An organisation receives three written complaints alleging that an employee has engaged in workplace harassment.
The complaints describe inappropriate behaviour, swearing, verbal abuse and excessive shouting.
Management considers the complaints sufficiently detailed to proceed with an investigation. The investigator reviews the written accounts, puts allegations to the employee and ultimately makes findings of misconduct.
But there's one important step missing.
The investigator hasn't interviewed any of the complainants.
Is that necessarily a problem? If the complaints are already documented, what additional value would interviews provide?
A 2025 Fair Work Commission decision, [2025] FWC 2228, provides useful guidance about the importance of interviewing complainants and testing written allegations before making findings of workplace misconduct.
Three written complaints, but no complainant interviews
The case involved an employee working for an organisation that provided workplace drug and alcohol testing services.
Three colleagues complained about her conduct, alleging verbal harassment, inappropriate language, swearing and excessive shouting.
The employer received written accounts from two of the complainants, together with information about the third complaint relayed by a manager.
The employee was suspended while the allegations were investigated.
The employer subsequently concluded that she had engaged in verbal harassment and dismissed her.
However, when the employee challenged her dismissal, the Fair Work Commission identified a significant deficiency in the investigation.
The HR manager responsible for investigating the allegations and making the findings hadn't interviewed any of the three complainants.
Instead, the employer had relied on the written material without adequately examining its reliability.
The Commission found that this was unreasonable in the circumstances.
What could the complainant interviews have revealed?
This is the most interesting aspect of the decision.
The Commission didn't simply criticise the employer for failing to conduct interviews as a matter of process.
It identified specific information that those interviews were likely to have uncovered.
1. One complainant hadn't witnessed the alleged conduct
One of the complainants described inappropriate conduct towards two colleagues.
However, the Commission found that she hadn't actually witnessed the relevant conduct towards those employees.
An interview could have clarified which incidents she had personally observed and which matters she knew about through information provided by others.
That distinction was important when assessing the reliability and weight of her account.
The Commission also observed that examining workplace rosters could have assisted in establishing whether the complainant was present during the relevant periods.
This illustrates an important function of a complainant interview: establishing the source of the complainant's knowledge.
A person may genuinely believe that inappropriate conduct occurred without having personally witnessed it.
An investigator needs to distinguish between direct observations, information received from other people and conclusions drawn by the complainant.
2. Two complainants felt pressured to complain
The Commission also found that the other two complainants had felt pressured by the first complainant to make their complaints.
That information wasn't established during the employer's investigation.
The Commission considered that interviewing those complainants would have revealed the pressure they felt.
This was potentially significant when assessing the circumstances in which the allegations arose.
It doesn't mean their complaints should automatically have been disregarded.
However, investigators should understand whether a complaint was made independently, whether another person encouraged it and whether any relevant interpersonal conflict may have influenced the account.
3. The complaint itself raised questions about motivation
The Commission observed that the first complainant's written account disclosed that the respondent had previously complained about her.
This was an obvious matter for further enquiry.
An interview would have provided an opportunity to explore the relationship between the employees and whether the circumstances surrounding the complaint had any bearing on its reliability.
The investigator didn't pursue those enquiries.
As a result, potentially important information remained unexplored before the findings were made.
What did the Fair Work Commission say?
At paragraph [111], Deputy President Wright examined the employer's investigation.
The Commission found that the investigator hadn't interviewed the complainants, despite circumstances making further enquiries necessary.
It was particularly critical of the employer's claim in its termination letter that the credibility and sincerity of the complaints had been thoroughly assessed.
The Commission described that claim as:
"manifestly false."
The evidence didn't establish that such an assessment had occurred.
Instead, the employer had relied upon the complaints without adequately testing them.
The Commission concluded that the failure to interview complainants and the acceptance of their complaints at face value without further enquiry weighed in favour of finding the dismissal unfair.
The Commission also found that the alleged verbal harassment hadn't been established on the balance of probabilities.
