Grievance Investigations Guide

  • Grievance
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Peninsula Group, HR and Health & Safety Experts

(Last updated )

If you’re investigating an employee grievance, you must make sure your procedure is fair. We explain the correct process, along with the employment laws to follow.

It’s a legal requirement for your business to have a grievance procedure. It explains the process an employee must follow to make a complaint about your business or a colleague.

After you receive a complaint, you’ll need to decide if you need a grievance investigation from a manager. It’s important to find out all you reasonably can do about the problem.

Remember, it’s an important employment law issue to get right. You can call us on 0800 028 2420 for immediate support and guidance with your investigation’s procedures.

You can also read this guide for important step-by-step information.

Why you need a grievance investigation

No matter the type of grievance, you’ll need to investigate it. This is to:

  • Make sure it’s a genuine complaint.
  • Ensure consistent and fair treatment for all staff.
  • Gather all suitable evidence.
  • Explain your procedures to the employee as they move along.
  • Determine if the formal procedure must continue.
  • If you can conclude the investigation informally.

For example, if it’s a bullying grievance investigation then your approach must remain as fair and consistent as with other complaints you receive.

If you don’t conduct an investigation, then the decisions you make will likely be unfair. This is a flawed grievance investigation.

An unfair grievance investigation could result in legal action, such as an employment tribunal.

You can avoid this outcome by following your business; procedures and taking suitable steps to follow a fair process.

How to investigate a grievance

After an employee raises a complaint, it’s your duty to examine the available evidence through your grievance investigation process.

If you’re conducting a grievance investigation you can refer to this grievance investigation template:

  • Select an appropriate manager to investigate the situation.
  • Create an investigation plan.
  • Develop investigation meeting questions (more on these further below).
  • Conduct interviews.
  • Gather all other available information.
  • Hold a grievance hearing.
  • Close the investigation.
  • Make your decision.

Keep the following steps in mind for your grievance investigation procedure:

  • Remain fair and objective throughout your procedure.
  • Follow your business’ guidelines and policies.
  • Gather as much information about the complaint as possible. This may include speaking to anyone directly involved,
  • Don’t aim to prove an individual guilty, you’re looking for genuine evidence from all sides.
  • Maintain confidentiality at all times.
  • Provide updates when necessary to individuals involved in the case.

Gathering physical evidence may prove a big part of your procedure. This depends on the types of information you have available to you.

Here are examples of information you can source:

You should always follow UK employment laws throughout an investigation. You may also need to refer to an employee’s contract of employment to check the terms and conditions of their role.

Throughout a grievance complaint, you must look to provide a fair procedure. Your investigation is a big part of this.

So, there’s a requirement you respect the Equality Act 2010 and not discriminate against any employees.

Additionally, you should follow the Data Protection Act 2018 and the principles it lays out. 

Based on the above, it’s good business practice to look for evidence to see if there is an issue you need to address. The goal of the investigation isn’t to prove an employee’s guilt.

Examine the information available to you and make your decision. You’ll need to inform the individuals in the case of your what you decide upon.

After this, your employee has the right to appeal your decision about their complaint.

Holding a grievance investigation meeting

You might need to get information from the employee, their colleagues, and any witnesses. So, you may need to hold multiple meetings to gather evidence.

for investigation hearings. However, it’s good business practice to allow your employee to have this option.

They is a legal right for them to be accompanied by a colleague or trade union representative for a grievance hearing, however.

During the meeting, you should ask relevant questions that are fair—what you ask needs to determine facts about a specific complaint.

As such, important grievance investigation questions to ask include:

  • Where and when did the issue take place?
  • Who committed the alleged incident?
  • When did the incident happen?
  • Who was present during the incident?
  • Do you think this incident affects how you perform your job?
  • Do you have any physical evidence about this incident?
  • What action do you want the business to take?
  • Is there anyone else who may have relevant information?

Remember, a complaint could be for a wide variety of reasons. You’ll need to tailor your grievance meeting questions to suit the issue you’re dealing with.

Sample invite to a grievance investigation meeting letter

If you’re conducting meetings to gather information about a complaint, you should inform employees in the case about this in writing.

Your letter will need to address the following:

  • The date and time of the meeting.
  • Who will be present.
  • What the grievance complaint is.
  • Why the employee needs to attend.
  • A request the employee brings any relevant information with them.
  • Alternative arrangements if the initial date isn’t suitable.

Please note, you should adapt your template to meet your business’ requirements. Each grievance complaint will need specific details.

How long should a grievance investigation take?

So, how long does a grievance investigation take? Ideally, you should complete it as quickly as you can. This is as long as you can maintain a fair process throughout.

However, the length of the investigation depends on what the complaint is.

Some issues may take longer to examine than others. One issue may take a day to cover. Another may take a week or longer.

The individual managing the grievance complaint can lay out a timescale based off the information they have available.

In your written grievance procedure, you should also explain how long the investigation will take. And how you’ll inform the individuals involved.

Grievance complaints at unusual times

Your business may receive a grievance complaint at times that seem inappropriate. For example, during a redundancy process. Consulting redundancy advice can clarify whether this is inappropriate.

However, it isn’t uncommon for employees to make a complaint at such a time. It can happen for many reasons. For example, if an employee has an issue with the reason for their dismissal.

Another example is a grievance during a disciplinary investigation. Depending on the nature of the complaint, you may want to put your disciplinary procedure on hold until the grievance is over.

Need our help?

We’ll guide you through the steps you need to take in a grievance investigation. Get in touch for immediate support: 0800 028 2420.


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