A trial judge should draw an adverse inference from the failure of a party to call a witness only with the greatest of caution.

See R. v. Ellis, 2013 ONCA 9 (CanLII), at para 49.

An adverse inference can only be drawn where there is no plausible reason for nonproduction, in other words, where it would be natural for the party to produce the evidence if the facts exposable by the witness had been favourable.

See R. v. Ellis, 2013 ONCA 9 (CanLII), at para. 48.

The only adverse inference that the trier of fact may drawn is that if the witness were called his/her testimony would be unfavourable, eg., would bear adversely on the credibility of the accused. An inference of guilt is not permissible.   

R. v. Koffman (1985), 20 C.C.C. (3d) 232, 10 O.A.C. 29, per Martin JA.

Comment on the Failure to Produce a Witness

It is rarely permissible for the trial judge to comment on the failure to call a witness.

Even where a comment on the failure to call a witness is appropriate, the failure to call a witness should not be given undue prominence and a comment should only be made where the witness is of some importance in the case.

R. v. Koffman (1985), 20 C.C.C. (3d) 232, 10 O.A.C. 29, per Martin JA.

The judge or counsel for the prosecution are prohibited from commenting on the failure of the accused (or the husband or wife of the accused) to testify.

Section 4(6) of the Canada Evidence Act.

Where neither the Crown nor the accused might wish to call, the jury may be so advised but the jury should not be told that if they concluded the defence should have called a witness, they could draw an adverse inference against the accused.

Where the Defence Fails to Call a Witness

To draw an adverse inference against an accused in a criminal trial risks imposing a burden of adducing evidence on the accused, thereby shifting the onus of proof.

R. v. Lapensee, 2009 ONCA 646 (CanLII), at para. 45.

There is no obligation on the defence to call a particular witness and there may be a perfectly valid reason for not calling the witness.  The trial judge should instruct the jury accordingly when comment has been made regarding the failure to call a witness.

R. v. Koffman (1985), 20 C.C.C. (3d) 232, 10 O.A.C. 29, per Martin JA.

 Where the Crown Fails to Call a Witness

As a matter of general principle, Crown counsel is under no obligation to call a witness whom the Crown considers is unnecessary to the Crown’s case.

It is all the more so where Crown counsel does not know of the existence or identity of the witness, or considers the evidence of the witness unworthy of belief.

Jolivet, at para. 29.

Even where the Crown does not call a relevant witness, in most cases defence counsel will have the ability to call that same witness. [FN1]

In civil proceedings, an adverse inference following from a failure to call a witness may not be drawn unless, among other things [FN2], the party that failed to call the witness alone had the ability to bring the witness before the court.

            Buck v Morris, 2013 ONSC 7596 (CanLII).

The “adverse inference” principle is rooted in ordinary logic and experience: R. v. Ellis, at para. 48. In my opinion, the ability of the defence to call the witness the Crown has not called is relevant to whether or not an adverse inference should be drawn against the Crown.

[FN1] If the defence has any concerns with respect to the evidence the witnesses might present and whether they could be adverse to the accused, an application to have the witness declared adverse should be made so that his/her evidence can be the subject matter of cross-examination by the defence.

[FN2]: Buck v Morris, 2013 ONSC 7596 (CanLII):  a)The party has not explained the failure to call an important witness, b) the evidence of that witness has not been provided from other sources, c) a prima facie case has been established by the opposing party that the party failing to call a witness must disprove or risk losing the case, and d) that party alone could bring the witness before the court.

Stuart O’Connell, O’Connell Law Group (all rights reserved to author).