When to appoint an external workplace investigator

Whether to handle a workplace investigation internally or appoint an external investigator is one of the most consequential decisions in complaints handling. The choice shapes how the matter is perceived by participants, how robust the process is to later challenge, and how much organisational capacity is consumed in delivering it.

The decision should be made deliberately, against a documented framework, rather than defaulting to whichever option is most familiar. Both internal and external investigations can be effective when matched to the right matter.

External appointment is generally appropriate where the matter involves senior leaders, where there is a perceived or actual conflict of interest, where the subject matter is particularly sensitive, where internal investigative capacity is limited, or where the credibility of the process to participants would be supported by an independent investigator.

External appointment is also appropriate where the matter is likely to involve complex evidence handling, where the consequences for participants are significant, or where the organisation has been criticised in the past for the handling of similar matters.

Independence is the central reason external investigators are appointed. The terms of reference should make the scope, the questions to be answered, the standard of proof to be applied and the reporting expectations explicit before the work begins. Ambiguity in any of these areas creates risk during and after the investigation.

Terms of reference should also address practical matters: timelines, access to documents and witnesses, interaction with other processes such as workers' compensation or police involvement, and how findings will be communicated to participants.

Procedural fairness obligations apply to external investigations in the same way as internal ones. Respondents are entitled to know the substance of allegations and to have a genuine opportunity to respond. Witnesses are entitled to support arrangements and clarity about how their evidence will be used.

Evidence handling — interview notes, document collection, contemporaneous records — should be disciplined throughout. The investigator's report is only as defensible as the evidence record that supports it.

The investigator's report should set out the allegations, the evidence considered, the findings made on the balance of probabilities, and the reasoning for each finding. Decisions about consequences are a matter for the employer, informed by the findings but separate from them.

Post-investigation steps — communication with participants, action on findings, support arrangements, systemic learning — should be planned before the report is delivered, so the organisation is ready to act on its conclusions.

AWS provides external workplace investigation services and also supports employers in designing internal investigation frameworks, deciding when external appointment is appropriate, and reviewing investigation outcomes for procedural and substantive quality.