Quick Answer
How do you investigate a sexual harassment complaint at work? Act promptly and protect the people involved, keep the matter confidential, and choose an impartial investigator. Interview the complainant, respondent and witnesses separately, gather other evidence, put the allegations to the respondent in writing, and decide each allegation on the balance of probabilities. Take proportionate action, never punish an honest complaint, and keep records of every step.
In this guide
Sexual Harassment Is a Serious Issue
Sexual harassment is a serious issue and will not be tolerated by those organisations that have a safe, inclusive, and respectful workplace culture.
If an employee, contractor, or volunteer has been found to have engaged in sexual harassment, it may be treated as misconduct.
In severe cases, sexual harassment can be considered a criminal offence.
Laws protect the rights of individuals to make sure a safe, inclusive, and respectful workplace.
Behaviour that is sexual harassment will lead to potential disciplinary action being taken, up to and including termination of employment.
Sexual Harassment and The Law
Laws apply to all workplaces, regardless of their size, geography, or industry in which they operate.
They protect employees, contractors, volunteers, customers, and visitors.
For example, in Australia, federal legislation includes the Australian Human Rights Commission Act 1986, the Sex Discrimination Act 1984, the Work Health and Safety Act 2011, and the Fair Work Act 2009.
There are also relevant work health and safety regulators and human rights and anti-discrimination agencies in all states and territories in Australia that have laws that apply to all workplaces in those geographies.
Investigating A Complaint of Sexual Harassment in The Workplace
A sexual harassment complaint may need to be investigated, and depending on the nature of the complaint, a formal determination about what has happened and any disciplinary action might be appropriate.
Where an investigation occurs, you must comply with your employer’s policy and notify human resources or a senior manager.
Step 1: Interview the Relevant Persons
All relevant persons will be identified and corresponded with as part of an investigation, including interviewing or inviting a statement or written response regarding the alleged breach.
Where interviews are conducted:
- The complainant, respondent(s), and witnesses will be interviewed separately.
- Records of the interviews will be documented.
- Requests made by a witness for the attendance of a support person at an interview will not be unreasonably refused.
Step 2: Obtain Other Facts
An employer can use reasonable means to obtain any other relevant facts as part of an investigation.
This may involve interviewing witnesses and examining evidence such as emails, internet content, social media sites, or camera footage.
During the investigation process, it is always important that:
- No assumptions are made that the respondent committed the conduct complained of or alleged.
- Confidentiality is observed, and disclosure is minimised when dealing with complaints.
- Any disciplinary action taken is proportionate to the conduct committed by the person found to have breached the policy and engaged in inappropriate conduct.
Step 3: Set Out the Allegations
In addition to writing out the allegations to the respondent, a summary may also be provided at an interview.
If the allegations are substantiated, the respondent(s) should be advised of the potential outcomes of the investigation.
Depending on the circumstances, including the seriousness of any allegation, the respondent may be stood down or suspended while the investigation is carried out. This is usually on full pay. Suspension without pay is only lawful in limited circumstances, such as where the employment contract, award or agreement allows it, so get advice before deciding.
However, you must consider other policy documents or the respondent’s employment contract before determining whether there are any restrictions upon the standdown.
Step 4: Deal with Unsubstantiated Allegations
Suppose an allegation is found to be unsubstantiated in that it is not sexual harassment and it is not in breach of your employers’ policy.
In that case, no further action will be taken against the respondent regarding the complaint.
In this case, the reason for the decision will be explained to the complainant and the respondent.
Step 5: Deal with Substantiated Allegations
If an allegation is substantiated, the possible outcomes could include, but are not limited to:
- Requiring an apology.
- Counselling or training.
- Undertakings as to agreed forms of future behaviour.
- Taking disciplinary action against the respondent, including issuing a warning, demotion, or termination of employment.
Where the disciplinary action may be termination of employment, separate written correspondence should be issued to the respondent to advise them that the allegations have been substantiated and provide written reasons for the substantiated findings.
The respondent may be invited to show cause as to why their employment should not be terminated in the circumstances.
