When a workplace complaint lands on your desk, it can feel like the safest option is to “start an investigation immediately.”  But in practice, that’s where many employers go wrong.  Some investigate when they shouldn’t. Others avoid investigating when they must. And many start the process without the structure needed to get a fair and defensible outcome.  Workplace investigations are one of the highest-risk areas for employers. Done properly, they protect your business. Done poorly, they can create more risk than the original complaint. 

Here are the most common mistakes I see — and how to avoid them. 

Mistake 1: Investigating Everything (or Nothing) 

Not every workplace issue requires a formal investigation. 

Some matters can and should be resolved quickly through clarification, coaching, or informal conversations. Jumping straight to a formal process can unnecessarily escalate the issue and damage working relationships.  On the other hand, failing to investigate when there are serious allegations — particularly where there are conflicting versions of events or potential misconduct — can expose your business to significant legal risk. 

The key question is not “should we investigate?” — it’s “what is the appropriate response to this issue?” 

Mistake 2: Choosing the Wrong Investigator 

One of the quickest ways to undermine an investigation is to appoint someone who is not truly independent or appropriately skilled. This often happens when: 

• the investigator has a prior relationship with one of the parties 

• the investigator is too junior or lacks experience 

• the outcome of the investigation could impact the investigator directly 

Even if the process is technically fair, a perceived lack of independence can undermine the credibility of the outcome.  In more complex or sensitive matters — particularly those involving senior employees or serious allegations — an external investigator is often the better option. 

Mistake 3: Getting Procedural Fairness Wrong 

This is where many investigations fail.  Procedural fairness is not just a legal concept — it’s a practical requirement. At its core, it means: 

• clearly putting allegations to the employee 

• giving them a genuine opportunity to respond 

• considering their response before making any decision 

Common mistakes include: 

• providing vague or incomplete allegations 

• making findings before hearing from the employee 

• not allowing a support person where appropriate 

• treating the process as a formality rather than a genuine inquiry 

Even where there is a valid reason for disciplinary action, a flawed process can undermine the outcome. 

Mistake 4: Poor Planning at the Start 

A rushed investigation is rarely a good investigation.  Before any interviews take place, there should be a clear plan that considers: 

• what exactly is being alleged 

• what evidence is available 

• who needs to be interviewed 

• the order of interviews 

• how confidentiality will be managed 

Without this structure, investigations can become unfocused, inefficient, and difficult to defend later. 

Mistake 5: Treating It Like a “Popularity Contest” 

A common trap is interviewing too many people — particularly those who did not directly witness the alleged events.  Good investigations focus on relevant evidence, not volume of opinion.  Interviewing unnecessary witnesses can: 

• delay the process 

• increase the risk of information spreading 

• introduce hearsay and inconsistency 

The focus should always be on who can provide direct, relevant evidence. 

Mistake 6: Failing to Make Clear Findings 

An investigation is not complete until clear findings are made. Sitting on the fence or simply summarising evidence is not enough. Each allegation should be assessed and a conclusion reached based on the evidence.  A well-drafted investigation outcome should: 

• clearly identify each allegation 

• assess the evidence logically 

• explain why findings have been made 

• state whether each allegation is substantiated or not 

This is critical if the outcome is later challenged. 

Mistake 7: Ignoring What Happens Next 

The investigation is not the end of the process — it’s the beginning of the next stage.  Even where allegations are not substantiated, there is often still a need to: 

• repair working relationships 

• address underlying team issues 

• provide support to employees involved 

Where allegations are substantiated, careful consideration must be given to: 

• appropriate disciplinary action 

• consistency with past decisions 

• risk of further claims 

Too often, employers focus entirely on the investigation itself and not enough on the aftermath. 

How Winter Workplace Consulting Can Help 

Workplace investigations are complex, high-risk, and often time-sensitive. 

At Winter Workplace Consulting, we support employers to: 

• assess whether an investigation is required 

• determine the most appropriate approach (informal, internal or external) 

• conduct fair and defensible investigations 

• manage procedural fairness and legal risk 

• navigate outcomes and next steps 

If you would like support managing a workplace complaint or conducting an investigation, please get in touch.