Who should carry out a disciplinary investigation?
There is no legislation on who should carry out a disciplinary investigation; the decision should be made on the basis of ensuring a fair investigation and avoiding any potential conflict of interest.
The investigation should be carried out by a management representative who is not the person who will conduct any resulting disciplinary hearing. This will not always be possible, for example in very small organisations. The Acas code of practice on disciplinary and grievance procedures states that different people should carry out the investigation and disciplinary hearing "where practicable".
The person carrying out the investigation should not be involved in the matter in question in any way, for example as a witness. To avoid any suggestion of bias, the investigating officer should be someone who is not in the employee's direct line of management, if this is practicable.
Ideally, the investigating officer will have received training on how to carry out a disciplinary investigation.