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Guide for business owners

How to Run a Fair Workplace Investigation

Behind almost every disciplinary or grievance that ends badly is a weak investigation. Get the fact-finding right and the rest of the process usually holds up. Get it wrong and even a fair decision can be picked apart later. Here is how to run an investigation that stands up, whatever comes next.

Written by Samantha Newton FCIPD, Chartered Fellow CIPD · 6 min read · Last reviewed June 2026

Samantha writes a weekly HR column for Health & Wellbeing Magazine.

Be clear what you're investigating, and why

Before you speak to anyone, write down the specific allegation or question you're investigating. A vague brief leads to a rambling process that misses the point and frustrates everyone involved.

Keep the scope tight. The job of an investigation is to establish the facts, not to reach a verdict. That decision comes later, and ideally by someone who hasn't run the investigation.

First move

Write down the exact allegation you're investigating before you start, and keep the scope tight.

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Gather evidence fairly and keep good records

Speak to the people involved and any witnesses, and gather any documents, messages or records that are relevant. Give the person under investigation a fair chance to put their side before any conclusion is drawn.

Take notes of every meeting, and keep everything confidential. Sloppy or missing records are one of the most common reasons an otherwise sound process falls apart later.

First move

Hear every side, keep the process confidential, and take proper notes of each conversation.

Stay impartial and produce a clear report

An investigator has to be genuinely impartial. If you're too close to the people or the outcome, appoint someone else, because a process that looks stitched up is worse than no process at all.

Finish with a clear written report that sets out what you looked at, what you found, and whether there is a case to answer. That report is what the decision-maker relies on, so it needs to stand on its own.

First move

If you can't be truly impartial, hand the investigation to someone who can, and finish with a clear written report.

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Key takeaways

  • A weak investigation undermines everything that follows, so it is worth doing properly.
  • Define the exact allegation and keep the scope to fact-finding, not judgement.
  • Hear all sides, keep records, and stay strictly confidential.
  • Use an impartial investigator and produce a clear report. Not sure where to start? Take the free Situation Check.

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