Workplace Investigations Refresher Part 11: weighing evidence

By Jennifer Wyborn, Ashleigh Discipio and Caroline Beasley
23 Dec 2021
The more serious the allegation, the more probative the evidence should be to satisfy a conclusion on the balance of probabilities.


In the final article in our series on workplace investigations, we take a look at a critical part of the investigation process: weighing the evidence and making findings of fact in your investigation. We explore some of the key principles and two case studies which show how taking the time at this stage can make all the difference when seeking to rely on the outcome.

Key principles for weighing evidence

Once you have gathered evidence and provided the respondent with an opportunity to respond, the next step is to weigh up the evidence and make findings of fact on the matters investigated.

Standard of proof

When weighing evidence in a workplace investigation, there are two key principles to bear in mind:

  • The 'balance of probabilities' is the relevant standard to apply and is an assessment on whether the evidence supports that it is more likely than not that particular facts either occurred or did not occur. Where the evidence does not "tip the scales" in favour of a particular fact being established, then it is not proven.
  • The principles in Briginshaw v Briginshaw (1938) 60 CLR 336 require the more serious the allegations, which may lead to serious consequences for the employee (such as termination of employment), then the evidence relied upon needs to be of proportionately high probative value.

Workplace investigation best practice includes applying the Briginshaw standard to every investigation, regardless of the severity of the potential consequences for the respondent employee. Ensuring that only evidence of high probative value is relied upon in making any findings in an investigation to help to ensure the outcome of any workplace investigation is defensible if challenged.

Probative value principles

The probative value of evidence refers to the extent the evidence tends to persuade you of the truth of the allegation. Particular features of the evidence can affect its level of probative value, including:

  • whether the evidence is first hand or not;
  • whether the evidence is corroborated by other evidence; and
  • an assessment on the credibility of the source of the evidence, particularly in circumstances where the facts are contested and you have to form a view about which account you prefer.

Balancing these factors together will determine the probative value and the weight each piece of evidence should be given in reaching a finding in relation to an allegation, or justifying a reason for taking a particular action.

Other important factors in assessing evidence include:

  • The prejudicial nature of evidence:
    • Being unfairly biased towards a respondent can affect the strength of your evidence and findings. Always balance prejudicial evidence with its probative value. This often occurs where dealing with similar fact evidence. Similar fact evidence should be given less weight than evidence relating to the conduct which is the subject of the allegations.
  • Whether the evidence was legally obtained:
    • In Haslam v Fazche Pty Ltd T/A Integrity New Homes [2013] FWC 5593, the Fair Work Commission denied the use of audio recordings made by the employee in meetings had with her employers to demonstrate she had been dismissed and had not resigned. The recordings were not obtained legally or properly and so were denied.  More often than not, the Fair Work Commission will take a negative view of employees who engage in such conduct, noting that "it is seriously wrong and inexcusable… and a valid reason for dismissal" (Thomson v John Holland Group Pty Ltd [2012] FWA 10363).
  • Relevance of the evidence:
    • Best practice is to adopt the rules of evidence around admissibility, even though the same standard isn't required in a workplace investigation. This will assist you in relying on your findings if the outcome is challenged.

Case study: Bajelis

In Bajelis v Reserve Bank of Australia [2020] FWC 3740, Mr Bajelis' applied for an unfair dismissal remedy after his employment was terminated following his accidental sending of racist text messages to a work WhatsApp chat. Three minutes after sending the messages, another group member responded "I don't feel that this is a very appropriate thing to say or very polite", and within four minutes of sending the initial messages Mr Bajelis had identified what he had done, deleted the messages from the chat, and apologised, including stating: "I'm sorry to anyone who was offended".

Mr Bajelis' employment was terminated one month later following an internal investigation. The letter advising him of his dismissal set out reasons for the decision, including:

  • because of the fact the messages were sent;
  • because a number of employees found the comments offensive; and
  • because this fundamentally undermined Mr Bajelis' ability to have an ongoing working relationship with his colleagues.

