Acas has published new detailed guidance on conducting workplace investigations covering all aspects of the process, including how to choose the investigator and handling reluctant witnesses. A robust investigation process is the vital cornerstone of a reasonable disciplinary procedure and an essential element to obtaining a fair dismissal.

Investigations are fact finding exercises to collect information relevant to the matter at hand, helping an employer to gain a detailed picture of what happened and make an informed decision on how to move forward. They are most commonly used in the early stages of a disciplinary procedure when you have been alerted to the fact that misconduct appears to have arisen, but you need to find out more before starting a disciplinary procedure.

The main points of the guide are summarised below:

Role of investigator – The guidance states that the role of an investigator is to be fair and objective, looking at evidence that supports the allegation and evidence that contradicts it.

Length of investigation – This may be set out in contractual policies and procedures, in which case they should be followed. If no timescale is specified, you should provide the employee with a provisional timeframe within which the investigation will be completed. Complicated matters may take several weeks; other matters can be done very quickly and simply.

Who should investigate? – Usually, the employee’s line manager will be the appropriate person, however, when the matters are more serious or complex, someone more senior or experienced may be better placed. People who are personally involved in the matter; create a conflict of interest; may be involved in decision making later on or who have limited availability should be avoided.

Suspension – Employers should consider suspension during an investigation where the working relationships have broken down; if the employee may tamper with evidence; or there is a risk to people or property.

Investigation meeting – This is an opportunity for the investigator to interview someone who is involved in, or who has information on, the matter under investigation. A note-taker should be present and the meeting can be recorded if in the interviewee agrees or if the company’s policy allows.

Anonymous witnesses – investigators should try to avoid using anonymous witnesses wherever possible except for when the witness has a genuine fear of reprisal.

Retention of investigation report – the report should only be kept for as long as it is necessary, and disposed of once it becomes irrelevant or out of date.