Circumstantial evidence is indeed admissible in disciplinary and arbitration hearings; that much we already know. However, certain important factors relating to the introduction of circumstantial evidence, and the manner in which it is to be dealt with, must be borne in mind.
So what is circumstantial evidence?
Circumstantial evidence is the opposite of ‘direct evidence’ (ie: the kind of evidence which comes from witnesses) and can therefore be described as ‘indirect evidence’ in that certain ‘assumptions’ are made. It is admissible under certain circumstances, and may only be used to support a substantial fact.
The Chairperson of an enquiry should listen to circumstantial evidence first and then decide how much weight they are going to give it (in other words, how fair it would be to admit it either entirely or in part).
Case law abounds with guidelines for the use of circumstantial evidence.
The leading case authority is R v Blom (1939 AD) wherein it was held that “The inference sought to be drawn must be consistent with all the proved facts. If it is not, then the inference cannot be drawn”.
This judgment continues that “The true facts should be such that they exclude every reasonable inference from them save the one sought to be drawn. If they do not exclude other reasonable inferences, then there must be doubt whether the inference sought to be drawn is correct”.
More recent landmark case law has also addressed circumstantial evidence.
In Atherstone v Lewis stores (Pty) Ltd [CCMA KNDB13032-11) it was noted that “The textbooks on evidence say that circumstantial evidence is persuasive if the inference sought to be drawn from the evidence is consistent with all the facts proved and it is the most plausible inference. It need not be the only inference”.
In practice, circumstantial evidence is used by way of proving certain facts, and thereafter seeking to persuade the chairperson/arbitrator, that the guilt of the employee is the most plausible inference that can be drawn from the proven facts.
In Komape v Spoornet (Pty) Ltd & others (labour Court: 2008) the Court held that in assessing circumstantial evidence, an arbitrator must always consider the cumulative effect of all the items of evidence before him or her, and that the onus in civil cases is discharged if the inference advanced is the mist readily apparent and acceptable from a number of other possible inferences.
The somewhat dated, but none the less still pertinent English case of Caswell v Powell Duffy Collieries Ltd  held that “There can be no inference unless there are objective facts from which to infer other facts which it is sought to establish … but if there are no positive proved facts from which the inference can be made, the method of inference fails and what is left is mere speculation or conjecture.
In short, circumstantial evidence must be based on proven facts which themselves lead to guilt being the most reasonable inference or assumption.
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