The dismissal was ultimately found to be unfair.
Does this mean investigators must always interview complainants?
No. The decision does not establish a general legal rule requiring every complainant to be interviewed in every workplace investigation.
The Commission's criticism was directed at the circumstances of this particular investigation.
The complaints involved disputed conduct, questions about what witnesses had personally observed, possible pressure to complain and relevant workplace records that hadn't been examined.
There were significant matters requiring clarification.
In those circumstances, relying on the written material without conducting complainant interviews left important gaps in the evidence.
There may be other investigations where a detailed written statement, together with reliable documentary evidence, provides sufficient information to determine particular factual issues.
For example, a complainant might provide a detailed account of receiving an inappropriate email, together with the original email and associated communications.
If the facts are clear and undisputed, an extensive interview may add little.
However, where allegations depend substantially on witness recollection, credibility or disputed conversations, interviews are generally an important means of testing the evidence.
The question investigators should ask is whether the written complaint provides sufficient reliable evidence to make findings, or whether further enquiries are necessary.
What does an interview add to a written complaint?
Even a detailed written complaint may leave important questions unanswered.
Interviews serve several functions that are particularly relevant to assessing allegations.
Establishing precisely what the complainant alleges
Written complaints often contain general descriptions such as:
"The employee regularly bullied me."
Or:
"She was constantly aggressive and intimidating."
These statements describe the complainant's characterisation of the conduct.
An interview provides an opportunity to identify the actual behaviour alleged, including the words used, actions taken, approximate dates, locations and surrounding circumstances.
This information assists the investigator in identifying what must be proved.
Distinguishing observation from interpretation
A complainant may describe a colleague as angry, aggressive or threatening.
The investigator should establish what the complainant actually observed.
Did the person raise their voice? What words were used? Was there physical contact? How close were the individuals?
An interview can help separate the complainant's observations from their interpretation of the conduct.
This distinction can become particularly important when drafting allegations and assessing evidence.
Identifying inconsistencies or gaps
A written statement may contain apparent inconsistencies concerning the sequence of events, relevant dates or who was present.
An interview allows those matters to be clarified.
It also provides an opportunity to explore information that may appear significant but hasn't been adequately explained.
An investigator should avoid automatically interpreting inconsistencies as evidence of dishonesty. They may reflect differences in recollection, uncertainty or misunderstanding.
The purpose of further questioning is to establish a more reliable account.
Identifying additional evidence
Complainant interviews may reveal evidence that wasn't mentioned in the initial complaint.
This could include contemporaneous messages, emails, relevant records, disclosures to another person or additional witnesses.
The investigator can then consider whether those sources should be pursued.
In the 2025 decision, workplace rosters were an obvious potential source of evidence that could have tested aspects of the complaints.
Examining relevant context
A complainant's account may describe conduct without fully explaining the circumstances in which it occurred.
An interview allows the investigator to explore the relationship between the employees, their usual working arrangements, the context of conversations and any preceding events.
Context may affect how particular conduct should be interpreted.
It may also assist in identifying whether the evidence supports the allegation as framed.
What if the complainant has already provided a signed statement?
A signed witness statement can be important evidence.
The fact that it has been signed may help establish that the complainant has adopted its contents as their account.
However, a signature does not establish that the account is complete, accurate or sufficiently reliable to support every allegation.
The investigator still needs to consider whether material matters require clarification or testing.
For example, a signed statement may identify an incident but omit the exact words allegedly spoken.
It may describe conduct witnessed by several people without making clear whether the complainant observed it personally.
It may also contain conclusions about another employee's intentions without identifying the evidence supporting those conclusions.
In these circumstances, further questioning may be necessary.
An investigator might obtain clarification through a formal interview, a shorter follow-up discussion or written questions, depending on the circumstances.
The important consideration is whether the investigator has obtained and adequately assessed the evidence necessary to determine the allegations.
Are written questions an alternative to interviews?
In some circumstances, written follow-up questions may be appropriate.
