It is  basic law that a  fair disciplinary dismissal must include a reasonable disciplinary investigation.  But what is that, exactly?  How much detail must you include in your investigation, how many witnesses must you interview, how far back do you have to go, how far must you challenge or test the evidence you accumulate?

In NHS24 v Pillar, the Employment Appeal Tribunal considered the question of detail. Ms Pillar felt the investigation report had been unreasonable because it had included reference to two Patient Safety Incidents (‘PSIs’)  similar to that which had led to her dismissal for gross misconduct, but neither of which had been made the subject of disciplinary action at the time.

As a result, she believed that the earlier PSIs were effectively “spent” or waived and so should not have featured in the investigation report at all.

The EAT rejected her argument.  It would be perverse to criticise the  employer on fairness because the investigation report included reference to something which was admitted to be relevant.

The judgment  provides some useful learning points for employers in its review of the authorities on the investigatory aspects of a fair disciplinary dismissal process.

What can employers learn?

When considering whether a particular disciplinary investigation was reasonable, the Tribunal should apply the “range of reasonable responses” test.

This recognises that every case will be different and that there are a number of approaches which an employer could take to it.  So long as you stay within that range, your investigation does not have to be perfect, procedurally flawless, police-standard, or even necessarily objectively correct in its conclusions.  The facts being investigated need only be established on a balance of probabilities (put crudely, 51% certainty) and not to the criminal standard of beyond all reasonable doubt (99%).

Things which may take an investigation outside that range of reasonable responses could include:

  • a failure to challenge obvious untruths or glaring inconsistencies
  • a deliberate pursuit of evidence in support of one party’s case rather than the others, or any other sign of over-bias or favouritism on the part of the investigator
  • the rejection of convincing evidence without explanation
  • the inclusion of material which is clearly prejudicial to a party but not even arguably relevant to the facts being investigated
  • not looking into or reaching conclusions on key allegations or not talking to clearly relevant witnesses
  • having the investigation carried out by someone criticised or incriminated by the employee whose conduct is the subject of the enquiry (although it may not be possible to avoid this in small businesses or at senior management levels)
  • not concluding the investigation within a reasonable period of time
  • referring to information which the employee had previously been told expressly would not be relied on in future, for example a warning which the employee had been told would be removed from his/her file on expiry. Here the EAT drew a distinction between that case and Ms Pillar’s, where the previous misconduct had led to some training but no assurances one way or the other about its future relevance

The EAT in Pillar reiterated  the responsibilities of the investigator and those of the manager making the dismissal decision. It is the investigator’s job to present the manager with a concluded view of the relevant facts, and the manager’s job to decide whether that view justifies dismissal.

So if as dismissing manager you are presented with an investigation report which contains material you think is irrelevant or otherwise inappropriate to rely upon, make sure that you explain in your own conclusions that you did not take any of it into account, but formed your decision instead on other stated grounds.

If you need guidance making sure an investigation is carried out correctly,  we are here to help.

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