Canada: Medical Marijuana: If You Can't Measure Residual Impairment, You Can't Manage Risk – And In A Safety Sensitive Position, That's Undue Hardship In Re Lower Churchill Transmission Construction Employers' Assn. Inc. And IBEW, Local 1620 (Tizzard)

Last Updated: June 11 2018
Article by Darren Stratton

Co-authored by Andrea Williams, Articled Clerk at McInnes Cooper

As the target date for the legalization of recreational cannabis in Canada draws near, employers are feeling the heat to prepare for the workplace implications of recreational cannabis use. But the workplace impact of medically-authorized marijuana use is already a burning issue for employers. A key challenge they face is the accommodation of medically-authorized marijuana use by employees in safety-sensitive positions. On April 30, 2018, a N.L. Arbitrator decided that since employers can't measure residual impairment caused by cannabis use, they can't manage the safety risk – and in a safety-sensitive position, that amounts to undue hardship on the employer. Here's a look at the Arbitration decision in Re Lower Churchill Transmission Construction Employers' Assn. Inc. and IBEW, Local 1620 (Tizzard), and five key highlights of the decision that help employers deal with the accommodation of medically-authorized marijuana in the workplace.

The Arbitration Decision

Mr. Tizzard (the Grievor) was diagnosed with Crohn's disease and osteoarthritis. After several unsuccessful attempts to alleviate the resulting pain with conventional medications, his physician issued him a Medical Authorization for up to 1.5 grams of cannabis with THC levels up to 22%, to be ingested by vaporization. The Grievor said he ingested the marijuana every evening but didn't feel impairment of function during daytime working hours. He subsequently applied for two labourer positions with the employer, a major contractor working on one of the Lower Churchill Projects (the construction of transmission lines), and the employer hired him – subject to the pre-employment drug and alcohol screening tests. The Grievor disclosed his medical marijuana use to the Union before the testing, and to the sample collection technician at the time of testing, which he failed. After obtaining and reviewing a significant amount of medical information, the employer ultimately refused to hire the Grievor for either position.

The Union grieved, alleging the employer failed to accommodate the Grievor's disability. The employer argued that given the inability to test for cannabis impairment and the safety sensitive nature of the positions, accommodation of the Grievor would amount to undue hardship. Newfoundland and Labrador Arbitrator John Roil, QC, after thorough review and analysis, succinctly agreed (at page 65):

"The [e]mployer did not place the Grievor in employment at the [p]roject because of the Grievor's authorized use of medical cannabis as directed by his physician [evening use of up to 1.5 grams of medical marijuana with THC levels up to 22% ingested by vaporization]. This use created a risk of the Grievor's impairment on the jobsite. The [e]mployer was unable to readily measure impairment from cannabis, based on currently available technology and resources. Consequently, the inability to measure and manage that risk of harm constitutes undue hardship for the [e]mployer."

McInnes Cooper Labour & Employment Lawyer Darren Stratton represented the successful employer in the Arbitration.

5 Key High-lights

Although no court nor any other arbitrator is required to follow this Arbitration decision, it's likely to be of interest and potentially persuasive value in other cases. There are relatively few reported decisions in Canada on the issues of either the accommodation of medically-authorized marijuana use by someone in a safety-sensitive position, or just what qualifies as a safety-sensitive position. And it's likely to be an issue with which employers will grapple more often. Data suggests the number of Canadians with a medical authorization – presumably many of whom are employees – is on the rise. For example, according to Statistics Canada numbers, between the end of April 2017 and the end of December 2017 the number of active client registrations for cannabis for medical purposes with licensed producers grew from 174,503 to 269,502 – an increase of 54% (astounding even bearing in mind individuals can be registered with more than one producer if they've provided an original medical document with each registration, but can also be registered with Health Canada to produce or designate someone to produce for them a limited amount of cannabis for their own medical purposes). Yet, as the Arbitrator's decision acknowledges throughout, employers are still trying to understand how to manage the impact of medically-authorized marijuana use in the workplace.

