Workplace Investigations in Ontario: A Practical Guide
When concerns about harassment, discrimination, violence, bullying, safety, fraud, conflicts of interest, or policy breaches arise, a workplace investigation is often legally required—and always a key risk-control step. This guide explains when you must investigate, how to do it fairly, what to tell the parties, and how federal rules differ from Ontario’s.
The big picture (what the law expects)
Act promptly. Start quickly and aim to finish within a reasonable timeline.
Be appropriate to the circumstances. Not every case needs a full-blown, external investigation—but every case needs a fair, proportionate process.
Be impartial and thorough. No conflicts, no pre-judgment, and enough fact-finding to reach a defensible conclusion on a balance of probabilities (more likely than not).
Communicate outcomes in writing. Provide both the complainant and respondent with a written outcome and any corrective action.
Protect against retaliation. No reprisals for reporting, participating, or giving evidence.
When you must investigate (Ontario focus)
Under Ontario’s health and safety law, employers must ensure an investigation “appropriate in the circumstances” into incidents or complaints of workplace harassment. That obligation doesn’t depend on magic words or a formal complaint—if you know or ought to know about potential harassment, you must act.
You must also have a written harassment policy and program, training, and a way to report to someone other than the supervisor/employer if they’re implicated.
For workplace violence, your program must set out how incidents will be investigated and dealt with, alongside risk assessment, controls, and emergency measures.
Separate from health and safety, the Human Rights Code expects organizations to address and, where warranted, investigate alleged discrimination and harassment on protected grounds (e.g., sex, race, disability). A poor response can itself breach the Code.
Who should investigate?
Choose an investigator who is:
Independent and impartial (no stake in the outcome, no prior involvement).
Competent (trained in investigations, interviewing, credibility assessment, and writing defensible reports).
Appropriate to the case (e.g., trauma-informed skillset for sexual harassment; language/cultural competency where needed).
Use an external investigator where the alleged harasser is senior leadership, where neutrality might be questioned, or where internal capacity is limited. Inspectors can, in some circumstances, order an investigation by an impartial third party at the employer’s expense.
Privilege? If you retain external legal counsel to direct the investigation for the purpose of giving legal advice, some communications may be protected by solicitor–client privilege. That said, you still have to communicate the results and any corrective action to the parties in writing.
The investigation roadmap (step by step)
Triage & interim safety
Stabilize the workplace: safety planning, schedule changes, separating parties, administrative leave if warranted.
Remind everyone about anti-reprisal and confidentiality expectations (limited to what’s necessary to investigate and act).
Plan the mandate
Define the issues, timeframe, and policies engaged.
Identify what documents, messages, audio/video, or system logs you need. Preserve evidence (litigation hold if appropriate).
Notices to the parties
Tell the complainant what will happen, timelines, and what confidentiality means (and doesn’t mean).
Give the respondent clear particulars of the allegations and a real chance to respond.
Interviews & evidence
Use fair, open-ended questioning.
Test credibility using consistency, plausibility, corroboration, and contemporaneous records—not demeanor alone.
Follow up on new leads; keep notes contemporaneously and securely.
Analyze and decide (standard of proof)
Apply the balance of probabilities: is it more likely than not that the alleged conduct occurred?
Make clear findings: substantiated, not substantiated, or inconclusive (with reasons).
Outcome & corrective action
Calibrate responses to the findings (coaching, training, apologies, warnings, discipline up to termination, structural changes, team resets).
Address systemic issues (policy gaps, supervision, workloads, culture).
Follow up with the complainant on safety and restoration, and with the respondent on expectations.
Closure letters (mandatory in Ontario harassment cases)
Provide both parties in writing with the results and any corrective action you have taken or will take.
Use plain language. Be specific enough to be meaningful; do not promise or imply absolute confidentiality.
Records & retention
Keep investigation files secure and separate from general personnel files.
Retain key materials (complaint, notices, notes, evidence list, report/summary, closure letters, and proof of training).
Your other legal frameworks (for example, federal rules if you’re a federally regulated employer) may set longer retention periods.
What the parties should (and shouldn’t) expect
Complainant: a timely, fair process; a chance to be heard; updates; a written outcome and corrective action; protection from reprisals.
Respondent: timely particulars; a chance to respond; a fair, unbiased process; a written outcome and corrective action; protection from reprisals.
Witnesses: dignity, limited-disclosure confidentiality, and no reprisals.
Representation? In unionized settings, collective agreements usually address the right to have a representative at investigatory meetings. In non-union settings, offering a support person is best practice but not a general legal right in Ontario.
Special topics & common pitfalls
No formal complaint, just rumours? If you’re aware of potential harassment or violence, you still need to assess and, if warranted, investigate.
Don’t over-promise confidentiality. Share information only as needed to investigate, act, or comply with law—but don’t promise secrecy you can’t deliver.
Bias & conflicts. Recuse conflicted leaders; don’t assign a manager who will later decide discipline to also make factual findings unless unavoidable and disclosed.
Speed vs. fairness. Move promptly, but don’t cut corners on notice, particulars, or the respondent’s chance to be heard.
Poor outcome letters. In Ontario harassment files, your closure letters must do more than say “we handled it.” They should identify who was found to have harassed (if applicable) and what corrective measures you are taking—without divulging unnecessary detail.
Retaliation. Any negative actions tied to someone raising or participating in a complaint risk reprisal findings, separate from the merits of the case.
How federal rules differ (quick note for federally regulated employers)
If you’re federally regulated (banks, airlines, telecom, interprovincial transport, Crown corporations), you follow the Work Place Harassment and Violence Prevention Regulations under the Canada Labour Code. Expect more formal joint development with your committee/representative, defined timelines (for example, contact within 7 days, begin resolution within 45 days), and longer record-retention obligations. The federal regime builds prevention, response, and follow-up into one integrated process.
Investigator’s checklist
Mandate & issues defined
Interim measures in place
Notices to complainant and respondent
Evidence preserved (email, chat, CCTV, BYOD)
Interviews sequenced and completed
Findings on a balance of probabilities
Closure letters to both parties
Corrective and systemic actions implemented
Anti-reprisal reminder sent; monitoring set
Records secured and retained
Bottom line
A defensible investigation is timely, impartial, proportionate, and well-documented—and it communicates the outcome and corrective action to both the complainant and the respondent. Do those pieces well and you’ll meet your legal duties, protect people, and reduce litigation risk.