Preparing the investigation report

A version of this article was first published in People Management in October 2025.

The final stage for the investigator will be to review the evidence they have collated to make their findings and to draw those findings into a written report. Much like the investigation plan, a well-structured report, addressing each of the issues investigated, will help to ensure conclusions and any recommendations are clearly formulated and justified. As the report is likely to be shared with relevant employees in later stages of the process and/or in an employment tribunal if a claim is brought, it plays a key role in demonstrating that a fair investigation has been carried out and that conclusions are well-reasoned.

Suggested structure for an investigation report

Whilst there is no prescribed format for an investigation report, the following structure is likely to be appropriate in most circumstances:

• Executive summary – summarising the scope of the investigation and summary findings
• Methodology – setting out:
  • list of witnesses interviewed
  • other evidence reviewed (e.g. documents, correspondence, CCTV)
  • policies referenced (e.g. disciplinary/grievance/whistleblowing policies and/or codes of conduct)
• List out issues under investigation – setting out under each:
  • the details of allegation or issue, with reference to scope
  • the relevant evidence relating to the allegation or issue
  • any material considerations relating to that evidence, for example, consistency of witness testimony, contemporaneous documentation, and any potential questions over the reliability of evidence
  • the application of the relevant sections of the policies
  • the findings relating to the allegation, including whether the facts relating to that allegation or issue are established or not. Where it is not possible to reach a conclusion, for example due to lack of evidence or diverging witness testimony, this should be acknowledged and explained.
• Overall conclusion(s) – referencing each allegation or issue, including the impact of any relevant mitigating circumstances (particularly relevant in a disciplinary investigation).
• Recommendations (if in scope).

Top tips for writing the report

1. Keep in mind who will read the report: Although circumstances will vary, the investigator should expect the report to be shared with others including potentially the individual(s) involved, and the disciplinary and appeals managers (if relevant).
2. Don’t go beyond the scope: The report should be proportionate to the issues being investigated, covering the key points but should not include unnecessary information or commentary. To help with this, the investigator should reference the scope of the investigation.
3. Clearly state conclusions and recommendations: The investigation report should draw clear conclusions, based on evidence, in relation to each allegation. In a disciplinary investigation, the investigator will establish the facts and, depending on the scope, may also be required to confirm whether there is a ‘case to answer’ – i.e. if the matter should be escalated to a formal disciplinary process. In a grievance investigation, the report should clearly set out whether the grievance is upheld, not upheld or partially upheld. Any mitigation that has been considered when reaching a conclusion should be explained. Where appropriate, for example in a grievance outcome, the investigator should also record any recommendations for further action, including formal or informal action.
4. Ensure conclusions are the investigator’s own: Whilst HR can support the investigator with how to structure and approach the drafting of the report, they should not influence the outcome or conclusions. Ensuring that the investigator has reached (and can clearly explain) their own conclusions will be essential in evidencing a fair investigation and potentially in defending any claims at a later stage.
5. Remember ‘paperwork’ may be disclosable: When drafting the report, the investigator should keep in mind that if the individual(s) concerned were to bring a claim, the report would almost certainly be disclosable in tribunal proceedings. As well as the final report, it is possible earlier drafts of the report may also be disclosable. The employee may request copies of the original drafts (potentially as part of a data subject access request or tribunal claim) so care should be taken. when creating and sharing drafts of the report. Other documentation, including notes made by the investigator, or emails with HR/other individuals regarding the investigation may also be disclosable.
6. Consider early legal advice: Depending on the circumstances, it may be sensible to seek legal advice in relation to an investigation. Doing so at an early stage can assist the investigator in testing the evidence considered, and the provisional conclusions reached. In some instances, early drafts of reports may be protected from being disclosable under legal privilege (however, whether a draft report attracts legal privilege will be fact specific and privilege is unlikely to attach to the report once finalised and released).

In summary, investing the time to produce a comprehensive, clear and structured report will be valuable in evidencing that an investigation has been fair and reasonable, and that the necessary investigations have been carried out to establish the facts of the case. From the employer’s perspective, this will help justify any further action that may be required and should reduce the risk of a successful appeal or tribunal claim. It also demonstrates to the employee that the employer has approached the matter seriously, invested time and resources, that their voice has been heard and that internal policies have been adhered to. This not only helps reduce legal risk but also builds employee trust.