Here's a scenario most HR leaders think protects them: an employee tells a supervisor about offensive messages from coworkers but says, "I don't want to make a big deal about it." No formal complaint is filed. No written statement. No investigation form submitted.
You're off the hook, right?
Wrong. The Ontario Divisional Court made that unequivocally clear — and the Court of Appeal agreed.
What Happened at Metrolinx
Five Metrolinx employees created a private WhatsApp group chat on their personal phones, outside of working hours. In that chat, they made derogatory and sexist comments about colleagues — including allegations that a female employee (referred to as "Ms. A") had performed sexual favours to advance her career.
Ms. A received screenshots of the messages. She told a supervisor. But she explicitly declined to file a formal complaint and said she didn't want the matter pursued.
Months later, HR became aware of the screenshots independently. They launched an investigation anyway. All five employees were terminated for cause.
The union grieved the terminations, and an arbitrator reinstated the employees — reasoning, in part, that Ms. A hadn't wanted an investigation and the conduct occurred off-duty on personal devices.
Metrolinx challenged that decision. The Divisional Court overturned it.
The Court's Ruling: Incidents, Not Just Complaints
The critical legal point is in the language of OHSA Section 32.0.7(1)(a). It doesn't say employers must investigate complaints. It says employers must investigate incidents and complaints of workplace harassment.
The Divisional Court held that:
A formal complaint is not a precondition to the duty to investigate. Once an employer becomes aware of a potential incident of workplace harassment — through any channel — the investigation obligation is triggered.
The duty isn't owed only to the complainant. It's owed to all employees in the workplace. Every worker has a right to an environment free from demeaning and offensive conduct. One person's wish to let it go doesn't extinguish the employer's obligation to the broader workforce.
Off-duty conduct can constitute workplace harassment. The fact that the WhatsApp messages were sent on personal devices, outside of working hours, didn't matter. The messages targeted colleagues and were capable of affecting the work environment.
The Court of Appeal dismissed the union's appeal in 2025 ONCA 415, confirming the Divisional Court's order.
Why This Changes the Calculus for Employers
Before Metrolinx, many employers operated under a practical — if legally questionable — assumption: no complaint, no investigation. This ruling eliminates that position entirely.
Here's what it means in practice:
Supervisors who "hear things" trigger the obligation. If a manager overhears comments, receives forwarded messages, or learns about conduct through any informal channel, the employer is now on notice. The clock starts.
"The employee doesn't want to pursue it" is not a defence. Respecting an individual's preference not to file a complaint is understandable from a human perspective — but it doesn't satisfy the employer's statutory duty under the OHSA. You can be compassionate and still investigate.
Off-duty digital conduct is in scope. Private group chats, social media posts, text messages — if they target colleagues and could affect the work environment, they're potentially workplace harassment under the OHSA. The personal-device, after-hours defence is dead.
Arbitrators who get it wrong will be overturned. The Divisional Court sent a clear message: the OHSA's investigation duty is non-negotiable, and arbitral decisions that undermine it won't stand.
What Ontario Employers Should Do Now
1. Update your harassment policy. Your policy should explicitly state that investigations may be initiated based on incidents — not only formal complaints. Remove any language suggesting a written complaint is required to trigger an investigation.
2. Train supervisors and managers. Every people leader needs to understand that learning about potential harassment — through any means — creates a reporting obligation. "I didn't want to get involved" is no longer an option.
3. Establish incident reporting protocols. Create a clear, simple process for managers to report potential harassment incidents to HR, even when no formal complaint has been made. Document everything.
4. Review your investigation scope. Your workplace investigation process should account for off-duty conduct that targets colleagues. Don't assume personal devices or after-hours timing puts conduct outside your jurisdiction.
5. Get the investigation right. When the duty to investigate is this broad, the quality of the investigation matters even more. A flawed investigation doesn't just fail to protect employees — it creates its own liability. If you don't have trained investigators on staff, bring in an external professional.
The Bottom Line
The OHSA places an absolute duty on Ontario employers to investigate every incident of workplace harassment. Not just the ones filed in writing. Not just the ones an employee formally pursues. Every single one.
If your organization is still operating under the assumption that no complaint means no investigation, you're exposed. The Metrolinx ruling isn't new law — it's a court confirming what the statute always required. The question is whether your policies, training, and investigation processes reflect that reality.
Need help assessing whether your workplace investigation framework meets the standard? Talk to our team. We conduct independent, legally defensible workplace investigations for organizations across Ontario — and we can audit your existing policies before a problem becomes a liability.