TLDR: Ontario employers are legally required under the Occupational Health and Safety Act (OHSA) to investigate every workplace harassment complaint or incident — including informal reports and digital harassment. A defensible investigation must be timely, impartial, thorough, documented, and confidential. This guide walks through the eight-step process, who should investigate, documentation standards, what to communicate to the parties, and the most costly mistakes Ontario employers make.
Table of Contents
- When Is a Workplace Investigation Required in Ontario?
- The Legal Framework: OHSA, Human Rights Code, and More
- Who Should Conduct the Investigation?
- The 8-Step Workplace Investigation Process
- Investigation Timelines
- Documentation Standards
- Confidentiality Obligations
- Communicating Outcomes and Corrective Action
- 10 Common Investigation Mistakes
- Employee Rights During an Investigation
- When to Get Outside HR or Legal Help
- Frequently Asked Questions
When Is a Workplace Investigation Required in Ontario?
Most Ontario employers understand they need to respond to harassment complaints. Fewer understand that the obligation to investigate extends well beyond formal written complaints.
Under section 32.0.7 of the Occupational Health and Safety Act (OHSA), every employer must investigate workplace harassment incidents and complaints. The duty is triggered when an employer:
- Receives a formal written harassment complaint
- Receives an informal verbal complaint
- Observes conduct that may constitute harassment
- Learns of potential harassment through a third party
- Receives an anonymous report
Awareness — not a formal filing — is the trigger. If you know about it, you have an obligation to act.
Beyond harassment, investigations may also be required for:
| Type of Incident | Governing Law | Employer Obligation |
|---|---|---|
| Workplace harassment | OHSA s.32.0.7 | Mandatory investigation |
| Workplace violence | OHSA s.32.0.7 | Mandatory investigation + potential Ministry report |
| Human rights violation (discrimination) | Ontario Human Rights Code | Implied duty to investigate promptly |
| Serious misconduct (theft, fraud) | Common law / ESA | Required before just cause termination |
| Digital harassment (emails, texts, social media) | OHSA (Bill 190, 2024) | Mandatory investigation — same standard as in-person |
A note on digital harassment (Bill 190): As of 2024, Ontario’s OHSA explicitly includes harassment via digital means — text, email, social media, messaging apps. If an employee reports harassing messages sent outside work hours on a personal device, you may still have an obligation to investigate.
The Legal Framework
OHSA Requirements
Ontario’s OHSA requires every employer to have a workplace harassment program that includes:
- A written harassment policy (reviewed annually)
- Measures and procedures for workers to report harassment
- A process for conducting investigations appropriate in the circumstances
- An obligation to inform both the complainant and respondent of investigation results and corrective action
Employers with more than five employees must have a written harassment policy. All employers must conduct investigations, regardless of size.
The Ontario Human Rights Code
When a complaint involves a protected ground under the Ontario Human Rights Code — race, sex, disability, age, sexual orientation, religion, family status, or others — the duty to investigate is reinforced by the Code’s substantive obligations. Failing to take harassment involving protected grounds seriously can result in applications to the Human Rights Tribunal of Ontario (HRTO) and significant damages awards.
Common Law and Just Cause Terminations
If you are investigating potential serious misconduct as a precursor to termination for just cause, the quality of your investigation becomes critical evidence. Ontario courts expect employers to conduct thorough investigations before making just cause determinations. Terminating without investigation — or with a sloppy one — dramatically increases wrongful dismissal exposure.
Who Should Conduct the Investigation?
The choice of investigator is one of the most consequential decisions you will make. OHSA does not require a specific credential, but the investigation must appear objective and impartial. Perceived bias can be as damaging as actual bias.
| Investigator Type | Best For | Limitations |
|---|---|---|
| Internal HR professional | Lower-complexity complaints; peer-level respondents; smaller organizations | Perceived bias risk; reporting relationships may compromise independence |
| Senior manager from another department | Situations where HR is implicated or directly involved | May lack investigation experience; bias concerns if cross-reporting exists |
| External HR consultant | Mid-complexity cases; situations requiring independence; organizations without trained HR | Requires briefing on company culture and policies; higher cost than internal |
| Employment lawyer | Complex cases; high-stakes outcomes; situations likely to result in litigation | Highest cost; legal privilege issues may limit how findings can be shared |
| Licensed private investigator | Serious misconduct investigations; covert surveillance (with legal advice first) | May lack HR or employment law expertise |
Rule of thumb: If the respondent is a senior leader, the case involves multiple complainants or complex facts, there is a prior relationship between the investigator and the parties, or litigation is anticipated — use an external investigator.
The 8-Step Workplace Investigation Process
Step 1: Receive and Document the Complaint
The moment you become aware of a potential incident, document it. Record the date, time, nature of the report, who reported it, and how (in person, email, anonymous tip). Assess immediately whether interim protective measures are needed — for example, whether the complainant and respondent should be separated while the investigation proceeds. Interim separation does not imply guilt; frame it neutrally.
