3. Grievance Investigation

If an employee raises a grievance (formally or informally) you will need to investigate it to make sure you have all the facts.

Investigation may take many forms depending on the nature of the grievance. If the grievance is about a potential error in payments or holiday pay, investigation would involve checking payments. If there has been an error then correcting this by making a payment will resolve the grievance. 

Other types of grievance will require other investigation. Please review the guidance on investigation under disciplinary, as this will cover situations where you have to interview other employers and take witness statements etc.

Whatever the situation it is essential that all the information is gathered so that you can consider the grievance and make an informed and fair decision. The importance of investigation cannot be overstated. 

These guidance notes give an overview of the type of investigation that may be relevant in any situation. It also recommends how you document any investigation, which is important in order to demonstrate what has been done. 

Investigative Meeting

If an employee raises a grievance, the first step will normally be to arrange a meeting with the employee so that you can run through their grievance in more detail and make sure that you clearly understand the employees' grievance. This can be especially important when an employee raises a number of grievances.

You should aim to clarify and agree with the employee each grievance, so you can then investigate each one further. An employee will have the right to be accompanied at this meeting as it is a 'grievance meeting'.

You may want to discuss examples, times and dates, who witnessed any behaviour being complained about and gather as much information as possible. This will then allow you to decide how to investigate the allegations further.

It is always advisable to ask employees during such meetings how they would like the investigation to be progressed. Who would they like you to speak to, etc? (but it is ultimately for the employer to decide, e.g. if an employee make unrealistic requests regarding the investigation).

You should also ask the employee how they would like their grievance to be resolved / what outcome they are looking for. This can in some situations allow you to focus on the outcome, which may avoid having to carry out extensive investigation. For example, if an employee complains that a colleague has been rude to them, and they are looking for an apology, it may be possible to discuss this with the colleague who may accept that they may have been rude and may be willing to apologise. This would then save you having to potentially interview others who may have heard what was said. 

However, if the employee wants a work colleague to be sacked, this would need to be handled in a different way!

Documenting an Investigation

It is important to document how you have conducted the investigation. This will include:

  • Taking written witness statements from employees or others
  • Summarising who you have spoken to and when
  • Including any other written documentation (letters, emails)
  • Including any 'paperwork' that is relevant to the matter (e.g. audit trails, records etc)
  • Any additional meeting notes
  • CCTV.

Note: if an employee gives a verbal or written witness statement without you being present, it is strongly advised that you meet with the employee to go through what was said and document the meeting. This will demonstrate that you have not just taken a written or verbal statement at face value without questioning the individual.

Taking a witness statement:

When taking a witness statement, you can either:

Ask the employee to write out what they saw and witnessed. If so, ask them to include as much detail as possible including dates, times, places and confirm who else was present. You should then go through the statement with the individual and confirm any matters (you should make a record of this meeting and any additional notes). The employee should be asked to sign and date the witness statement once completed.

Alternatively, you can meet with the employee and go through what they saw and write out the statement for them. Again, ask details about times, dates and other witnesses. Once you have written out the statement, the witness should be asked to confirm it is a true reflection, and you should ask them to sign and date it. Make a note of the time and place when you met with the individuals, and keep any notes you take.


Anyone involved in the investigation (e.g. employees who may be interviewed / give witness statements), should be told that the matter is confidential.  You can also ask the to sign a confidentially agreement. This can help confirm what is expected, and it can also re-assure the employee who has raised the grievance that confidentiality will be maintained. This can especially be important in sensitive cases (e.g. harassment and discrimination).

Please refer to the guidance on investigation under disciplinary for further information.