Here are five key highlights of the decision that help employers deal with the accommodation of medically-authorized marijuana in the workplace:

1. The duty to accommodate disability to the point of undue hardship extends to accommodation of medically-authorized cannabis use.

Under human rights laws, employers have a duty not to discriminate in employment (including hiring decisions) on the basis of the "protected" personal characteristics enumerated in the applicable human rights law. These characteristics differ somewhat depending on the human rights law that applies (for example family status, sexual orientation, religion, and mental disability), but all Canadian human rights laws prohibit discrimination based on physical disability. Embedded in this discrimination prohibition is the employer's duty to accommodate an employee's (or applicant's) protected personal characteristic to the point of undue hardship: to take steps to offset the discriminatory impact of a workplace rule, policy, requirement or practice by adjusting, revising, or eliminating it.

It might go without saying, but it's worth repeating: this duty to accommodate disability includes the duty to accommodate medically-authorized marijuana used as a treatment for a disability. In this decision, the Arbitrator accepted with little discussion that the Grievor's disability was both his medical condition and its treatment by use of medical cannabis and the entirety of the dispute was about the employer's ability to accommodate not the symptoms the Grievor suffered from his diagnosed medical condition, but the effects of the chosen treatment (medically-authorized marijuana) for those symptoms.

2. The duty to accommodate also applies to safety-sensitive positions – but not every position in a safety-sensitive enterprise is safety-sensitive.

Designation of a position or, as in this case, a category of positions, as safety-sensitive does not relieve the employer from the duty to accommodate – but it's still important because it informs the undue hardship analysis and helps define the medical information the employer reasonably needs for the accommodation process.

Just because an enterprise is in an industry designated as inherently safety sensitive does not mean that every position in that enterprise is a safety sensitive one. As the Arbitrator in this case noted, the designation of workplaces or positions as safety-sensitive serve different purposes. There aren't many reported decisions available to help employers ascertain whether a position is safety-sensitive. However, those that are available indicate that a safety-sensitive position is one in which the employee has a key and direct role in an operation where performance affected by substance use: could result in a significant incident, near miss, or failure to adequately respond to a significant incident; and detrimentally affect any of the health, safety or security of the employee, other people, property, the environment or the employer's reputation.

In this case, the Arbitrator didn't discuss the legal test for a safety-sensitive position in detail but he did conclude that both labourer positions for which the Grievor had applied, and "every labour job function" at the employer's project sites, is safety-sensitive. The Arbitrator's conclusion illustrates how an employer can prove a position is safety-sensitive:

Choose the right witness. Evidence from a person in the enterprise who is intimately familiar with the conditions in the work environment and with the daily activities of the position in question is critical. In this case, the Arbitrator seemed to place significant weight on the evidence of the employer's project safety advisor and supervisor, who was responsible for occupational health and safety law compliance, in deciding all labour functions on the project sites are safety-sensitive.

Present details of the activities of the position and their associated risks to the employee – and to other workers. The chosen witness should be able to detail the tasks the person in the position must carry out and the demands it makes on employees, including the mental, physical and, where relevant, geographic conditions under which the employee in the position must work and the safety risks to which the position exposes the employee – and others. In this case, the evidence of the proximity of not just the Grievor, but also other workers, to the workplace hazards was important: the safety issues associated with the Grievor's cannabis use weren't limited to the Grievor; they extended to other workers too.

Use aids to help illustrate the risks. Consider and utilize aids to help the Arbitrator understand the demands and risks of the position. In this case, the Arbitrator expressly referred to photographs showing the range of typical conditions under which the person in the position must work (in this case, the "harsh terrain and the wide variety of weather conditions"). The safety advisor had also calculated and presented to the Arbitrator statistics of site injuries and their causes.

