It is a basic plank of a fair disciplinary dismissal that it be preceded by a reasonable investigation. But what is that, exactly? How much detail must you include in your enquiry, how many witnesses must you grill, how far back do you have to go, how far must you challenge or test the evidence you accrue?

In NHS24 –v– Pillar last month the Employment Appeal Tribunal considered the detail question, but on the unusual premise that the investigation report contained too much of it, rather than not enough. In particular, said Ms Pillar, the investigation report had been unreasonable because it had included reference to two previous incidents of conduct 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 contended that those incidents were effectively “spent” or waived and so should not have featured in the investigation report. Potentially a nice argument, but immediately and obviously undermined by her concession that in fact those previous incidents were relevant material for the employer to have in mind when considering what to do about the third and most recent incident.

The EAT rejected her proposition in fairly short order. It would be perverse to put the employer down on fairness because the investigation report included reference to something which was admitted to be relevant. No big surprises in that outcome, therefore, but some useful learning points for employers were made in the EAT’s review of the rather limited authorities on the investigatory aspects of a fair disciplinary dismissal process.

Lessons for employers

  • 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 (not least in terms of the questions in the opening paragraph) which could all be equally legitimate. So long as you stay within that range, therefore, your investigation does not have to be perfect, procedurally flawless, police-standard, or even necessarily objectively correct in its conclusions. Remember that 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 seemingly cogent 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;
    • (although it may not be possible to avoid this in small businesses or at senior management levels) having the investigation carried out by someone criticised or incriminated by the employee whose conduct is the subject of the enquiry;
    • not concluding the investigation within a reasonable period of time – this does not require speed above substance, but it would certainly be best to avoid long gaps in the process where nothing is seen to be happening;
    • 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.
  • Acas provides some guidance to employers as to the format which an investigation report could take but this is an area where the substance of your conclusions is much more important than the form of them. That said, the more the investigator explains what he/she has done and why, the harder it will be for an Employment Tribunal to argue that the finished product falls outside that range of reasonable responses.
  • In particular, the EAT in Pillar dusted off the often-forgotten line between the responsibilities of the investigator and those of the manager making the dismissal decision. It is the former’s job to present the latter with a concluded view of the relevant facts, and the latter’s job to decide whether that view justifies dismissal. It is therefore largely what the latter takes into account which makes the dismissal fair or unfair, and so it would not generally matter if the investigation report did contain some small level of extraneous material, so long as he/she did not rely on it to the employee’s detriment.

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.