The disciplinary outcome should be written to the respective parties, including the complainant.
However, due to privacy concerns, absolute disclosure of all matters may not be possible.
Step 6: Deal with False Allegations
Intentionally false allegations or those found unsubstantiated because they are frivolous or vexatious, should be viewed seriously.
Where found to be intentional or malicious, you may consider that disciplinary action should be taken, up to and including termination of the complainant’s employment, after a fair process. A complaint made honestly that is not substantiated is not a false allegation and must not be punished.
Step 7: Take Reasonable and Proportionate Actions
You must always exercise caution and common sense when dealing with incidents of sexual harassment or suspected sexual harassment.
Reasonable and proportionate actions depend upon the nature and seriousness of the conduct, which can include consequences for the complainant or the employer, including concerning workplace productivity.
When deciding on the appropriate disciplinary action, you may consider the following:
- the size and nature of the employer’s business or operations
- the available resources and budget
- practicability and the cost of a response.
To demonstrate compliance, it is important to maintain records showing the reasonable steps you have taken to prevent and respond to sexual harassment or suspected sexual harassment in the workplace. You should always consider and implement measures that promote safety in the workplace.
Before the Investigation Starts
- Safety and support first: Ask the complainant what they need to feel safe, such as changed rosters or reporting lines, and offer support such as an Employee Assistance Program.
- Choose an impartial investigator: Use someone with no conflict of interest. Consider an external investigator if the respondent is senior or the allegations are serious.
- Agree the scope: Write down the allegations to be investigated, the timeline and who will be told.
- Protect against victimisation: Make clear that anyone involved must not be treated badly for making or helping with a complaint.
How Findings Are Made
Workplace investigations are usually decided on the balance of probabilities, which asks whether it is more likely than not that the conduct happened. The more serious the allegation and its consequences, the stronger the evidence a decision-maker should expect. A lack of witnesses does not mean an allegation cannot be substantiated.
Investigations also support the positive duty under the Sex Discrimination Act, which requires employers to take reasonable and proportionate measures to eliminate sexual harassment. Our guide to sex-based harassment explains the related types of unlawful conduct.
| Document | Why keep it |
|---|---|
| Written complaint or file note of the verbal complaint | Shows exactly what was alleged and when |
| Interview notes signed or confirmed by each person | Records each account accurately |
| Letter setting out allegations to the respondent | Shows procedural fairness |
| Evidence collected, such as messages or footage | Supports the findings |
| Findings report and outcome letters | Shows the reasons for each decision |
Like To Learn More?
Our free webinar with Mills Oakley covers running investigations while minimising victimisation and psychosocial risk, along with the recent Victorian confidentiality reforms and current case law.
To learn more about supervisors’ and managers’ responsibilities regarding preventing and responding to sexual harassment in the workplace, please refer to the Sentrient Preventing and Responding to Sexual Harassment for Supervisors and Managers online course on our website.
To get a free demonstration of the prevention of and response to sexual harassment for supervisors and managers online course, please contact us today.
FAQs
1. How do you investigate a sexual harassment complaint at work?
Protect and support the people involved, choose an impartial investigator, interview the parties and witnesses separately, gather evidence, give the respondent a chance to respond, decide each allegation on the balance of probabilities, and take proportionate action.
2. Who should investigate a sexual harassment complaint?
Someone impartial with no conflict of interest and the skills to run a fair process. An external investigator is often better when the respondent is senior, the allegations are serious, or the business is small.
3. What standard of proof is used in a workplace investigation?
The balance of probabilities, meaning more likely than not. Serious allegations call for clear and convincing evidence before they are found substantiated.
4. Can a complainant stay anonymous?
Confidentiality should be protected as far as possible, but a fair investigation usually requires the respondent to know the substance of the allegations. Explain this to the complainant at the start.
5. What if the complaint is about a manager or the CEO?
Escalate it to someone more senior, such as the board, or use an external investigator, so the process is not controlled by the person accused.
Sources
Australian Human Rights Commission: Positive duty under the Sex Discrimination Act
Fair Work Ombudsman: Stand downs
Last reviewed: October 2026