3. Residual cannabis impairment might last for more than 24 hours – and right now, employers can't measure it.

The Arbitrator accepted without hesitation that THC (delta-9-tetrahydrocannabinol, which has therapeutic effects but is primarily responsible for cannabis's psychoactive effects), causes impairment. The big question was just how long this impairment might last and how to accurately measure it – and on these points there is still uncertainty in the medical and scientific communities. The Arbitrator's conclusions on this point are significant and clear; and while the Arbitrator appears to limit the conclusions to "medically authorized cannabis products", it would seem they are equally applicable to recreational cannabis use:

Residual impairment from cannabis use can last more than 24 hours. The Arbitrator concluded that regular use of medically authorized marijuana can cause impairment that can last up to 24 hours after consumption. While acknowledging research is ongoing, the Arbitrator based this conclusion on what he characterized as the three "Guidance documents" offering currently available advice to physicians:

  • Health Canada's 2013 Information for Health Care Professionals.
  • The College of Family Physicians of Canada's 2014 Preliminary Guidance on Authorizing Dried Cannabis for Chronic Pain and Anxiety.
  • The N.L. College of Physicians and Surgeons' 2014 Advisory to the Profession and Interim Guidelines – Marijuana for Medical Purposes.

There is no impairment testing method readily available for employers. The Arbitrator expressly concluded there are no readily available testing resources in N.L. allowing an employer to "adequately and accurately measure impairment arising from cannabis use on a daily or other regular basis". Although the Arbitrator did limit this conclusion to resources available in N.L., since two of the three "Guidance documents" he relied upon are national in scope (and the third provincial document referenced back to one of the national ones), arguably the same conclusion should apply elsewhere in Canada – absent evidence to the contrary.

Users' self-reports of impairment from cannabis are not reliable. The Arbitrator effectively concluded that even if a worker who uses cannabis says they don't feel high and believes they aren't impaired, they might in fact still be impaired: a consequence of the cannabis use itself can be lack of awareness about their own functional impairment. Although the Arbitrator didn't expressly say so, this also implies that "medical reports" or doctor's notes based on the worker's self-reports about whether or not they "feel" or "believe" they are impaired are also of questionable reliability.

4. Employers' inability to measure impairment makes them unable to manage safety risks – and that is undue hardship.

The employer's duty is to accommodate an employee's disability to the point of "undue hardship". To fulfill it, the employer must undertake an individual assessment of the employee, and identify and evaluate the options to accommodate them. Ultimately, the employer must either select and implement an option, or demonstrate the discrimination is justified because it's based on a "bona fide occupational requirement" (a.k.a. "BFOR", "bona fide occupational qualification" or "genuine occupational requirement") and the employer either:

  • Cannot accommodate the employee at all without experiencing undue hardship.
  • Has accommodated the employee to the point where further accommodation will result in undue hardship to the employer.

The law thus requires employers to suffer some hardship – just not an "undue" amount. And the bar is high. Several factors are relevant to quantifying the hardship level, including: financial cost relative to the employer's size; disruption of a collective agreement; problems of morale of other employees; the interchangeability of the workforce; the adaptability of facilities; and the magnitude of any safety risks and the identity of those who bear them.

This case was all about safety risks: if the employer can't measure cannabis impairment, then it can't manage the risk of harm arising from it. The Arbitrator accepted that with current technology and resources, an employer can't accurately measure impairment from cannabis. This inability to measure impairment created a risk of harm the employer couldn't readily mitigate – and this unacceptable increased safety risk amounted to undue hardship on the employer.

Designation of a position(s) as safety-sensitive informs the undue hardship analysis. The designation of a positon as safety-sensitive does not relieve the employer from accommodating the employee – but it does inform the undue hardship analysis. In this case, the Arbitrator decided that since both positions for which the employee applied are safety-sensitive, the BFOR for the purposes of the undue hardship analysis was that a labourer must be able to "perform work in a safe manner". The Arbitrator confirmed that in the accommodation process, the assumption of "some" safety risk (i.e., hardship) is acceptable – but not an "undue" safety risk. He accepted the evidence of an occupational health and disability management expert that due to lack of available monitoring, the inability to accurately measure the extent of daily impairment is a legitimate concern when employing a person using medically-authorized cannabis in a safety-sensitive position. And since neither the union nor the employer presented any evidence of any available, non-safety-sensitive positions as an accommodation option, it came down to an "all or nothing" scenario: accommodation in the safety-sensitive positions for which the Grievor applied, or no position at all.

