Conducting workplace investigations is a critical responsibility for employers navigating allegations of misconduct, grievances, or policy breaches. Done correctly, investigations not only protect the business from legal exposure but also reinforce fairness, trust, and compliance in the workplace.
This guide outlines the legal principles, practical steps, and key considerations employers should understand before launching a formal investigation, drawing on relevant case law and best practice frameworks to help you make informed decisions.
What is a workplace investigation and what does it involve?
A workplace investigation is a structured process where an employer gathers facts about alleged misconduct, grievances, or other workplace concerns. It typically involves interviewing relevant parties, reviewing documents, and assessing evidence before deciding on next steps.
Why are they important for employers?
Investigations protect both the business and employees by ensuring decisions are based on evidence, not assumptions. Mishandling can lead to tribunal claims, reputational damage and potentially findings of unfair dismissal.
When should an employer consider launching a formal investigation?
Formal investigations should be considered when allegations involve misconduct, harassment, discrimination, whistleblowing, or breaches of company policy. Acas guidance stresses that even minor grievances may warrant investigation if informal resolution is not possible.
In Shrestha v Genesis Housing Association Ltd [2015], the Court of Appeal emphasised that employers must carry out a reasonable investigation, considering both incriminating and exculpatory evidence.
Incriminating evidence is material that points towards wrongdoing, such as witness statements confirming inappropriate behaviour or emails showing a breach of company policy.
Exculpatory evidence, by contrast, is material that clears the employee or provides an alternative explanation, such as records proving the employee was not present at the time of the alleged incident or documents showing compliance with procedures.
A fair investigation requires employers to weigh both types of evidence carefully. Ignoring evidence that may exonerate an employee risks the process being judged unreasonable, which in turn can lead to findings of unfair dismissal.
How does fairness underpin workplace investigations?
Fairness requires impartiality, transparency, and equal treatment. In British Home Stores Ltd v Burchell [1978], the Employment Appeal Tribunal established the “Burchell Test,” requiring employers to show they had a genuine belief in misconduct, based on reasonable grounds after a reasonable investigation. This remains the cornerstone of assessing fairness in misconduct dismissals in the Tribunal.
Practical Steps for Employers
1. Decide to investigate
Assess the allegation, consider informal resolution, and confirm the issue falls within misconduct, grievance, or policy breach scope. Record the decision to investigate and why.
2. Appoint an investigator
Select someone impartial and sufficiently senior, with no prior involvement. Confirm they have the time, skills, and authority to conduct the investigation.
3. Define scope and issues
Set clear terms of reference: what questions need answering, timeframes, confidentiality parameters, and who will be updated. Identify any immediate risks (e.g., safeguarding, data loss).
4. Plan the process and timeline
Map the sequence of tasks, witnesses, and documents to review. Set realistic deadlines, update parties, and agree a communications plan to avoid speculation.
5. Preserve evidence early
Secure relevant emails, documents, CCTV, access logs, and devices. Implement holds on deletion or auto-archiving. Note chain of custody for digital records.
6. Notify parties and manage interim measures
Inform the complainant and respondent of the investigation’s scope and process. Consider neutral temporary measures (e.g., suspension or adjusted duties) and explain reasons in writing.
7. Interview witnesses and parties
Prepare question plans, share appropriate information, and conduct fair, structured interviews. Allow the respondent to address each allegation and present exculpatory evidence.
8. Keep accurate records
Take contemporaneous notes, obtain signed statements where appropriate, and store records securely. Distinguish facts from opinion and label drafts vs final versions.
9. Evaluate evidence objectively
Test credibility and consistency, consider supporting and contradictory material, and identify gaps. Decide whether further inquiries are necessary before concluding.
10. Draft the investigation report
Produce a clear, factual summary: allegations, methodology, evidence, findings, and any recommendations. Attach relevant documents in appendices for transparency.
