If the employer has decided to investigate a disciplinary or grievance issue, they should start as soon as possible.
This is to make sure they're treating the employee fairly. For example, people might remember a situation more clearly the sooner they're asked about it.
Who can carry out the investigation
Where possible, the employer should get somebody who's not involved in the case to carry out the investigation, for example another manager or someone from HR.
This is to keep things as fair as possible. In smaller organisations, the employer might have to do it themselves.
Where possible, the person investigating should also have had training. Acas offers training courses in handling disciplinary and grievance procedures, including courses on conducting investigations.
In a disciplinary case
In a disciplinary case, the employer should think about who will handle matters if further action is needed.
Where possible, a different person should handle each step of the disciplinary procedure that's needed:
- the investigation
- the disciplinary hearing and outcome
- the appeal hearing (if an appeal is raised)
Where possible, the employer should assign a more senior person to handle the disciplinary hearing and outcome than the person assigned to the investigation.
In a grievance case
For a grievance investigation, it is usually best for the person hearing the grievance to investigate the issue.
You can find more details on choosing who to carry out the investigation in the Acas guide to conducting workplace investigations.
Making an investigation plan
The employer and the person investigating, if there is one, should start by making an investigation plan.
This can include:
- what needs to be investigated
- who is carrying out the investigation
- 'witnesses' – anyone who needs to be spoken with to find out about the issue
- any sources of evidence, for example work records, emails or CCTV recordings
- any time limits, for example CCTV footage being deleted or staff going on leave
- timeframes
- policies or organisation guidelines to follow
- whether the person investigating is expected to give recommendations at the end of the investigation
- setting out the importance of confidentiality
- any other relevant points or information
A clear plan can help to:
- make the investigation as quick and easy as possible
- make clear exactly what needs to be done
- make sure the process is full and fair
- avoid negative effects on staff or the business
Employers and investigators can:
- find more details on making an investigation plan in the Acas guide to conducting workplace investigations
- download and use the Acas template for an investigation plan
Telling the employee
The employer or person investigating should tell the employee with the disciplinary or grievance issue as soon as they decide to open an investigation.
This is unless the employer thinks there is a risk that the employee might tamper with evidence or influence witnesses. In this case, the employer should wait until there is less risk of this.
When the employer tells the employee they are opening an investigation, it’s a good idea for them to explain:
- why they're carrying out an investigation
- who will be carrying it out
- what they're going to do
- that they'll need to talk to any witnesses
- how long it could take
- what will happen next, for example a meeting
- that everything will be kept confidential
Employers can use the Acas letter templates for:
- disciplinary cases – informing an employee they are the subject of an investigation
- grievance or disciplinary cases – inviting an employee to an investigation meeting
An investigation can be stressful for the employee in either disciplinary or grievance cases. It's important for employers to consider the wellbeing and mental health of their employees and offer support where needed.
Deciding whether to suspend an employee
If there's a serious issue or situation, an employer might consider suspending someone while they investigate.
An employer should consider each situation carefully. Suspension will only be needed in some situations.
If an employer feels they need to suspend someone, it's important to consider:
- alternative options to suspension
- the wellbeing of the person they're thinking of suspending – being suspended can be stressful and affect someone's mental health