Deputy President Cross found that there was insufficient evidence to support that:

  • "a number of employees" were offended; and
  • that Mr Bajelis had undermined ongoing working relationships by sending the messages.

To the contrary, the Deputy President was:

  • satisfied that the evidence supported there were only two employees who were offended, and one of these only found the messages to be impolite, which was less serious than being offended by the message.
  • not satisfied that there was any evidence that Mr Bajelis sending the messages had any impact on his ability to have a productive ongoing working relationship with his colleagues in the future.

Ultimately, Deputy President Cross ordered that Mr Bajelis be reinstated to his position and be compensated for the time between his dismissal and reinstatement date. This case demonstrates the importance of balancing your evidence and when placing weight, ensuring that there is sufficient evidence to support your decision.

Case study: Kelly v The Hills Christian Community School Inc

This case demonstrates how credibility of a witness can be the determining factor in forming a view about their evidence. Catherine Kelly was a Reception Teacher at the Hills Christian Community School. She was dismissed by the School because of an incident where she gave one of her students a birthday treat chocolate bar, and following this the student experienced an allergic reaction. This particular student had a number of allergies which were known to the School. Following an investigation of the incident, Ms Kelly's employment was terminated for serious misconduct on the basis of contravening the procedures in place regarding the student and the food they were supposed to eat at the School. Ms Kelly subsequently brought an unfair dismissal claim. Ultimately, Commissioner Platt ordered that Ms Kelly be reinstated because her dismissal was found to be unfair.

The decision came down to an assessment of the weight that was placed on different witness accounts of the handover process which took place between Ms Kelly and another teacher.

In relation to the incident, Ms Kelly maintained that she checked the ingredients in the chocolate bar, and was satisfied that, noting their allergies, the child could eat it, and that this was consistent with the process required to be followed for this student. Another teacher, Ms Romaldi, gave evidence that during a handover between the two teachers, she provided handwritten instructions to Ms Kelly to the effect that the student could only eat food that was supplied by the student's parents. Ms Kelly denied being told this, and stated the first time she was aware of that was in reading Ms Romaldi's statement during the course of the investigation conducted by the School. The question for Commissioner Platt to determine was whether Ms Romaldi's or Ms Kelly's evidence about the handover for the processes for the student should be preferred.

Commissioner Platt ultimately preferred the evidence of Ms Kelly because it was always consistent, and Ms Romaldi's evidence about the meeting referred to other matters which, when tested, were found to be not true. For example, Ms Romaldi said that the folder used in the handover was green, however a photograph of the folder which was in evidence before the Commission showed that the folder was red. Commissioner Platt observed that the internal investigation did not consider in detail the documents that were actually used in the course of the handover.

By preferring Ms Kelly's evidence over Ms Romaldi's, the outcome of the workplace investigation was cast into doubt, and Ms Kelly was reinstated. This case demonstrates how credibility can be used to support an investigator's decision to prefer the evidence of one witness over another, particularly in circumstances where there are two competing versions of events. (Catherine Kelly v The Hills Christian Community School Inc T/A The Hills Christian Community School [2018] FWC 4134)

Key points for workplace investigations

  • The more serious the allegation, the more probative the evidence should be to satisfy a conclusion on the balance of probabilities;
  • Consider all relevant evidence, and test any contradictory evidence;
  • When considering prior conduct, consider the prejudicial affect vs the probative value;
  • Where there is corroborating evidence, consider the possibility of collusion; always test the evidence;
  • When assessing credibility, identify your own biases, assess reliability and consistency and remember, everyone performs differently at interview;
  • The more thorough the investigation and weighing of evidence, the better chance of defending an unfair dismissal claim in the Fair Work Commission.

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Clayton Utz communications are intended to provide commentary and general information. They should not be relied upon as legal advice. Formal legal advice should be sought in particular transactions or on matters of interest arising from this communication. Persons listed may not be admitted in all States and Territories.