One of the toughest challenges in workplace investigations is when two parties give conflicting accounts of an incident and there’s little or no corroborating evidence. It’s a scenario often referred to as “he said, she said,”.

In these cases, the investigator’s role is not to prove beyond all doubt what happened, but to reach a conclusion on the balance of probabilities. The investigator has to decide which version of events is more likely than not, based on the evidence available. Not their opinion!

This is where I see a lot of investigators go wrong. They come to a conclusion based on their opinion. It is never the investigator's opinion that matters. It is the weight of the evidence. The question to ask is, on the balance of the evidence, which version of events is more credible.

I know this can be hard but this is what needs to be done. It ensures the investigation outcome is based on evidence and it protects the investigator. The investigator can confidently stand up and defend their findings by saying 'when I weighed up the evidence, there was more evidence to support the version of events told by X than Y' and so on.

So what can help keep investigators on track with he said/ she said scenarios?

1. Assess Credibility Systematically

• Credibility assessments should be methodical and documented. Factors to consider include:
• Consistency – Does the person’s account stay the same over time and across different settings?
• Detail – Is the account specific and plausible, or vague and changing?
• Corroboration – Even if there’s no direct witness, are there documents, emails, or indirect witnesses that align with their version?
• Motive – Could either party have a reason to fabricate or distort their account?

2. Look Beyond Witness Testimony

• Don’t stop with the primary accounts. Check physical or digital evidence – for example:
• CCTV footage
• Access logs
• Email or messaging records
• Meeting minutes or diary entries

Sometimes, small details from different sources can collectively tip the balance one way or another.

Also, ask yourself what evidence is missing which you would have expected to be there? For example, if it is alleged that there was a loud argument in an office it is likely someone would have heard it. If no witnesses heard any argument, that could support a version of events that the argument did not happen in the way described.

3. Avoid Assumptions About Behaviour

It’s tempting to assume that someone who hesitates or becomes emotional is hiding something – but this isn’t necessarily true. Cultural background, neurodiversity, and stress can all affect communication style. Base credibility decisions on factual inconsistencies, not on subjective impressions of behaviour.

4. Record Your Reasoning Clearly

When you make a finding in a “word against word” situation, explain exactly how you reached it. For example:

“Both parties gave conflicting accounts. However, Party A’s version was consistent across two interviews and supported by an email sent on the day in question, whereas Party B’s account changed significantly between interviews and was inconsistent with contemporaneous documentation.”

This transparency helps defend your decision if challenged

5. Accept That ‘Inconclusive’ Is Sometimes the Right Outcome

In some cases, there may not be enough evidence to make a definitive finding. While this can be frustrating, it’s better to record an “inconclusive” outcome than to make a conclusion that isn’t evidence-based. Decision-makers can then assess next steps based on organisational policies and risk appetite.

6. Training

Make sure investigators are trained. It is a tough job and can be lonely and stressful. Investigators need training in the process but also human skills. This is an area when law, process and human skills overlap and are equally important. That is why all our workplace investigators and trainers are also trained in the neuroscience of human performance by our Head of Neuroscience and Leadership Strategy, Clive Hyland. You need to understand what makes people tick to get the best out of them and we are always striving for best evidence.

Final Thought

Conflicting accounts are an investigator’s stress test. They demand careful evidence gathering, structured credibility assessment, and clear reasoning.

At Impact, our accredited workplace investigators are skilled at navigating these situations ensuring findings are fair, transparent, and defensible, even when the facts are in dispute.

If you would like a copy of our more detailed guide to conducing robust workplace investigations, please contact us as contact@impactlawyers.co.uk