11. Submit report and separate decisions
Provide the report to the designated decision-maker (not the investigator). The decision-maker determines next steps, disciplinary action, mediation, training, or no further action.
12. Communicate outcomes
Notify relevant parties of the outcome (to the extent appropriate), record decisions, lift interim measures, and document any follow-up actions or learning for future practice.
How do you choose an investigator?
The investigator should be impartial, experienced, and capable of handling sensitive issues. Independence is critical, avoid appointing someone directly involved in the matter. Sometimes it may be necessary to use an external investigator.
Protecting Employees and the Business
Employers must balance the rights of complainants and respondents. Both should be given the opportunity to present their case, and neither should feel prejudged.
Confidentiality and impartiality
Limit information sharing to those directly involved. Impartiality can be reinforced by separating the roles of investigator and decision-maker.
Reluctant witnesses
Employers should reassure witnesses about confidentiality and explain the importance of their input. In some cases, written statements may be acceptable. However, if matters are to proceed to Tribunals witnesses may need to be identified.
Avoiding Pitfalls and Legal Risks
Legal risks of poor investigations
Flawed investigations can lead to claims of unfair dismissal, discrimination, or breach of contract. In Whitbread plc v Hall [2001], failure to properly investigate allegations contributed to a finding of unfair dismissal.
Similarly, Sainsbury’s Supermarkets Ltd v Hitt [2003] confirmed that tribunals should not substitute their own view of how an investigation should have been conducted, but employers must still act reasonably in the circumstances.
Importance of record-keeping
Accurate notes and reports provide evidence of fairness and compliance. They are vital if decisions are later scrutinised in tribunal proceedings. Taking attendance notes after making phone calls is a good way to keep a contemporaneous record.
Looking Ahead: Building a Stronger Framework
Managers should be trained in investigation techniques and supported by clear policies. This reduces inconsistency and strengthens compliance, while the support of solicitors can advise on complex or high-risk cases, ensuring compliance with employment law and minimising exposure to claims.
Balancing speed and thoroughness
Employers should also act promptly to maintain trust, but not at the expense of a fair and complete process. A rushed investigation risks errors and legal challenge.
When conducted with care, impartiality, and a clear framework, workplace investigations become a cornerstone of good governance and employee relations. They can protect all parties involved, reduce legal risk, and foster a workplace culture where accountability and fairness are front and centre.
For complex or sensitive matters, seeking external legal advice can help ensure compliance and mitigate risk. Our employment team supports employers with bespoke, expert advice that balances legal obligations with practical business needs, helping you manage challenges confidently and compliantly. If you need support, please don’t hesitate to contact our solicitors via the form below.
Conducting a Workplace Investigation: FAQs
When should an employer start an investigation?
An investigation should begin as soon as credible concerns arise that cannot be resolved informally. Acting quickly helps preserve evidence and demonstrates fairness.
Can an employee bring someone into an investigation meeting?
There is usually no statutory right at the investigatory stage, but many employers allow a colleague or trade union representative.
What is the investigator’s role?
The investigator’s job is to establish facts impartially and report findings. They do not decide sanctions or disciplinary outcomes.
What do you include in an investigation report?
A clear summary of the allegations, evidence gathered, witness statements and factual findings. Appendices should include supporting documents for transparency.
Can you refuse to take part in an investigation?
Employees can decline, but refusal may affect credibility. Employers should note the reasons and proceed with available evidence, ensuring fairness is maintained.
How long does an investigation take?
The timeframe depends on complexity, but employers should set a realistic schedule, keep parties updated, and avoid unnecessary delay.
What happens after the investigation?
The report is passed to the decision-maker, who decides whether disciplinary action, mediation, training, or no further action is appropriate.
Are the findings made public?
No. Findings remain confidential within the organisation and are shared only with those who need to know. However, they could be made public in legal proceedings.
Key Contact
Paul Hennity
Employment Law Partner
Paul is a Partner in our Employment Law team, currently dividing his time between our Chester and Wirral offices.
