It's 11pm. You've just received an email from an employee describing harassment. Your immediate question isn't "how do I fix this?" — it's "am I legally required to investigate?"
The answer is yes. And the consequences of skipping it are severe enough that you need to take this seriously.
The Legal Framework (Yes, It's Real)
Ontario doesn't have a single "investigation statute." Instead, your obligation to investigate comes from three overlapping legal sources:
1. Occupational Health and Safety Act (OHSA) — Section 32 Every employer must "take all reasonable precautions to protect the health and safety of a worker." This includes workplace harassment and violence. When you receive a harassment complaint, Section 32 requires you to investigate. Full stop. This applies to every workplace in Ontario.
2. Ontario Human Rights Code — General Duty of Care Under the Human Rights Code, employers have a common law duty of care to employees. This includes investigating discrimination and harassment complaints. Failure to investigate competently has resulted in $200K+ settlements and awards at the Human Rights Tribunal of Ontario (HRTO).
3. Employment Standards Act (ESA) While less direct, the ESA requires investigation when termination decisions are made (e.g., you fire someone for misconduct without investigating). A wrongful dismissal claim based on insufficient investigation routinely exceeds $50K for cause termination.
These aren't optional frameworks. They're statutory minimums.
For a detailed breakdown of OHSA Section 32 requirements and enforcement, see OHSA Section 32: Employer Investigation Obligations.
What "Legally Required" Actually Means
A legal obligation to investigate means:
- You must respond to the complaint in writing — acknowledge receipt and provide a timeline
- You must conduct a reasonably thorough investigation — not a cursory chat with the person involved
- You must interview relevant witnesses — people with direct knowledge
- You must document the investigation — notes, interview summaries, evidence
- You must reach findings based on evidence — "on the balance of probabilities" in Canadian law
- You must communicate outcomes (with appropriate confidentiality constraints)
- You must take remedial action if misconduct is found
If you skip investigation and fire the person instead, you're exposed to:
- Wrongful dismissal claim ($50K-$200K+ in severance alone)
- HRTO discrimination complaint ($50K-$150K in damages)
- WSIB/occupational health claim if stress/mental health injury is involved
- Constructive dismissal claim if the complainant leaves instead
When Investigation Is Absolutely Mandatory
1. Any Harassment or Violence Allegation Under OHSA, workplace harassment (unwelcome conduct, comment, or action based on protected grounds) triggers mandatory investigation. This includes sexual harassment, racial harassment, disability-based harassment, or any pattern of unwelcome conduct.
2. Discrimination Claims If someone alleges they've been treated differently because of race, gender, age, disability, religion, sexual orientation, family status, marital status, gender identity, or gender expression — investigate. The Human Rights Code makes this non-negotiable.
3. Safety Concerns Someone reports unsafe working conditions, equipment failure, or health/safety violations — investigate. OHSA requires it.
4. Serious Misconduct with Liability Allegations of theft, fraud, breach of confidentiality, conflict of interest, or gross insubordination that could result in termination — investigate. Otherwise, your termination decision is legally indefensible.
5. Complaints That Involve Multiple People One-on-one conflict often settles privately. But when multiple people report the same issue ("I've heard he's treated three female employees this way") — that's a pattern, and pattern requires investigation.
What Happens If You Don't Investigate
Scenario 1: You Don't Investigate, But Keep the Person Result: The complaint is on record. The harassment continues (or appears to). The complainant files a human rights board complaint, naming you as the employer. Your failure to investigate becomes evidence of negligence. Tribunal awards: $30K-$100K+ in damages, plus the employee's legal fees.
Scenario 2: You Don't Investigate, You Terminate the Complainant Result: Wrongful dismissal lawsuit + human rights discrimination complaint (allegation of retaliation). You've terminated without cause and without due process. Settlement: $75K-$200K+.
Scenario 3: You Don't Investigate, You Terminate the Respondent Result: Respondent sues for wrongful dismissal (didn't get opportunity to respond). Your termination was based on unverified allegations. You lose. Settlement: $100K-$300K+ depending on tenure and damages.
