation of Cannabis in Canada: The Final Report of the Task Force on Cannabis Legalization and Regulation (“Report”). The Report's primary focus was not workplace safety - a little over one page (pages 28-29) of the 106-page report was dedicated to that.

The Report’s discussion of the issues associated with determining cannabis impairment is, however, of interest to those employers who have, or are considering implementing, a workplace drug testing policy.

Workplace Safety Recommendations

The Report’s Workplace Safety section recognizes the dangers of an impaired employee, particularly those in safety-sensitive industries. Despite noting that “employer groups called for more guidance from federal, provincial and territorial governments about appropriate workplace drug use and drug testing policies…”, the Report did not recommend such legislative guidance.

The Report noted a lack of research to “reliably determine when individuals are impaired” and that the "ability to determine impairment with cannabis … is not as advanced as our ability to measure the relationship between consumption and impairment with alcohol..." The Report said that if “new evidence on cannabis impairment merit changes in workplace safety policies,” the federal governments should work closely with the provincial governments to “consider and respond to the implications of this evidence.”

The Workplace Safety Recommendations called for ongoing research on cannabis and impairment and for governmental, employer and labour representatives to work together to facilitate the development of workplace impairment policies.

Impairment

Employers will likely be most interested in the discussion of impairment in the Report’s Impaired Driving section.

From an employer’s perspective, the Report makes the following positive conclusions:

  • “It is clear that cannabis impairs psychomotor skills and judgment".  
  • “…there is a link between cannabis use and decreased driving performance and increased crash risk”.  
  • a per se limit for THC (i.e., “a level deemed to be consistent with significant psychomotor impairment and increased risk of crash involvement”) "would simplify enforcement and adjudication by eliminating the need to prove, on a case-by-case basis, that a driver was impaired..." Although the Report refers to per se limit for THC blood levels (as opposed to oral or urine levels, which are the common bodily fluids tested in a workplace drug testing policy), the Report’s recognition of a clearly defined standard is positive.  
  • "...oral fluid screening devices are the most advanced today (and have the added advantage of signaling recent use)..."  
  • "there is currently no evidence to suggest there is an amount of THC that can be consumed such that it remains safe to drive..."

However employers should be aware of the challenges that the Report notes in determining cannabis impairment which employees and unions may use to challenge drug testing. They include:

  • "cannabis-impaired driving is more complex to study than alcohol-impaired driving;"  
  • although there is scientific agreement that "THC impairs driving performance, the level of THC in bodily fluids cannot be used to reliably indicate the degree of impairment or crash risk";  
  • unlike alcohol "THC can remain in the brain and body of chronic, heavy users of cannabis for prolonged periods of time (sometimes several days or weeks), far beyond the period of acute impairment, potentially contributing to a level of chronic impairment…"  
  • "Some heavy, regular users of cannabis, including those who use cannabis for medical purposes, may not show any obvious signs of impairment even with significant THC concentrations in their blood. Conversely, infrequent users with the same or lower THC concentrations may demonstrate more significant impairment."  
  • “Other challenges exist, including the need to account for the rapid and sharp decline of THC levels in the blood in the hours following consumption through smoking (with edibles the decline is more gradual).”

Significance

Any employer concerns regarding the Report’s suggestion that there is a need for further scientific evidence to determine a per se limit must be considered in the following context:

  1. The Report overwhelmingly reinforces the inherent dangers of cannabis impairment in the workplace and when operating a motorized vehicle.
  2. The Report emphasizes the importance of a clearly defined standard of impairment so as to avoid adjudication. This is particularly important in the employment context given that it would be untenable to have an undefined standard.
  3. Given the significant penal consequences that result from an impaired driving conviction and the higher standard of proof (beyond a reasonable doubt) under the Criminal Code of Canada, a per se limit is more important in the criminal law context. Such legal considerations are not generally present in the context of a violation of a workplace drug testing policy.
  4. One of the leading workplace drug testing decisions, Imperial Oil (2006), a decision that was affirmed by the Ontario Court of Appeal and was most recently endorsed by the Supreme Court of Canada in Irving Pulp and Paper found that oral fluid testing did disclose cannabis impairment: “The drug test is by means of a buccal swab which is used to identify only impairment by the use of cannabis, utilizing the cutoff point of 10 nanograms per millilitre of blood. It is not contested that the results of the oral fluid drug tests do disclose impairment by the use of cannabinoids.”