Short answer: Ontario’s Occupational Health and Safety Act defines workplace harassment as a course of vexatious comment or conduct against a worker, including virtually through information and communications technology, that is known or ought reasonably to be known to be unwelcome, with a parallel definition for workplace sexual harassment. Two duties follow. Under s. 32.0.6, every employer needs a written harassment program, built in consultation with the joint health and safety committee, covering how complaints are reported, including around a supervisor who is the problem, and how they are investigated. Under s. 32.0.7, when an incident or complaint arises, the employer must ensure an investigation "appropriate in the circumstances" is conducted, and must inform the complainant, and the alleged harasser if they are a worker, in writing of the results and any corrective action. None of this is optional, and the enforcement backstop has teeth.
The duty, precisely
Three details in the statute catch employers off guard. First, the duty attaches to incidents and complaints: a formal complaint is not required, so an employer who becomes aware of potential harassment, through a resignation letter, an overheard exchange, an exit interview, owns the investigation duty already. Second, the definition’s reach is current: the "including virtually" language covers the group chat, the after-hours messages and the meeting-platform conduct as squarely as anything said in a hallway. Third, the written-results duty runs to both sides. The complainant and a respondent who works for you are each entitled to written notice of the results and of any corrective action, which means the investigation has to end in findings someone was willing to write down, a useful discipline to know about before you start.
What "appropriate in the circumstances" means in practice
The Act deliberately does not prescribe one procedure, and the phrase does real work: a shouting match between peers and a pattern of sexualized conduct by an executive do not need the same process, but both need a real one. In practice, appropriateness is measured on a few axes any adjudicator will recognize. Promptness: an investigation that starts months late has already made a finding about how seriously you took it. Impartiality: the investigator cannot be someone with a stake in the outcome or a reporting line through the respondent. Thoroughness: both parties heard, relevant witnesses interviewed, documents and electronic records gathered while they still exist. Documentation: contemporaneous notes, preserved evidence, a written report that shows its reasoning. And confidentiality handled honestly: protected as much as the process allows, never promised absolutely, because witnesses must be interviewed and results must be communicated.
Internal or external: the honest test
Most routine matters are properly investigated inside: HR or a trained manager, no conflict, documented process. The external cases select themselves once you ask who could conduct this impartially. When the respondent is senior leadership, an owner’s relative, or HR itself; when the complainant has already alleged the process is captured; when the facts touch potential criminality, fraud or safety threats; when litigation is clearly coming and the file needs to survive it; or when the workplace is small enough that everyone inside is a witness, a friend, or both. The Ministry’s backstop makes the same point from the other direction: an inspector can order a harassment investigation "carried out by an impartial person possessing such knowledge, experience or qualifications as are specified" at the employer’s expense under s. 55.3. Choosing your own impartial investigator, before the Ministry chooses one for you, is the cheaper and more dignified version of the same outcome.
The mechanics of a defensible file
A defensible harassment investigation looks the same as every defensible investigation we build: scope defined in writing before the first interview; parties and witnesses interviewed separately, with contemporaneous notes they can be shown to have made; electronic evidence, messages, schedules, access records, preserved early and handled with the chain-of-custody discipline described in our digital forensics guide; findings made on a balance of probabilities against the definition, not against vibes; and a report that separates what was found from what is recommended, because the employer, not the investigator, owns the corrective decisions. Where an external file is warranted, that is precisely the product of our workplace investigations practice, run with the procedural distance that lets your counsel rely on the findings, and paired where needed with the planning discipline in our high-risk termination guide when the outcome ends employment.
After the investigation
The written-results duty is the finish line the statute names: results and corrective action, in writing, to the complainant and to a respondent who is a worker. What the statute does not require is publishing the full report to the parties, and most careful employers communicate findings and outcomes rather than the raw file. Corrective action is yours to choose and should map to the findings, and the quiet obligations continue after the letters go out: monitoring for reprisal, which the Act separately prohibits, and revisiting the program under s. 32.0.6 when the file exposes a gap, an alternate reporting channel that did not exist, a supervisor who never got the training. An investigation that changes nothing structural tends to be an investigation you will run again.
Not legal advice
This article is general information about Ontario’s Occupational Health and Safety Act, not legal advice. Harassment matters carry employment-law, human-rights and sometimes criminal dimensions beyond OHSA; run significant files with employment counsel, and use an impartial investigator whose work your counsel can rely on.
Frequently asked questions
Does every harassment complaint require an investigation in Ontario?
Effectively yes, and more than complaints: OHSA s. 32.0.7 requires the employer to ensure an investigation appropriate in the circumstances into incidents and complaints of workplace harassment, so becoming aware of a potential incident triggers the duty even without a formal complaint. The depth of process scales with the circumstances; the existence of a real process does not.
Can we investigate a harassment complaint internally?
Yes, when it can be done impartially: a trained investigator with no stake in the outcome and no reporting line through the respondent, running a documented, prompt, both-sides process. External investigation is the honest answer when the respondent is senior, connected or in HR, when the file is headed to litigation, or when the workplace is too small for anyone inside to be impartial.
What do we have to tell the parties when the investigation ends?
OHSA s. 32.0.7(1)(b) requires that the worker who alleged harassment, and the alleged harasser if they are a worker of the employer, be informed in writing of the results of the investigation and of any corrective action taken or to be taken. That means findings and outcomes in writing, though not necessarily the full investigation report.
What happens if an employer fails to investigate properly?
The Ministry can intervene: under OHSA s. 55.3 an inspector can order a workplace harassment investigation conducted by an impartial third party with qualifications the inspector specifies, at the employer’s expense, on the employer’s clock. A deficient investigation also tends to surface later as evidence in wrongful dismissal, constructive dismissal and human-rights proceedings, which is usually the more expensive venue to discover it.
Sources
- Ontario, Occupational Health and Safety Act, s. 1 (definitions of workplace harassment and workplace sexual harassment), s. 32.0.6 (harassment program), s. 32.0.7 (duties re harassment), s. 55.3 (order for workplace harassment investigation). Accessed August 7, 2026.
- Ontario, Understand the law on workplace violence and harassment (Ministry guidance on the investigation and written-results duties). Accessed August 7, 2026.