Employment tribunals do not expect employers to conduct perfect investigations, but they do expect them to take reasonable steps to establish the facts before reaching conclusions. The principles set out in British Home Stores Ltd v Burchell (1978) confirm that, in misconduct cases, employers must form a genuine belief in wrongdoing based on reasonable grounds following a reasonable investigation.

At the heart of every investigation are the questions asked. The way those questions are framed determines the quality of the evidence obtained, the fairness of the process, and ultimately the robustness of the outcome. Poor questioning risks incomplete evidence, distorted accounts, and flawed decision-making. This article sets out key considerations to ensure investigations remain fair, structured, and legally defensible.

Ask Questions to Establish Facts - Not to Prove Guilt

Investigations must remain genuinely fact-finding exercises. Once an investigator approaches a case with a fixed view of the outcome, the integrity of the process is undermined. Employers should ensure investigators:

• Use open questions that allow individuals to describe events in their own words
  
• Explore all relevant evidence before drawing conclusions
  
• Remain open to alternative explanations and differing perspectives
  
• Avoid assumptions based on hearsay, speculation, or initial impressions
  
• Focus on gathering information rather than reaching outcomes
  
  

A useful test is whether the investigator would ask the same questions if the outcome were unknown. If not, the process risks becoming outcome-driven rather than evidence-led.

Give Employees a Genuine Opportunity to Respond

Fairness requires that individuals understand and are able to respond to the concerns raised about them. This is a core element of procedural fairness in any workplace investigation. Employers should ensure investigators:

• Clearly explain the purpose and scope of the investigation
  
• Provide sufficient detail for individuals to understand the concerns
  
• Allow adequate time for a full response
  
• Explore explanations, context, and mitigating factors
  
• Put relevant evidence to individuals where it may be relied upon later
  

An investigation loses credibility where individuals feel they were not properly heard before conclusions were formed.

Maintain Investigator Independence

The credibility of an investigation is shaped as much by who conducts it as by how it is conducted. Independence is central to maintaining trust in the process. Employers should consider:

• Appointing investigators with no prior involvement in the matter
  
• Identifying any actual or perceived conflicts of interest
  
• Ensuring the investigator has appropriate competence and authority
  
• Separating investigation and disciplinary decision-making roles where possible
  
• Using external investigators in higher-risk or sensitive cases

Where independence is unclear, the integrity of the findings may be called into question, regardless of the quality of the investigation itself.

Challenge Evidence Fairly and Consistently

Conflicting accounts are a normal feature of workplace investigations. The role of the investigator is to test evidence carefully while remaining neutral and consistent. Good practice includes:

• Using follow-up questions to clarify inconsistencies
  
• Exploring differences in accounts without confrontation
  
• Applying consistent scrutiny across all witnesses
  
• Separating factual evidence from opinion or interpretation
  
• Avoiding adversarial or cross-examination-style questioning

The investigator’s role is not to “disprove” individuals, but to understand what is most likely to have occurred based on the evidence available. It is important to remember that workplace investigations are not criminal proceedings. Findings are made on the balance of probabilities, meaning the investigator must assess which version of events is more likely, based on the totality of the evidence.

Keep Accurate Records of Questions and Responses

A fair investigation must also be a well-documented one. Records provide transparency, support decision-making, and are often critical if a decision is later challenged. Employers should ensure:

• Notes accurately reflect key questions and responses
  
• Records are objective and not selectively summarised
  
• Evidence is stored securely and consistently
  
• Investigation reports clearly explain reasoning and findings
  
• Conclusions are directly supported by the evidence gathered
  

Good documentation provides a clear audit trail and is often central to defending decisions under scrutiny.

Remember That Fair Process Matters

Even where allegations appear well-founded, process failures can still have legal consequences. The principles in Polkey v A E Dayton Services Ltd (1987) confirm that employers may face liability where a fair process has not been followed, even if dismissal would likely have occurred in any event. 

Employers can strengthen the robustness of their processes by:

• Following investigation and disciplinary procedures consistently
  
• Ensuring investigators are trained and impartial
  
• Communicating clearly throughout the process
  
• Maintaining appropriate confidentiality
  
• Ensuring all relevant evidence is considered before decisions are made
  

A defensible outcome depends not only on what decision is reached, but how that decision is arrived at.

In Summary

The quality of a workplace investigation is ultimately determined by the quality of the questions asked. Structured, impartial questioning enables employers to move from allegation to evidence, and from evidence to a fair and defensible conclusion.

When combined with a clear process, independent investigation, and careful assessment of evidence, effective questioning helps employers reduce risk, strengthen consistency, and build trust in workplace decision-making.