Safety first – now. Key to the Arbitrator's undue hardship analysis were the uncertainty in the medical and scientific communities around cannabis impairment and the Arbitrator's acceptance that, based on current technology and resources, an employer cannot accurately measure impairment from cannabis. The Arbitrator expressly confirmed "[a]n employer cannot make hiring decisions simply based on information from clinical studies." Acknowledging the employer's legal duty under occupational health and safety laws to provide a "safe" workplace, and specifically to prohibit impaired workers, the Arbitrator concluded the employer should not be required to employ them. The decision implicitly accepts that an employer's obligation under occupational health and safety laws to reduce its risk and create a safe work environment can't await scientific certainty: employers should take a precautionary approach to maintaining a safe work environment – and must do so based on the best information available at the time.

Alcohol is different than cannabis. As the Arbitrator implicitly acknowledged in this decision, the relationship between alcohol consumption and impairment are better understood, and employers do have reliable methods to measure current impairment due to alcohol. However, it is this inability to test for impairment (including residual impairment) from marijuana that distinguishes the accommodation of marijuana from the accommodation of alcohol. Therefore, an employer could still be required to accommodate an employee with an alcohol-related disability in a safety-sensitive position depending, of course, on the particular situation.

5. Complete – and specialized – medical information is a must to accommodate medically-authorized marijuana use.

Generally speaking, the employer's duty to accommodate obligates it to individually assess the work options that might be available to the particular employee in the circumstances. To do so in the case of accommodation of a disability, the employer is entitled to sufficient medical information to determine whether and how the employee can safely work. Generally, to fulfill its duty to accommodate the employer is entitled to know:

  • The general nature of the illness and how it manifests as a disability.
  • Whether the disability is permanent or temporary and the anticipated timeframe for improvement.
  • The restrictions or limitations that flow from the disability, particularly as they relate to the employee's duties.
  • The basis for the medical conclusion (though not test results or clinical notes).
  • The treatment and medications (side effects) that may affect the employee's ability to perform her job.

If there are reasonable grounds to do so, however, the employer could be entitled to require the employee to produce additional medical information or obtain a second medical opinion to support an accommodation request. And in this case, the employer did just that – more than once.

Safety-sensitive designation helps define the medical information to which the employer is entitled. Employers need not – and should not – accept a brief Medical Authorization for medical marijuana written on a prescription pad: it is entitled to more, especially when dealing with a treatment the effects of which are surrounded by such great uncertainty. In this case, the Arbitrator agreed with the employer that the Grievor's initial medical report didn't contain enough information for it to determine whether the Grievor could perform the jobs for which he applied in a safe manner (the BFOR in this case). The initial report confirmed the Grievor was taking medical marijuana, it was evening use only, included the physician's recommendation of a four-hour driving restriction, and advised of the physician's lack of concern about his daytime function – but provided no dosage details. The employer was persistent in seeking more medical information about the extent to which medical marijuana use would impact workplace safety.

Specialized training is required to understand work restrictions due to cannabis impairment. The Arbitrator expressly concluded that a full understanding of the interaction between marijuana impairment and appropriate work restrictions in a particular case requires specialized training – and a general practitioner can't determine the safety issues in a hazardous workplace based only on examining the patient and a basic understanding of their work. The Arbitrator effectively rejected the Grievor's physician's evidence that she didn't "feel" the Grievor's level of impairment the day after his marijuana use would affect his job performance, and he could work safely on a daily basis in a safety sensitive-position – despite acknowledging the possibility of "some residual impairment" after use – given her limited understanding of the Grievor's worksite demands and relatively lower understanding of the long-term impacts of inhalation of relatively higher THC-content cannabis.

Expert advice & evidence. The law doesn't expect employers to be medical experts – particularly where, as here, the employer is dealing with an "emerging" area of concern. In this case, the employer retained an independent medical consultant to advise it on the impact of cannabis use on workplace safety and the medical information it required in the accommodation process. And if the issue goes to a hearing, employers should be prepared to present extensive expert evidence. In this case, it was critical in persuading the Arbitrator of both the impairing effects of cannabis and the inability to measure those effects – and ultimately of undue hardship on the employer.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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