Step 2: Determine Scope and Select an Investigator
Define what is being investigated — specific incidents, a pattern of conduct, or a particular time period. Select the appropriate investigator (internal or external) based on the factors discussed above. Brief the investigator on the workplace context and the relevant policies.
Step 3: Notify the Parties
Both the complainant and the respondent should be informed that an investigation is underway. The complainant should know what to expect from the process. The respondent should be informed that a complaint has been received and that they will have an opportunity to respond — without receiving the full details of the complaint at this stage.
Step 4: Interview the Complainant
Conduct a detailed interview in a private setting. Use open-ended questions. Let the complainant describe events in their own words. Ask follow-up questions to clarify specific details — dates, witnesses, prior communications, whether they reported to anyone previously. Document the interview promptly.
Step 5: Interview the Respondent
Present the substance of the allegations (not necessarily the exact wording of the complaint) and give the respondent a genuine, full opportunity to respond. This is a non-negotiable procedural fairness obligation. Failing to give the respondent a real chance to respond before making findings is one of the most common — and most costly — investigation errors.
Step 6: Interview Witnesses and Gather Evidence
Identify all relevant witnesses — not just those named by the complainant. Obtain and review documentary evidence: emails, text messages, calendar records, access logs, CCTV footage where available and legally appropriate. Preserve evidence as soon as possible to prevent deletion.
Step 7: Analyze Findings and Prepare a Written Report
Assess the credibility of all parties. Consider internal consistency of each account, whether accounts are corroborated by evidence or witnesses, motive to fabricate, and overall plausibility. Apply the balance of probabilities standard — more likely than not that the conduct occurred. Prepare a written report documenting the process, interviews, evidence reviewed, credibility findings, and conclusions.
Step 8: Communicate Outcomes and Implement Corrective Action
As required by OHSA s.32.0.7(4), notify both the complainant and respondent in writing of the investigation results and any corrective action taken. You are not required to share the full report — only the results and corrective action. Implement corrective action promptly and follow up to confirm it is effective.
Investigation Timelines
OHSA does not specify a statutory deadline. But timeliness matters enormously — both legally and practically. An employee who continues to experience harassment while an investigation drags on will have a much stronger claim against the employer.
| Stage | Target Timeline |
|---|---|
| Acknowledge complaint; assess interim measures | Within 24–48 hours |
| Select investigator; define scope | Within 1 week |
| Begin interviews | Within 2 weeks |
| Complete interviews and evidence review | 4–6 weeks |
| Prepare report and communicate findings | Within 90 days of complaint (industry standard) |
Complex cases may take longer. If an investigation will exceed 90 days, communicate with the parties about the delay and the reason for it. Silence during a long investigation feels like inaction to the complainant.
Documentation Standards
The most important protection you have in any employment dispute is documentation. In workplace investigations, this principle applies with particular force. Ontario employment lawyers often say: if it wasn’t written down, it didn’t happen.
Investigation documentation should include:
- The original complaint or incident report
- Notes from each interview (date, time, location, attendees, substance of discussion)
- All documentary evidence reviewed
- List of witnesses considered and reasons for inclusion or exclusion
- Credibility assessments and reasoning
- Final report with findings and recommendations
- Written communications notifying parties of outcomes
Interview notes should be taken contemporaneously — not reconstructed days later. They should capture the substance of what was said, not just your conclusions from it.
Keep investigation files separate from the regular HR files of the parties. Store them securely, with access limited to those with a need to know. Retain for a minimum of six years — consistent with the general limitation period for civil claims in Ontario.
Confidentiality Obligations
Confidentiality is not optional in a workplace investigation — it is a legal and ethical obligation. OHSA requires employers to keep complaint details confidential, disclosing information only as necessary to investigate, take corrective action, or comply with law.
In practice, this means:
- Telling only those who genuinely need to know (investigator, senior HR or management, legal counsel where appropriate)
- Not discussing the matter with uninvolved colleagues, even informally
- Instructing all investigation participants to maintain confidentiality
- Not telling the respondent which other witnesses were interviewed, or what they said
A confidentiality breach — including a manager casually mentioning a complaint to the team — can itself constitute harassment or reprisal, and add a second layer of liability to an already difficult situation.
Communicating Outcomes and Corrective Action
Once the investigation concludes, OHSA requires written notification to both parties. The notification must cover the results and any corrective action. You do not need to share the full report or specify what discipline the respondent received — but both parties must be told that the matter was investigated and what, if anything, is being done.
Corrective action should match the severity of the findings:
- Written warning / formal reprimand
- Mandatory respectful workplace training
- Reassignment or schedule change
- Progressive discipline (where part of an ongoing pattern)
- Termination for cause (where findings are serious and well-documented)
- Policy updates or broader team training
If the complaint was not substantiated, the complainant should still be told that it was taken seriously, fully investigated, and that the employer will continue to monitor the situation.
