Mar 3, 2026  By John Hyde

Attention Ontario Employers: Firing Employee for Defamatory Social Media Post is Not Reprisal or Unfair Labour Practice Based on Timing Alone, Court Rules

A series of recent Ontario decisions demonstrate that an employee being dismissed shortly after they engage in union organizing efforts and/or making occupational health and safety complaints does not necessarily amount to an unfair labour practice or unlawful reprisal based on the timing alone. In Cai Song v. Ontario Labour Relations Board, the Ontario Divisional Court upheld a previous decision by the Ontario Labour Relations Board (“OLRB”) which found that an employee was fired solely because he had refused to take down a “defamatory” social medial post about his employer, and that the dismissal was not an unlawful reprisal or unfair labour practice. This was despite that: (i) the social medial post suggested that the employee was engaged in union organizing; (ii) the employee had made harassment allegations in the months leading up to his dismissal; and (iii) the employee made a complaint to the Ministry of Labour just prior to his dismissal.

Background

Mr. Cai was a lawyer in China before he immigrated to Canada and commenced part-time employment with T&T Supermarkets Inc. (“T&T”) in the produce department. When T&T initiated disciplinary investigations in relation to Mr. Cai taking excessive breaks and having an angry outburst toward a colleague, Mr. Cai responded by making harassment complaints against the colleague and his manager. The timing of these complaints was suspicious, but T&T investigated and found them to be unsubstantiated, which it communicated to Mr. Cai on November 20, 2023.

On November 25, 2023, Mr. Cai made a long social media post on the York BBS (“YBBS”), a social media platform which caters to the Chinese Canadian community—T&T’s target market. The beginning of this post asserted that T&T: (i) discriminated against White people by not hiring them; (ii) oppressed Chinese people and profited off of their “blood and tears”; and (iii) had “the majesty of the party-state”. The post also contained numerous confidential internal communications and documents related to Mr. Cai’s previous harassment complaints, as well as comments which suggested that Mr. Cai was engaged in union organizing at T&T and had made a complaint to the OLRB.

T&T became aware of this post on November 28, 2023, and it repeatedly directed Mr. Cai to take down this post on the basis that it was “defamatory” and breached company policies by disclosing confidential information. Mr. Cai refused and T&T decided to terminate his employment on the morning of November 28, 2023. However, Mr. Cai repeatedly refused to attend the termination meeting, such that his employment was ultimately terminated via a letter on November 30, 2023.

During this same period, Mr. Cai had signed a union card and began acting as an inside union organizer on November 2, 2023. He also made a complaint against T&T under the Occupational Health and Safety Act (“OHSA”) on November 22, 2023. The Ministry of Labour (“MOL”) conducted an inspection of the T&T store that Mr. Cai worked at in the afternoon of November 28, 2023 in response—after T&T decided to dismiss him but before it actually did so. The MOL found that Mr. Cai’s allegation that T&T had failed to post a workplace violence and harassment policy was unsubstantiated, as one was posted in the workplace.

Following his dismissal, Mr. Cai filed applications with the OLRB alleging that his dismissal was a reprisal under the OHSA and an unfair labour practice under the Labour Relations Act (“LRA”), arguing that his MOL complaint and union organizing efforts were both factors in T&T’s decision to dismiss him.

The Decisions

The OLRB dismissed Mr. Cai’s reprisal and unfair labour practice applications because it found that the sole reason for his dismissal was his refusal to remove his “defamatory” social media post about T&T, and not because he had engaged in union organizing activities or made any OHSA-related complaints.

In dismissing Mr. Cai’s applications, the OLRB held that it would constitute an unfair labour practice contrary to section 72 of the LRA if any part of T&T’s decision to dismiss Mr. Cai was related to his union organizing efforts. Likewise, the OLRB held that if any part of this decision was related to Mr. Cai making complaints under the OHSA, this would constitute an unlawful reprisal contrary to section 50 of the OHSA. The OLRB further held that: (i) the employer bears the evidentiary burden of proving that the dismissal was not related to the protected activity in question; and (ii) where there are “peculiarities” surrounding an employer’s decision to dismiss an employee (e.g., where this occurs shortly after they have engaged in union organizing or asserted their rights under the OHSA), the employer must provide a reasonable explanation for those peculiarities in order to discharge its evidentiary burden.

In this case, the OLRB found that T&T’s various witnesses were credible in testifying that the decision-makers who decided to terminate Mr. Cai’s employment were not aware of his union organizing activities nor his MOL complaint when they made that decision. Thus, although the social media post made references to T&T’s handling of Mr. Cai’s harassment complaints under the OHSA and suggested that he was engaged in union organizing activity, the accepted evidence demonstrated that: (i) the decision-makers were focused on the “defamatory” nature of the post and Mr. Cai’s breach of confidentiality requirements; and (ii) they were not aware of any union organizing or MOL complaint until the decision to dismiss him had already been made. Consequently, the OLRB dismissed Mr. Cai’s applications.

Mr. Cai challenged the OLRB’s decision to dismiss his applications by applying for judicial review with the Ontario Divisional Court. This application was also unsuccessful, with the court upholding’s the OLRB’s decision as reasonable and ordering Mr. Cai to pay T&T $7,500 in costs.

The Bottom Line

Although the suspicious timing of a dismissal can establish unlawful reprisal or an unfair labour practice, the Cai decision illustrates that timing is not determinative, and that what decision-makers knew at the time that they decided to dismiss the employee is crucial.

As a result, employers would be well advised to keep written records of when and why they have decided to terminate an employee’s employment, particularly where the employee has also engaged in any protected activities under the OHSA, LRA, Employment Standards Act, 2000, or Human Rights Code in the months leading up to their dismissal. Furthermore, this is a best practice even where the employer is not aware of the employee engaging in any such protected activities, because the employee may be engaging in them without the employer’s awareness or begin engaging in protected activities while the employer is still in the process of implementing the dismissal. By being proactive, employers can arm themselves with strong evidence to defend themselves and minimize risks of potential unfair labour practice and unlawful reprisal complaints.

If you require any assistance with navigating a risky termination of employment or defending against an unfair labour practice or reprisal complaint, please do not hesitate to contact us for expert legal advice and guidance. 

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