In the case M. v. Amalgamated Transit Union, Local 1587 (2025 ONCA 415), the Ontario Court of Appeal confirmed that employers have a legal duty to investigate workplace harassment once they become aware of it, even if the affected employee does not file a formal complaint.
This decision matters for employees because it reinforces your right to a respectful, harassment-free workplace.
What Happened
Several employees participated in a private group chat where they made sexist and derogatory comments about a coworker, including allegations of sexual favours for career advancement.
The employee later received screenshots of the messages and reported them to a supervisor, but chose not to file a formal complaint or take part in an investigation.
Months later, when human resources learned about the messages, the employer launched an investigation. After reviewing the findings, the employer terminated the employees involved for sexual harassment.
The union challenged the dismissals. An arbitrator initially ordered reinstatement, reasoning that because the employee did not want to pursue a complaint, the employer had no authority to investigate private, off-duty communications.
Both the Divisional Court and the Court of Appeal disagreed and upheld the terminations.
Key Legal Findings
Off-duty conduct can lead to workplace discipline
Employers can discipline off-duty conduct when it has a real impact on the workplace. Even conduct on personal devices outside work hours can lead to discipline if it harms the workplace environment or the employer’s legitimate interests.
Here, the messages reached the workplace, upset the employee, and had an impact at work. That was sufficient.
A formal complaint is not required
Under Ontario’s Occupational Health and Safety Act, employers must investigate both “incidents and complaints” of workplace harassment. Once an employer becomes aware of an incident, the duty to investigate is triggered — even if no formal complaint is filed.
This obligation exists to protect all employees, not only those who actively complain.
“Private” messages are not immune from consequences
The Court of Appeal rejected the idea that encrypted or personal messaging is outside an employer’s authority when the content affects the workplace.
Once the comments were shared, seen by the employee, and had workplace effects, they became a workplace issue.
An employee’s reluctance does not cancel the duty to investigate
The court emphasized that a victim’s hesitation to pursue a complaint does not mean harassment did not occur or had no workplace impact.
Employees may avoid formal complaints for many reasons, including fear of retaliation, workplace dynamics, or emotional exhaustion. Decision-makers cannot rely on stereotypes about how victims “should” respond.
The agreed facts showed the employee was distressed at work, which established workplace impact.
Procedural Arguments Rejected
The terminated employees argued the employer acted unfairly by missing internal timelines, investigating without a formal complainant, requesting access to messages on a personal phone, and applying inconsistent standards.
The Court of Appeal rejected these arguments, finding the employer’s statutory duty to investigate overrides internal policies. Once concerning messages surfaced, the investigator was entitled to seek full context.
Key Takeaways for Employees
- Your employer must act. If harassment comes to management’s attention, the employer is legally required to investigate — even if you do not want to proceed formally.
- Off-duty does not always mean off-limits. Messages about coworkers, even in private chats, can lead to discipline if they affect the workplace.
- You do not have to complain for your experience to matter. The law recognizes that many people do not file formal complaints. That does not invalidate what happened.
- Not all off-duty conduct leads to discipline. The bar remains high, but derogatory comments about coworkers that surface at work and cause harm can cross the line.
Why This Decision Matters
The Ontario Court of Appeal sent a clear message: workplace harassment requires employer action, whether or not a formal complaint is filed.
If you have been terminated following a workplace investigation, or if you have experienced harassment at work, the specific facts matter. Outcomes often depend on what was said, how it reached the workplace, and the impact it had.
Questions about workplace harassment or wrongful dismissal? Contact Monkhouse Law Employment Lawyers for a free 30 min phone call to discuss your situation. Monkhouse Law represents non-unionized employees.