10 Common Workplace Investigation Mistakes in Ontario
| # | Mistake | Consequence |
|---|---|---|
| 1 | Delaying the investigation | Ongoing harm to complainant; potential Ministry of Labour complaint; HRTO damages |
| 2 | Selecting a biased or untrained investigator | Findings challenged; investigation not defensible in litigation |
| 3 | Reaching conclusions before interviewing all parties | Procedural unfairness finding; increased legal exposure |
| 4 | Failing to give the respondent a genuine opportunity to respond | Natural justice violation; findings potentially invalid |
| 5 | Breaching confidentiality | Harassment or reprisal liability; poisoned workplace claim |
| 6 | Sharing the full investigation report with the parties | Confidentiality risks; litigation exposure if report contains candid credibility findings |
| 7 | Failing to document thoroughly or promptly | Inability to defend findings in court or HRTO proceedings |
| 8 | Not implementing corrective action after substantiated findings | OHSA violation; continued liability for ongoing harassment |
| 9 | Disciplining or terminating the complainant after the complaint (reprisal) | OHSA s.50 violation; significant penalties and damages |
| 10 | Failing to follow up after the investigation concludes | Recurrence; potential claim that corrective action was inadequate |
Employee Rights During a Workplace Investigation
Both parties have rights in a workplace investigation. Understanding them helps you run a process that will hold up to scrutiny.
Complainant rights:
- Right to have the complaint treated seriously and investigated promptly
- Right to be informed of investigation results and corrective action (OHSA s.32.0.7(4))
- Right to protection from reprisal for making a complaint (OHSA s.50)
- Right to request an external investigator if there are genuine impartiality concerns
Respondent rights:
- Right to be informed that a complaint has been received and the general nature of the allegations
- Right to respond to the allegations before any findings are made
- Right to union representation in unionized workplaces
- Right to be informed of the investigation results
- Right not to be disciplined before the investigation is complete (in most circumstances)
Witnesses who provide information during an investigation are also protected from reprisal under OHSA s.50.
When to Get Outside HR or Legal Help
Most Ontario employers are not equipped to handle complex investigations internally. You should bring in external support when:
- The respondent is a senior leader, founding partner, or executive
- The complaint involves potential human rights violations
- The organization lacks trained, impartial HR staff
- The case is complex — multiple complainants, disputed facts, extensive evidence
- Prior investigations have been challenged or produced unsatisfactory outcomes
- The situation is likely to result in termination for just cause
- The complainant has engaged legal counsel or threatened to file an HRTO application
A well-run external investigation is typically less expensive than the cost of defending a poorly run internal one. If you are facing a harassment complaint and are uncertain about your obligations, speak with an HR consulting professional before proceeding.
Learn more about HRX Connect’s HR consulting services, our approach to workplace harassment investigations, and our progressive discipline guide for Ontario employers.
Frequently Asked Questions
Are Ontario employers legally required to investigate workplace harassment complaints?
Yes. Section 32.0.7 of the OHSA requires every Ontario employer to investigate workplace harassment complaints and incidents appropriately in the circumstances. Awareness of a potential incident — not a formal written complaint — is sufficient to trigger the obligation.
How long does an investigation have to take?
OHSA sets no statutory deadline. The HRPA‘s practice standard and Ontario caselaw point to 90 days as the expected standard for most cases. Significant delays can constitute inadequate employer response.
Do I have to share the investigation report?
No. You must notify both parties of results and corrective action (OHSA s.32.0.7(4)). You are not required to share the full report and generally should not, as doing so creates confidentiality and litigation risks.
Can I investigate internally?
Yes, for straightforward cases involving non-senior employees where a trained, genuinely impartial investigator is available. External investigators are recommended for complaints involving senior leadership, complex facts, or anticipated litigation.
What standard of proof applies?
The civil standard: balance of probabilities. More likely than not that the conduct occurred. Lower than the criminal standard of beyond a reasonable doubt.
Can I terminate an employee while the investigation is ongoing?
Generally no — significant discipline or termination should wait for investigation completion. In cases of immediate safety risk, the respondent can be placed on paid administrative leave while the investigation proceeds.
The Bottom Line
Workplace investigations are among the highest-risk HR functions for Ontario employers. Done well, a thorough and impartial investigation resolves complaints, protects your organization, and reinforces a respectful workplace culture. Done poorly — or ignored entirely — it compounds your legal exposure and can result in OHSA violations, HRTO proceedings, wrongful dismissal claims, and significant damages.
If you are dealing with a workplace harassment complaint or want to build a defensible investigation process before you ever need it, HRX Connect’s HR consulting team can help. We work with Ontario employers on investigation process design, act as external investigators when internal capacity is limited, and provide the documentation and policy frameworks that protect you when things go wrong. Contact us to discuss your situation.