For example, where a complainant has provided a detailed statement and only a small number of factual matters require clarification, written questions may be sufficient.
However, written responses can also leave further questions unanswered.
In a live interview, the investigator can explore an unexpected answer, ask the complainant to clarify an apparent inconsistency or follow a new line of enquiry.
That flexibility can be particularly valuable where allegations involve disputed conversations, conflicting witness accounts or significant credibility issues.
The method of obtaining evidence should be appropriate to the complexity of the matter and the enquiries required.
What should investigators do when a complainant refuses to be interviewed?
There may be circumstances where a complainant is unwilling or unable to participate in an interview.
That doesn't necessarily prevent an investigation from proceeding.
The investigator should consider the reasons for the refusal, whether alternative arrangements are appropriate and what evidence is otherwise available.
Possible approaches include offering a remote interview, arranging suitable support, obtaining written clarification or relying on other relevant evidence.
The investigator should document reasonable attempts to obtain the evidence.
Where a complainant's account cannot be adequately tested, the investigator must consider how that limitation affects the weight of the evidence and the findings reasonably available.
A refusal to participate doesn't automatically mean the complaint is false or incapable of substantiation.
Equally, the existence of a written complaint doesn't remove the need to assess its reliability.
Other procedural fairness concerns in the decision
Although the failure to interview complainants is the central lesson from this case, the Commission identified other deficiencies.
The employer hadn't provided sufficient particulars of the allegations to enable the respondent to meaningfully answer them.
It had also withheld the complainants' identities without adequately considering whether this would unfairly limit the employee's opportunity to respond.
There were additional concerns about the employer's refusal to allow the employee's preferred support person to attend disciplinary meetings.
These matters contributed to the Commission's overall conclusion that the dismissal was unfair.
They reinforce the importance of considering procedural fairness throughout an investigation and subsequent disciplinary process.
Frequently asked questions
Do you have to interview a complainant who has provided a detailed written complaint?
There is no universal requirement arising from this decision. However, an interview may be necessary where the complaint contains significant gaps, disputed factual matters or information requiring clarification.
Is a signed complaint sufficient evidence to substantiate misconduct?
A signed complaint is evidence, but its weight depends on its reliability, detail and consistency with other evidence. The investigator must determine whether the evidence as a whole supports the proposed finding.
Can an investigator rely entirely on written witness statements?
Potentially, depending on the circumstances. However, where credibility, disputed events or material inconsistencies are central to the allegations, failing to conduct further enquiries may substantially weaken the investigation.
Must investigators interview every witness named in a complaint?
No general rule requires every person identified in a complaint to be interviewed. Investigators should consider which witnesses may provide material evidence and make reasonable efforts to obtain that evidence.
What happens if the complainant cannot be interviewed?
The investigator should consider alternative ways of obtaining relevant information and assess whether the remaining evidence is sufficient to make findings. Any significant evidentiary limitations should be addressed in the analysis.
Final thoughts
The 2025 Fair Work Commission decision provides a useful reminder that obtaining written complaints and assessing their reliability are separate parts of the investigation process.
The employer had written accounts from employees alleging serious workplace misconduct.
However, it hadn't interviewed the complainants to establish what they'd personally witnessed, examine the circumstances in which the complaints were made or explore relevant inconsistencies.
Those enquiries were important because they were likely to have revealed information affecting the reliability of the allegations.
For workplace investigators, the practical question is straightforward:
Does the written complaint provide sufficient reliable evidence to determine the allegation, or are further enquiries necessary?
Where the allegations are serious, disputed or dependent on witness credibility, conducting a complainant interview will often be an important step in reaching a sound and defensible finding.
Insight Investigations provides independent workplace investigations, reportable conduct investigations and professional training in investigation practice.
For information about our investigation services and training, visit www.insightinvestigations.com.au.
Case reference: [2025] FWC 2228, Fair Work Commission, Deputy President Wright, 30 July 2025.