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Navigating the numerous complications of managing marijuana use in the workplace

Several major societal trends are converging to make marijuana in the workplace one of the biggest challenges facing Canadian employers.

Several major societal trends are converging to make marijuana in the workplace one of the biggest challenges facing Canadian employers.

It started with widespread increased tolerance of marijuana consumption and low-level dealing by police in some regions, as well as court rulings upholding the right of patients to grow and use medical marijuana. At the same time, recreational use expanded to a broader age demographic, including “boomers.”

Over the past decade or so, marijuana has emerged as a common treatment for chronic pain, insomnia, anxiety and a number of other diseases, although it is also used for many conditions without solid medical research to back up its medical efficacy. The number of Canadians holding legitimate medical marijuana prescriptions has exploded. Some cities like Vancouver have seen the spread of convenience-store-like marijuana dispensaries where medical marijuana is routinely “prescribed” at the request of the customer for a host of complaints.

Finally, with the election of the federal Liberal government, recreational use of marijuana is slated to become legal under legislation scheduled to be introduced this year and that may come into effect as early as the next 18 to 24 months. Under the schemes being studied, marijuana will be available through government-regulated outlets, much like alcohol.

While no precise figures are available, it seems clear that the cumulative effect of these trends is that more workers are using marijuana. Clearly this poses a challenge for employers who are rightly concerned about marijuana’s effect on workplace safety and productivity. There is ample research to support those concerns indicating marijuana impairs a variety of safety-related mental functions such as reaction times, as well as judgment and other higher-level functions critical to productive and accurate work. Impairment can be due to recent use, “hangover” effects or deficits due to chronic abuse.

There are three scenarios employers might face, each of which comes with its own set of legal rules:

•the recreational marijuana user who uses at work or is impaired by pre-work use while at work;

•the marijuana addict who uses at work or is impaired at work: while doctors consider marijuana to be much less addictive than other drugs such as cocaine, or even nicotine, such addiction (now known by doctors as a “substance abuse disorder”) can occur; and

•the medical marijuana user whose use might create a risk they are impaired at work.

This article will discuss the legal regime applicable to and guidelines for employers in dealing with each case.

Recreational users represent the largest group and impose the least obligation on employers to accommodate their habit. Recreational users are not protected under human rights legislation, and employers consequently enjoy significant latitude to enforce strict rules. Employers can enforce policies that prohibit possession of, dealing in, use of or being impaired by marijuana in the workplace for all workers, including recreational users, with special rules applying to addicts and medical users discussed below.

While a single breach of such a policy by a recreational user might not always be grounds for firing an employee with no other prior discipline history, depending on the risks created, recreational users’ breach of such policies will be grounds for discipline. Where a breach endangered others, it may be grounds for firing the employee.

For the moment, the practical challenge for employers is proving an employee is impaired by marijuana. To date, there is no quick, easy-to-use and reliable test for current impairment from marijuana.

Urine testing, still widely used, will give positive results long after an employee is no longer impaired. Newer testing technology for saliva is getting close to being a reliable test for current impairment but is not yet recognized as being as reliable as tests for alcohol impairment. At best, such tests can confirm recent use, which may or may not be consistent with impairment. The situation is further complicated by evidence that the degree of impairment resulting from consumption of a given amount of THC, the impairing ingredient of marijuana, may vary across individuals.

For the moment, employers should administer saliva testing or, if testing is delayed, urine testing to corroborate commonly observed symptoms of use and impairment such as marijuana smell on clothes, red eyes, dilated pupils and changes in speech and behaviour. Testing is also permitted following a safety incident where there is reason to believe impairment may have contributed to the incident. But employers need to remember a positive test result without further inquiry and/or other evidence of impairment is not necessarily grounds for dismissal.

For employees who disclose that they are marijuana addicts or whose behaviour is such that the employer should reasonably suspect an addiction, employers must offer reasonable accommodation of the addiction as required under the Human Rights Code.

Like other drug addictions, marijuana addiction is considered a disability, thus imposing a duty on employers to extend “reasonable accommodation” without incurring undue hardship. As with any disability, employers are entitled to receive medical evidence verifying the disability and outlining required treatment and accommodation. Employers may want to insist that an employee seek assessment and treatment from a substance abuse disorder specialist.

Given addiction implies that employees are unable to control their use of marijuana, employers can require employees to provide proof of successful completion of treatment before returning to work and may require both verification of compliance with any doctor prescribed post-rehab therapy and post-return-to-work random testing.

Probably the most challenging scenario is the medical marijuana user.

The employer is entitled to require proof that the employee has a disability and that the employee needs to take marijuana to treat that disability. Minor complaints that do not impose a longer-term substantial impairment of mental or physical functions would not qualify as a disability. The employer should insist on written confirmation from a medical doctor that marijuana is a necessary treatment and does not have to accept notes from the homeopathic and other paramedical practitioners who are providing so many of the “prescriptions” at dispensaries.

Assuming that marijuana is verified as needed to treat a disability, the duty to accommodate will apply. Case law has long established that accommodation of the underlying disability includes reasonable accommodation of the medical treatment of that disability. While the scope of the duty to accommodate will vary according to a variety of factors, including the medical needs of the employee, the employee’s duties and the impact of impairment on safety and productivity, employers are not required to accept impairment while on the job.

Generally speaking, the duty to accommodate will be the same as for an employee taking potentially impairing prescription drugs such as opioids.

In cases where the employee performs safety-sensitive work or works in a safety sensitive environment (e.g. construction site, pulp mill), the employer will be entitled to require that the employee report to work and remain unimpaired during the work day.

Canadian workplace safety legislation requires employees to be free of such impairment at work and obliges employers to enforce this requirement. This might require the employee to abstain from consuming marijuana for a defined period prior to starting work.

Unfortunately experts do not yet agree on how long. Employers might also want to inquire whether the employee can obtain relief by consuming marijuana in a form with reduced or no THC content. The available research suggests that it is the cannabinoids in marijuana that have therapeutic effects, not the THC. So far, no decision requires an employer (or co-workers) to tolerate an employee working in a safety-sensitive role or workplace while impaired by marijuana.

It is more difficult to predict the scope of the duty to accommodate where the employer’s only concern is impaired judgment or productivity, or indeed the impression left with customers by marijuana consumption. It would seem likely that human rights tribunals might require employers to tolerate low levels of impairment if marijuana is legitimately taken to treat a serious medical condition and no other effective, less impairing treatment is available. Employers will need to have evidence that impairment at work has materially affected productivity and/or quality of work before being entitled to take corrective action.

As noted above, if the marijuana is affecting work, employers may be entitled to ask about alternative medications, including low-or-no THC marijuana products or alternative treatments open to the employee.

While marijuana might soon be the first drug after alcohol to be legalized for recreational use in Canada, employers need to remember it should be treated like other impairing substances: like alcohol for recreational users and like any other impairing drug, including prescription drugs, for addicts and medical users.

The anticipated invention of a reliable and easy-to-use test for current marijuana impairment will greatly assist employers to manage the risks of marijuana impairment in the workplace by providing clear proof of such impairment.

In the meantime, employers need to carefully document signs of impairment before taking corrective action. It is also timely to update employer policies to reflect the law on marijuana use outlined above. 

Geoffrey Howard is a partner with Vancouver labour and employment law firm Roper Greyell LLP. This article is intended to convey general information only and should not be considered as legal advice.