CCPartners | Blog

Khushi Dave


Related Blogs by Category
Human Resources Support




Arbitrator Rules Employer’s Two-Dose COVID Vaccine Requirement Not Reasonable (Anymore…)

Practice Areas: Human Resources Support

In what appears to be a significant departure from recent arbitral decisions, an employer’s COVID-19 vaccination policy has been deemed unreasonable in light of new scientific data.  In FCA Canada Inc. v Unifor, Locals 195, 444, 1285, the Employer implemented its policy on October 14, 2021.  The policy required, in part, that employees, contractors, suppliers, and visitors were required to be fully vaccinated with two doses of a two-dose vaccine in order to attend the workplace. If an employee did not abide by this requirement of the policy, they would be placed on unpaid leave of absence, and possibly terminated for non-compliance.  The Union grieved that the policy was once reasonable, but now was not.  The parties presented their arguments on May 25, 2022 and Arbitrator Marilyn Nairn eventually ruled that the two-dose vaccine requirement was unreasonable.

At hearing, the Union argued that recent scientific studies had shown that two-dose vaccines were no longer effective against transmitting COVID (specifically with regard to the vaccines’ effectiveness against the Omicron variant). Hence, the Union argued that the vaccination policy be deemed unreasonable, and employees who are on unpaid leave be fully compensated.

The Employer argued that the evolution in the scientific evidence was not as clear and consistent as the Union suggested, and that vaccines remained  effective in preventing serious illnesses. Moreover, Public Health guidelines still encouraged vaccinations as a means to prevent unvaccinated individuals from becoming infected and transmitting COVID to those who are vaccinated.

The Arbitrator noted from the outset of her decision that “The fundamental factor in dispute in this case is the reasonableness of the Policy in the circumstances of the Employer’s workplaces in the context of changing nature of the COVID-19 pandemic.”  In order to assess that context, the Arbitrator considered, among other things, the following findings from various global scientific studies:

  • A pre-print study from the U.K. Health Security Agency reviewed vaccine effectiveness against the Omicron variant. It concluded that primary series immunization (2 doses) with either Pfizer or AstraZeneca provided limited or no protection against infection and mild disease. Boosting with the Pfizer vaccine was found to offer an increase in protection, but at the time that this study was conducted, the duration of that increased protection was not known.
  • Another study by the U.K. Health Security Agency, published April 28, 2022, concluded that, while vaccine effectiveness against Omicron from two doses of an mRNA vaccine dropped from 65-70% to about 15% by week 25, booster doses of an mRNA vaccine provided some renewed protection against symptomatic Omicron infections. Protection against hospitalization and death related to COVID-19 remained strong after a second dose but was more robust after a booster dose.
  • A Danish pre-print study published in December 2021 found that the comparative levels of transmission between an infected unvaccinated and infected two-dose vaccinated person was statistically insignificant.


The Arbitrator took care to review previous decisions upholding the reasonableness of workplace COVID-19 vaccine policies, of which there are many that you can review in CCPartners’ Complete Rundown of COVID-19 Vaccine Policy Decision.  In particular, she rejected the idea that employees had a blanket entitlement to remain unvaccinated without consequence, stating:

I observe that there is no “right” to remain unvaccinated and remain in active employment. The right is one of personal autonomy and bodily integrity, in this circumstance, having the choice to remain unvaccinated. Exercising that choice may give rise to other impacts. For every right there is a corresponding responsibility – the Employer has the right to make workplace rules but has the corresponding responsibility to ensure that those rules are reasonable. An employee has the right to remain unvaccinated but has a corresponding responsibility not to place co-workers at increased risk as a result. Notably, the tension between these two interests can be acute, because a COVID-19 vaccine mandate was not an original condition of employment but has been newly introduced into the workplace, affecting existing employees who are now faced with what, for some, is a significantly difficult choice between remaining unvaccinated or continuing in active employment.

Indeed, it was a factual finding based on the available studies that the Arbitrator found compelling.  She decided that “Emerging evidence does indicate that a two-dose vaccine regimen provides significantly less protection against infection from Omicron and its sub-variants than with prior variants.”

Accordingly, and in the particular and discrete circumstances of this case, the Arbitrator declared that the Employer’s policy was indeed unreasonable:

…I hereby find that a COVID-19 vaccine mandate defined as requiring two doses (of a two-dose vaccine) is no longer reasonable based on the evidence supporting the waning efficacy of that vaccination status and the failure to establish that there is any notable difference in the degree of risk of transmission of the virus as between the vaccinated (as defined in the Policy) and the unvaccinated. Rather, the evidence supports a conclusion that there is negligible difference in the risk of transmission in respect of Omicron as between a two-dose vaccine regimen and remaining unvaccinated. There is, under the definition in the Policy, no longer a basis for removing unvaccinated employees from the workplace…

Arbitrator Nairn declared the policy to be of no force or effect as of June 25, 2022.  However, she left the door open for the Employer to revise the policy rather than vacate it altogether.

Takeaways for Employers

This case illustrates that while there may be still be uncertainty about how vaccination policies will be interpreted in the future, recent and developing scientific evidence are a crucial factor in determining whether a policy will be considered reasonable by labour arbitrators.  Arbitrator Nairn could not have been more clear that her decision was based on the particular circumstances of these workplaces over the relevant period, in relation to the Policy as written and the available science.  She noted that any or all of those circumstances may change, which accordingly could change the outcome of a similar grievance.

Employers who are reconsidering their COVID-19 vaccination policies should take steps to understand the factual context in which they operator, including public health guidance and scientific consensus.

If you have further questions or require more information in regard to COVID-19 policies, don’t hesitate to contact the team at CCPartners.

Click HERE to access CCPartners' “Lawyers for Employers” podcasts on important workplace issues and developments in labour and employment law.



Crawford Chondon & Partners LLP is committed to providing an inclusive workplace that embraces and respects differences.  We support and promote the ongoing development, implementation and maintenance of best practices and strategies to enhance and improve equality, diversity and inclusion within the Firm, in advising clients and in the greater community. Click to learn more about our Diversity and Inclusion 

Main Office Map
24 Queen Street E.

Suite 500
Brampton, ON  L6V 1A3

P: 905.874.9343  TF: 1.877.874.9343
F: 905.874.1384  E:
Barrie Office  Map

132 Commerce Park Drive
Suite 253, Unit K
Barrie, ON L4N 0Z7

P: 705.719.2107 F: 1.866.525.8128


Sudbury Office  Map

10 Elm Street
Suite 603
Sudbury Ontario P3C 5N3

P: 705.805.0174


Privacy | Accessibility | Disclaimer