When an employee allegation lands on your desk — misconduct, bullying, theft, safety breach, or policy violation — your next steps determine whether your business is legally protected or exposed. A workplace investigation is the structured process Australian employers use to examine allegations, gather evidence, and make defensible decisions before taking disciplinary action.

Learning how to conduct a workplace investigation in Australia follows a 6-step framework: decide whether to investigate, appoint an impartial investigator, gather evidence, conduct interviews, make findings on the balance of probabilities, and deliver documented outcomes. Every step must comply with procedural fairness under the Fair Work Act 2009, and the Fair Work Commission will scrutinise your process if the employee later claims unfair dismissal.

WHO needs this: HR managers, business owners, and franchise operators with 1–250 employees. WHAT it covers: the complete investigation process. WHEN to investigate: any allegation serious enough to warrant disciplinary action. WHERE it applies: all Australian workplaces under the Fair Work Act 2009. WHY it matters: the FWC overturns dismissals based on flawed process, with compensation up to $95,050. HOW: follow the steps below and speak to an employment lawyer early for complex cases.

When Does an Employer Need a Formal Investigation?

An investigation is warranted whenever an allegation, if proven, could result in a formal warning, suspension, or termination. Common triggers include bullying complaints, theft or fraud, safety violations, drug or alcohol use at work, policy breaches, and workplace conflicts that may escalate. Minor first-time issues can be managed informally, but if dismissal is a potential outcome, you need a formal documented process. Our workplace investigations service covers the full advisory framework for employers.

Step 1: Decide Whether to Investigate

Assess the complaint’s seriousness. If the likely consequence of a proven allegation is termination, suspension, or a formal warning, a formal investigation is required. Document your decision to investigate in writing, referencing the specific policy or conduct standard allegedly breached. If you decide not to investigate formally, record why — this protects your business if the complaint escalates later.

Step 2: Appoint the Right Investigator

The investigator must be impartial with no personal stake in the outcome. The FWC routinely overturns dismissals where the investigator had a bias or pre-judged the matter. For routine misconduct — attendance, minor policy breaches, performance concerns — an internal HR manager can investigate. For allegations involving criminal conduct, sexual harassment, fraud, or senior executives, engage an external investigator to ensure credibility if the matter reaches the FWC.

Step 3: Gather and Preserve Evidence

Evidence collection is the foundation of a defensible investigation. Gather all relevant materials before conducting interviews: emails, text messages, policy documents, employment contracts, performance records, CCTV footage, access logs, and witness statements. Preserve everything immediately — delete nothing. If electronic evidence is involved, restrict account access to prevent alteration. Catalogue each item with its date, source, and relevance. For evidentiary standards, refer to Fair Work Commission guidance on workplace investigations.

Step 4: Conduct Interviews Properly

Send the accused employee a formal letter stating the allegations, the policy allegedly breached, and the investigation process. Offer the right to a support person in writing — this is a requirement under section 387(d) of the Fair Work Act 2009. The Fair Work Ombudsman provides guidance on employer notification obligations.

Use consistent questions for all parties, take detailed written notes, and have interviewees review and sign them as accurate. Avoid leading questions — ask open-ended prompts like “Can you describe what happened on [date]?” rather than ones that suggest an answer.

Step 5: Make Findings on the Balance of Probabilities

Workplace investigations use the civil standard — more likely than not (over 50% probability) that the conduct occurred, not beyond reasonable doubt. Document findings for each allegation separately: substantiated, not substantiated, or inconclusive. Reference the specific evidence supporting each conclusion. Before finalising, share a summary with the accused employee and give them 3–5 business days to respond. This final right of response is critical — the FWC will overturn dismissals where it was denied.

Step 6: Deliver Outcomes and Document Everything

Communicate the outcome in writing. State each allegation and whether it was substantiated, the evidence relied upon, and the outcome — warning, suspension, termination, or no further action — with clear reasoning. Retain all records for a minimum of 7 years under Fair Work Act record-keeping requirements: the complaint, interview notes, evidence, responses, findings, and decision letter. These are your legal defence if the employee files an unfair dismissal claim within the 21-day window. See our HR best practice resources for retention guidance.

Common Investigation Failures

The FWCs most frequent process findings against employers: investigating to confirm a predetermined outcome (bias), refusing a support person, failing to provide written notice of allegations, skipping the final right of response, unreasonable delays exceeding 6 months, and inadequate documentation. Each can trigger an unfair dismissal finding with compensation up to $95,050 — half the $190,100 high income threshold from 1 July 2026. Even if misconduct is proven, flawed process means you lose. See our performance management guide for the disciplinary framework that follows investigations. For templates supporting your process, download our free employment documents.