The Adverse Inference Principle
Posted: Sat Nov 08, 2025 9:55 am
Definition
1.
An adverse inference is a discretionary1 tool available to tribunals, and a remedy for the parties to seek, to discharge a party from its burden of proof in the face of non-disclosure of evidence by the opposing party (see also Document production). This tool is usually employed when a party is silent or fails to disclose despite having the obligation or being ordered to do so.2
The legal rule of evidence that applies when a party fails to produce the best evidence is related to the adverse inference principle. The court may, at its discretion, draw an adverse (unfavourable) inference that the reason for the absence of the evidence is that it would have been unhelpful or contrary to the party's case.
The Best Evidence Rule
The "best evidence" rule, in its traditional and narrow sense, generally applies to documentary evidence and requires a party to produce the original document to prove its contents. If the original is available, a copy is typically not admissible unless the original's absence is satisfactorily explained (e.g., it is lost, destroyed, or in the possession of the opposing party who refuses to produce it after notice).
The Adverse Inference Principle
The broader principle related to the failure to produce any material evidence (documents, physical evidence, or a key witness) that is within a party's control is the adverse inference principle. This is not a strict rule of exclusion, but rather a matter that affects the weight or importance the judge or jury gives to the evidence presented.
The court may draw an adverse inference if:
The evidence or witness is material to a key issue in the case.
The evidence or witness is within the exclusive control of the party failing to produce it.
The party fails to provide a legitimate, plausible explanation for the non-production.
Essentially, the court presumes that a party who fails to "flaunt" available, material evidence does so because that evidence would likely be unfavourable to their position. The court considers all the circumstances of the case before deciding whether drawing such an inference is warranted.