Choosing the wrong investigator is one of the fastest ways to derail a workplace investigation.
It can turn a simple issue into a complex one.
It can turn a fair process into a legal risk.
It can turn a complaint into a claim.
Across New Zealand and Australia, employers are required to ensure investigations are fair, unbiased and procedurally sound. That relies heavily on choosing the right investigator — not just the first available person or the one who “knows the people involved.”
The investigator you choose shapes:
- the integrity of the process,
- the safety of participants,
- the quality of findings,
- the organisation’s legal standing,
- and the trust your people have in the outcome.
Here’s the HR Unlocked guide to choosing an investigator who will protect fairness, credibility and your organisation.
1. Not every issue needs a formal investigation — start with triage
Before you even choose an investigator, you must determine if a formal investigation is the right pathway.
Use a preliminary assessment to decide:
- Is this misconduct, performance, or conflict?
- Is the issue substantiated enough to investigate?
- Is there risk to safety or wellbeing?
- Is there a pattern or history?
- Is mediation more suitable?
- Is an informal resolution appropriate?
Only move to formal investigation if it is:
- necessary,
- proportionate,
- and likely to lead to clarity.
Choosing the right investigator starts with choosing the right process.
2. Internal vs external investigators — what’s the difference?
Both can work well, but context matters.
Internal Investigator
Suitable for:
- low-risk matters
- simple fact-finding
- early-stage conduct issues
- clear, single-event allegations
- issues where parties trust the internal team
Benefits:
- cost-effective
- faster availability
- deep understanding of organisational context
Risks:
- perceived bias
- actual bias
- political pressure
- lack of expertise
- inability to manage complex interpersonal dynamics
Never use an internal investigator where bias is likely or where the issue involves senior leaders.
External Investigator
Suitable for:
- bullying, harassment or discrimination
- high-risk allegations
- serious misconduct
- employment relations authority risk
- senior staff or leadership issues
- multiple complainants or respondents
- historical allegations
- anonymous or multi-layered complaints
- conflict between staff and senior managers
- complex procedural fairness questions
Benefits:
- independence
- credibility
- expertise
- neutrality
- better defensibility in ERA/Fair Work Commission
- reduced internal politics
- experienced in interviewing distressed participants
Costs more — but reduces far greater downstream risk.
One HR Unlocked client put it simply:
“We stopped using internal people for sensitive matters because it created more conflict. Using external investigators restored trust immediately.”
3. Questions to ask when selecting an investigator
Whether internal or external, choose someone who meets these criteria:
✔ Do they understand employment law in NZ/AU?
You need someone who can apply:
- natural justice,
- good faith,
- procedural fairness,
- the balance of probabilities standard,
- privacy law,
- legal definitions of bullying/harassment/discrimination.
Expertise matters.
✔ Are they truly independent?
They must have no personal, professional or hierarchical connection that could influence the process.
If anyone involved could perceive bias → choose someone else.
✔ Do they have experience with sensitive interviews?
Interviewing:
- traumatised staff,
- distressed employees,
- vulnerable people,
- senior managers,
- reluctant witnesses
…requires skill.
Poor interviewing produces flawed findings.
✔ Can they communicate neutrally and clearly?
Investigators must:
- write logical reports,
- present evidence clearly,
- avoid emotive or biased language,
- explain complex findings simply,
- maintain confidentiality,
- avoid judgement.
✔ Do they understand workplace dynamics?
A great investigator understands:
- power imbalances,
- cultural contexts,
- team politics,
- retaliation risks,
- subcultures,
- union relationships.
Context shapes behaviour — and findings.
✔ Can they withstand pressure?
Investigations can get political.
You need someone who can:
- hold boundaries,
- resist influence,
- stay neutral,
- withstand pressure from leaders,
- manage expectations,
- keep emotional distance.
4. Red flags — do NOT choose an investigator who…
- already has an opinion
- knows the parties socially
- has previously been involved in the issue
- previously managed or coached participants
- is part of the leadership chain
- has a conflict of interest
- is too junior to handle the complexity
- cannot articulate a fair process
- uses punitive language
- promises outcomes
- suggests shortcuts
- is not trained
- has no investigator experience
- has a reputation for bias or “taking sides”
If you choose the wrong investigator, you can’t fix the process later.
5. Choosing between a “findings only” vs “findings + recommendations” investigator
Findings only
The investigator:
- determines what happened,
- assesses whether allegations are substantiated,
- analyses evidence,
- makes factual findings.
You make the decisions about consequences.
Best for:
- high-risk cases
- sensitive complaints
- senior employees
- legal defensibility
Findings + recommendations
The investigator also makes:
- recommendations about next steps,
- suggestions for workplace action,
- culture or safety adjustments.
Best for:
- lower-risk matters
- behaviour improvement
- culture improvement contexts
- conflict-based issues
Choose intentionally.
Be clear upfront about the investigator’s mandate.
6. Be clear about scope — before the investigator starts
The Terms of Reference (TOR) is the most important document in the entire process.
Your TOR should state:
- allegations being investigated
- what is in and out of scope
- definitions being applied
- evidence methods
- the standard of proof
- timelines
- reporting format
- confidentiality expectations
A well-scoped TOR prevents:
- bias
- scope creep
- wasted time
- flawed findings
- over-inclusion or under-inclusion
- employee confusion
Never let an investigator start without a TOR.
7. Communicate clearly with parties
When announcing who the investigator is, be transparent:
- why they were chosen
- their independence
- their role
- their mandate
- what the process involves
- confidentiality expectations
- support available
- next steps
Clear communication protects safety and psychological wellbeing.
8. The human side: investigations are scary for employees
Employees involved in investigations may feel:
- anxious
- intimidated
- confused
- scared
- defensive
- emotional
- embarrassed
A skilled investigator:
- explains each step clearly,
- avoids loaded questions,
- maintains neutrality,
- creates psychological safety,
- offers breaks,
- uses trauma-informed interviewing,
- avoids blame-based language.
One HR Unlocked client said:
“People told us they felt safe during the investigation — that’s how we knew we’d chosen the right person.”
Safety increases truthfulness and trust.
The bottom line
Choosing the right investigator is one of the most important decisions you will make when managing a complaint or allegation.
Across New Zealand and Australia, the safest and most effective approach is to choose someone who is:
- skilled,
- neutral,
- credible,
- trauma-informed,
- procedurally fair,
- aligned to natural justice principles,
- confident and calm,
- resistant to pressure,
- able to communicate clearly,
- experienced in complex HR matters.
Handled well, the choice of investigator protects trust, culture and legal defensibility.
If you want ANZ-ready investigator selection checklists, TOR templates, investigation frameworks and guidance on when to use internal vs external investigators, HR Unlocked gives you everything you need — without the consulting fees or the legal jargon.
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