Scenario 4: You "Investigate" Improperly (Bias, Conflict of Interest, No Due Process) Result: Investigation is challenged as unfair. Tribunal finds the investigation itself was discriminatory or procedurally flawed. Your investigation doesn't protect you — it incriminates you. Award: $50K-$150K+ with potential punitive damages.
The cost of not investigating, or investigating poorly, starts at $50K and climbs from there. The cost of investigating properly: $12K-$35K.
What "Reasonable" Investigation Looks Like Under Ontario Law
Case law from HRTO and courts has established benchmarks for a defensible investigation:
- Timeliness — Start within 5-10 business days of complaint. Delay suggests you didn't take it seriously.
- Independence — Investigator has no conflict of interest with either party.
- Due process — Both complainant and respondent are interviewed. Respondent gets opportunity to respond to allegations.
- Evidence-based — Credibility is assessed systematically. You can't just believe one person over another because you like them better.
- Documentation — Interview summaries, timeline of events, evidence list, reasoning for credibility findings.
- Clear findings — You state what happened, or didn't happen, and why you concluded that.
- Appropriate remediation — If misconduct found, reasonable corrective action is taken.
Missing even one of these elements weakens your defense in a tribunal hearing.
For a complete walkthrough of the investigation process and what to expect at each stage, see The Complete Guide to Workplace Investigations in Ontario.
The Common Mistakes That Destroy Your Legal Position
Mistake 1: Manager Investigates a Complaint Against Their Own Employee The manager has a conflict of interest. Whatever they find will be questioned. Use an external investigator or HR professional instead.
Mistake 2: You Investigate, Find Misconduct, Do Nothing You've documented the problem — now you're liable for ongoing harm. Finding misconduct requires action (counseling, suspension, termination, retraining). Inaction is negligence.
Mistake 3: You "Investigate" via Email Written email can't assess credibility, tone, body language, or clarify contradictions. Interviews must be in-person or video (at minimum). Email-only investigation looks negligent in tribunal proceedings.
Mistake 4: You Don't Preserve Evidence Before investigation starts, you must preserve all relevant communications — emails, Slack messages, calendar invites, video calls. If evidence disappears after the complaint, it looks like destruction of evidence.
Mistake 5: You Tell the Complainant "Don't Talk to Anyone" Reasonable confidentiality ≠ gag order. Complainants have the right to discuss their complaint with a union rep, lawyer, or trusted colleague. Over-restricting their speech looks retaliatory.
Your Actual Legal Obligation in Plain Language
When you receive a complaint of harassment, discrimination, or serious misconduct:
- Acknowledge it in writing within 3 business days
- Hire an independent investigator (HR professional or lawyer, depending on complexity and legal risk)
- Conduct interviews with both parties and relevant witnesses
- Document findings based on evidence
- Communicate outcomes to the complainant and respondent (maintaining appropriate confidentiality)
- Take remedial action proportional to the findings
- Follow up to ensure no retaliation and that remediation worked
This is not optional. This is what Ontario law requires.
When You're Unsure About Your Obligation
Ask yourself these questions:
- Is there an allegation of unwelcome conduct? (OHSA applies)
- Does the allegation involve a protected ground (gender, race, age, disability, etc.)? (Human Rights Code applies)
- Could this person be fired for what's alleged? (Due process required)
- Would a reasonable employer investigate this? (Common law applies)
If you answer "yes" to any of these, you need an investigation.
For guidance on executing each step and understanding the investigation timeline and process, see Workplace Investigation Process: Step-by-Step Guide.
The Bottom Line
You are legally required to investigate complaints of harassment, discrimination, and serious misconduct in Ontario. This isn't negotiable. The law comes from OHSA, the Human Rights Code, and common law principles established through decades of tribunal and court decisions.
The cost of investigating properly: $12K-$35K. The cost of not investigating: $50K-$300K+ in settlements, awards, and legal fees, plus reputational damage and operational disruption.
Not sure whether your specific situation requires an investigation? Talk to us. We'll walk you through your legal obligations, outline what investigation would look like, and help you make the right decision. It's too important to guess.