A reasonable disciplinary investigation is a cornerstone of a fair disciplinary procedure. Without it, any related dismissal is likely to be deemed unfair by an Employment Tribunal.

Tribunals consider the principles derived from the case of British Home Stores Limited v Burchell [1978] IRLR 379, when considering the fairness of any dismissal.

To establish fairness in a conduct dismissal case, an employer must be able to demonstrate that at the time of dismissal:


  • It believed the employee to be guilty of misconduct;
  • It had reasonable grounds for believing that the employee was guilty of that misconduct; and
  • At the time it held that belief, it had carried out as much investigation as was reasonable in the circumstances.


From the outset, internal procedures should be checked for compliance with the relevant Acas   Code of Practice as this will be taken into account by a Tribunal when considering whether you have acted reasonably during the disciplinary process. Furthermore, non-compliance with the code can lead to increase in the amount of compensation by up to 25% in the event of an unreasonable failure to comply.

Here, we look at the key steps to follow in order to ensure reasonableness at the investigatory stage.


  1. Review and adhere to the internal disciplinary procedure as it relates to disciplinary investigations and ensure it complies with the relevant Acas Code of Practice.
  2. Assign responsibility for the investigation to someone unconnected to the allegations and who is less senior than the likely disciplining officer.
  3. Where this isn’t possible (e.g. due to the size of the company), consider appointing an external third party to conduct the investigation.
  4. Consider whether it is necessary to suspend the employee pending investigation.
  5. Minimise the period of suspension and keep the continued need for it under regular review.
  6. Conduct the investigation without unreasonable delay.
  7. Collate relevant documentary evidence at the outset of the investigation and continue to collect this as the investigation progresses.
  8. Interview the accused where the allegations at hand and documentary evidence available merit it.
  9. Interview witnesses to obtain their account of the incident or events and produce clear, intelligible and accurate contemporaneous notes and/or signed statements.
  10. Interviews should be held in private and the need for confidentiality should be observed by the interviewer / stressed to the interviewee.
  11. Although there is no statutory right to be accompanied at investigatory meetings, be mindful of any such right that may exist under your internal disciplinary procedure or through custom and practice.
  12. Minimise the scope for questions and questioning techniques being perceived as prejudicial – open questioning is preferable, i.e. who, what, when, where, how, why and attempts to put words into the mouths of interviewees should be avoided.
  13. Pre-empt employees refusing to sign the notes of interviews – ensure a record is made of the reason(s) why a signature is not forthcoming.
  14. Carefully consider whether to grant witness requests for anonymity – only in circumstances where the employee can reasonably demonstrate a genuine fear of serious reprisal should they be granted.
  15. Be prepared for employee non-cooperation with the investigation process and know how to respond (e.g. such non-cooperation could constitute a failure to obey a reasonable instruction which would justify disciplinary action in itself).
  16. Be aware of how to deal with counter-allegations and also the procedures involved (and/or your intended response) if an employee attempts to raise a grievance or counter-grievance during an investigatory interview.
  17. Know the internal policy as it relates to an employee recording his/her interview and convey this at the outset of the meeting.
  18. Where there is a criminal element to the allegations, know and adhere to the recognised internal procedure (e.g. as it relates to referring matters to the police, continuing to investigate internally etc.).
  19. Interview witnesses more than once if new facts or discrepancies arise.
  20. Prepare all notes / statements and relevant documentary evidence for consideration at the disciplinary hearing and provision to the employee in question in advance thereof


Chris Nagel, EML’s Director and Head of HR, comments…


“Despite the number of steps referred to above, disciplinary investigations are largely based on common sense. If you adopt a logical and diligent approach to the process, you won’t go far wrong. What’s more, you’ll provide your business with a sound basis on which to defend any related unfair dismissal claim.”