I Wonder How to Conduct an Internal Investigation Properly?

Internal investigations are a vital part of fairly managing workplace issues. Whether dealing with allegations of misconduct or grievances, a thorough investigation is essential.

It helps establish the facts, supports informed decision-making, and ensures employees’ rights are respected throughout the process. It can also be the case that, during a disciplinary investigation, perfectly plausible explanations emerge and the disciplinary process is discontinued without a hearing. This is why it is of vital importance that, even in cases of apparently “obvious guilt”, the employer should always investigate rather than launch straight into a disciplinary hearing or (worse) go straight to dismissal.

This article provides an overview of how to conduct an internal investigation properly.

Understanding the Need for an Investigation

Internal investigations are usually triggered by allegations of misconduct or workplace grievances. Employers must ensure they follow a fair procedure in such cases, and investigations are a crucial part of this. These investigations are covered by the ACAS Code of Practice on disciplinary and grievance procedures. While an organisation may have its own policy or procedure for investigations, it should adhere to the code as a minimum standard because the Employment Tribunal will consider this when assessing whether an employer has acted reasonably. Following the Code helps ensure investigations are thorough, impartial, and transparent. Failing to carry out a reasonable investigation can have serious consequences, and any decisions made in such cases are likely to be deemed unfair, potentially leading to legal action.

If the employer decides to initiate an investigation into a disciplinary or grievance issue, they should do so as soon as possible following the alleged incident or receipt of the grievance. Contemporaneous evidence (records, documents, or recordings made at or near the time of an event) is given greater weight in legal proceedings because it is generally considered more reliable, authentic, and less tainted by hindsight than later recollections.

Planning the Investigation Process

Effective planning is the foundation of any internal investigation. The steps outlined below provide a structured approach to planning an investigation:

• Establish a Clear Investigation Plan – Outline the steps, key actions, and timelines to keep the investigation organised and efficient.
   
• Set the Investigation Parameters – Clearly identify the specific allegation or complaint. Understanding the nature of the issue, whether it relates to misconduct or a grievance, is crucial for setting the direction and focus of the investigation.
   
• Appoint the Right Investigator – The investigator should be impartial, objective, and free of any conflict of interest (i.e., they should not have witnessed or been involved in the alleged incident). Ideally, they should have experience in handling internal investigations and be familiar with the organisation’s investigation policy. For serious or complex cases, it may be appropriate to appoint an external investigator to ensure complete objectivity and minimise the risk of bias.
   
• Evidence – Identify and review necessary evidence in advance. Preparing and reviewing evidence in advance allows the investigator to identify gaps, formulate questions, and ensure the investigation is comprehensive.
   
• Confidentiality – To protect the integrity of the process and the privacy of those involved, ensuring that all information related to the investigation remains confidential.
   
• Communicate the Process to All Parties – Inform the complainant, the accused, and any witnesses about the investigation, what to expect, and the timeline. Ensure they understand their roles and rights to maintain transparency and fairness.
   
• Set Realistic Timeframes - Assign reasonable deadlines for each stage, consider case complexity, and communicate any delays.
   
• Suspension – In serious cases, an employer may suspend an employee while the investigation is underway. This decision should be made carefully, as suspension should be considered a last resort and is only appropriate in certain situations. Alternative measures and the employee’s wellbeing should also be taken into account.

Conducting the Investigation

Gathering and Reviewing Evidence
The investigator should gather all information reasonably required to support the case, including witness statements, emails, documents, CCTV footage, or other relevant materials. Care must be taken to comply with legal requirements, such as data protection, and to keep a clear record of the source and handling of all evidence to maintain its integrity.

Interviewing Relevant Parties
Interviews are a key part of any investigation. The investigator should speak to all parties and relevant witnesses, conducting each interview impartially and professionally. If a witness requests anonymity, this must be considered and provided where possible.  All witnesses should be instructed not to discuss the investigation with anyone else.

Documenting the Investigation
Keep accurate, detailed records of all interviews and evidence, including dates, times, participants, and key points. Proper documentation is essential, as it underpins the investigation report, supports decisions, and may be relied upon in any legal proceedings.

Maintaining Confidentiality
Maintain the confidentiality of all participants and evidence, sharing information only on a need-to-know basis to prevent misunderstandings and preserve trust.

Prepare a Report
The final step in an internal investigation is to draft a concise report for decision-makers. The report should clearly outline which facts have been established and which are in dispute. If it has been agreed that the investigator should also provide recommendations for next steps, these should be clearly presented in the report.

Conclusion

Conducting an internal investigation properly is vital for maintaining fairness, transparency, and legal compliance in the workplace. A careful investigation not only protects employees but also safeguards the organisation.

Further Advice

If you have any queries on internal investigations or any other employment-related matters, our Peace of Mind Team is here to provide expert guidance. Our Document Audit Team can also assist in drafting relevant workplace policies.

Contact our Employment Team by emailing employment@warnergoodman.co.uk or calling 023 8071 7717.

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