Last Updated: August 22 2026
In Ontario civil disputes, can a court draw an adverse inference when a party fails to produce key evidence or testify?
Yes. In Ontario civil cases, an adverse (negative) inference may be drawn when a party fails to produce relevant evidence or documents they were required to produce, or fails to testify or call a material witness they were reasonably expected to provide, unless there is a legitimate explanation or the evidence was equally available to both sides, or the witness was not within the party’s exclusive control; courts treat the inference as discretionary and look at the case-specific circumstances. In Tiwari v. Chevalier, 2022 ONSC 3071, and Lane v. Kock, 2015 ONSC 1972, the court describes how the failure to produce expected evidence can support an inference that the evidence would be unfavourable. If you are dealing with missing documents, a witness who was not called, or a lack of affidavit evidence in an Ontario matter, paralegal KLP Paralegal Services can help you assess whether to seek or respond to an adverse inference and how to frame the explanation; call (416) 570-6378 to discuss next steps.
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Understanding the Principle of Adverse Inference as an Evidentiary Rule Arising from Failure to Produce Evidence
An adverse inference, which may sometimes also be called a negative inference, may occur a litigant fails to provide evidence or fails to provide testimony that was reasonably expected to come from the litigant. Where the litigant fails to provide the expected evidence or the expected testimony, the court may presume that the litigant avoided the evidence or testimony because such was unfavourable.
Note: Please contact KLP Paralegal Services by phone at: (416) 570-6378 to discuss any specific questions that you may have.
The Law
The adverse inference presumption is based upon the expectation that if a party has control over evidence, the party would present the evidence unless the evidence was unfavourable to the party. The principle was well explained within the case of Tiwari v. Chevalier, 2022 ONSC 3071, as well as the case of Lane v. Kock, 2015 ONSC 1972, wherein each it was respectively said:
[28] Adverse inferences may be drawn from a party’s failure to produce relevant documents they were required to produce or should have produced. (Sarzynick v. Skwarchuk, 2021 BCSC 443, at para. 190.)
[3] The effect of the failure of a party to testify or to call a material witness or other evidence, is summarized as follows in Sydney N. Lederman, Alan W. Bryant & Michelle K. Fuerst, The Law of Evidence in Canada, 4th ed. (Markham: LexisNexis Canada, 2014) at p. 386:
In civil cases, an unfavourable inference can be drawn when, in the absence of an explanation, a party litigant does not testify, or fails to provide affidavit evidence on an application, or fails to call a witness who would have knowledge of the facts and would be assumed to be willing to assist that party. In the same vein, an adverse inference may be drawn against a party who does not call a material witness over whom he or she has exclusive control and does not explain it away. Such failure amounts to an implied admission that the evidence of the absent witness would be contrary to the party's case, or at least would not support it.
The choice to apply an adverse inference is discretion as was explained within the Court of Appeal case of Parris v. Laidley, 2012 ONCA 755, wherein it was said:
[2] Drawing adverse inferences from failure to produce evidence is discretionary. The inference should not be drawn unless it is warranted in all the circumstances. What is required is a case-specific inquiry into the circumstances including, but not only, whether there was a legitimate explanation for failing to call the witness, whether the witness was within the exclusive control of the party against whom the adverse inference is sought to be drawn, or equally available to both parties, and whether the witness has key evidence to provide or is the best person to provide the evidence in issue.
Summary Comment
The adverse inference principle is akin to the common saying of, if you got it, then flaunt it; and is based on the expectation that if a litigant fails to flaunt evidence, the reason for failing to do so is, presumedly, because the evidence is unhelpful, and more likely harmful, to the case of the litigant.
NOTE: A significant number of inquiries regarding “lawyers near me” or “best lawyer in” frequently signify a demand for prompt and effective legal aid rather than a specific professional designation. In Ontario, licensed paralegals are governed by the same Law Society that regulates lawyers and are permitted to represent clients in certain litigation matters. Skills in advocacy, legal assessment, and procedural proficiency are essential to that role. KLP Paralegal Services provides legal representation within its licensed parameters, focusing on strategic positioning, evidentiary preparation, and compelling advocacy aimed at securing swift and favourable outcomes for clients.
