Secondary Materiality and Your Own Witness

• Author: David M. Paciocco/Lee Stuesser
• Pages: 485-518

485

CHA PTER 11

SECONDARY

MATERIALITY AND

YOUR OWN WITNESS

1. THE BAR ON BOLSTERING THE

CREDIBILITY OF YOUR OWN WITNESS

As a general rule, a party m ay not ask questions or present e vi-

dence solely to bolster the credibility of his own witness.

Although it may be of assistance to hear te stimony about t he value of

the evidence that has been led in a case, there is concern that to allow

this would take an undue amount of time and cre ate di stracting side

issues. Until their credibility h as been made an issue by the opposing

party, witnesses are a ssumed to be trust worthy and of good character.1

As a general rule, therefore, a party c annot in itiate ev idence solely to

establish that his witnesse s a re cred ible. Evidence must be about the

primarily materi al issues i n the case, not about other evidence in the

case. In R. v. Siu this rule was contravened where a police off‌icer stated

that he believed the key Crown witness.2 The rule was further breached

when the off‌icer te stif‌ied that his belief was based in part on the offer

of the Crown witness to take a polygraph test. Where a party leads

inadmissible evidence to support the credibilit y of one of its witnesses

1 R. v. Giraldi (1975), 28 C.C.C. (2d) 248 (B.C.C.A.), leave to appeal to S.C.C.

refused (1975), 28 C.C.C. (2d) 248n (S.C.C.).

2 (1998), 124 C.C.C. (3d) 301 (B.C.C.A.). And see R. v. Austin (2006), 214 C.C.C.

(3d) 38 at 47 (Ont. C.A.).

THE LAW OF EVIDENCE486

in a jury trial, the tri al judge should immediately direct the jury to

disregard the evidence.3

At the same ti me, it i s perm issible and indeed customary to intro-

duce a witness to the court. It is common to see witnesses provide their

age and describe their family and employment status and their connec-

tion to t he case. Frequently, counsel will attempt to introduce his wit-

ne sse s i n a w ay t hat wi ll e nh anc e th e wi tne ss ’s cr edi bil it y. It i s a que sti on

of degree when the line is crossed between permissible introduction and

impermissible “bolsteri ng.” In R. v. Clarke, for example, that line was

crossed when a police informant testif‌ied that he was allowed to leave

the prison for street vi sits, he was studying the Bible, he attended Alco-

holics Anonymous, and he had reformed his cr iminal ways.4

2. GOOD CHA R ACTER EV IDENCE:

THE ACCUSED AS A WITNESS

By way of exception, as an indulgence to the accused in a criminal case,

the accused can prove his good character in a var iety of ways. Such

evidence is considered relevant both to the primarily material issue

of whether the accus ed committed t he offence charged and to the sec-

ondarily material issue of the credibility of the accused as a witness.5

The methods for presenting such evidence on the issue of credibility

are identical to those available where the good character evidence is

being offered to ca st doubt on the guilt of t he accused.6 In particular,

the testify ing accused can assert his own honesty, and other witnesses

can be called to testify a s to the reputation of the accused for truthful-

ness and veracity.7 If the accused choose s to put hi s character in issue

in either of these ways, the Crown will be entitled to rebut the claim to

good character by cross-examining the accused or character w itness,

or by calling other witnesses who will testif y to the accused’s bad repu-

tation for trustworthiness or sincerity.

3 R. v. Siu, ibid.

4 (1981), 63 C.C.C. (2d) 224 (Alta. C.A.).

5 R. v. H.(C.W.) (1991), 68 C.C.C. (3d) 146 (B.C.C.A.).

6 See chapter 3, section 13, “Good Character Evidence and Modes of Presentation.”

7 R. v. Clarke (1998), 18 C.R. (5th) 219 (Ont. C.A.).

Secondar y Materiality and Your Own W itness 487

3. SECONDARILY MATER IA L EXPERT

EV IDENCE

A party may call an expert witness to testify about facts relevant to

the credibility of one of his witnesses where those facts are likely to

be beyond the experience of the trier of fact. The rule against oath-

helping prevents the e xpert from going so far as to testify that the

witness is likely to be telling the truth.

In R. v. Kyselka,8 the Ontario Court of Appeal held that it was impermis-

sible for a medical doctor to ex plain that a mentally challenged sexual

assault complainant lacked the imagination and intel ligence to con-

coct the story she had told. The Cour t said this was analogous to the

pre-Norman practice of “oath-helping,” by which a party would call

persons who knew nothing of the event, but who would swear that this

party’s oath was t rue. Similar reasoning was employed by the Supreme

Court of Canada in R. v. Béland9 to reject the admission of the evidence

of a polygraphist who would have testif‌ied that the accused passed a lie

detector test.

Recently, courts h ave taken a more generous view. In some case s,

factors relevant to the credibility of a witnes s are beyond t he ordinar y

experience a nd understanding of lay triers of fact. Without the a ssist-

ance of experts, lay triers of fact are apt to make erroneous assumptions

about credibility. For example, laypersons may not appreciate that chil-

dren can not be expected to notice t ime and place the way t hat adults

do, or that sexually abused chi ldren are prone to fantasize or to retract

their allegations.10 Or they may not appreciate that the professed inabil-

ity to recall can be the result of hysterical amnesia.11 Where common

experience does not prov ide the tools needed to assess t he credibility

of a witness, a party will be entitled to call an expert to provide that in-

formation, even though the testimony of the expert does nothi ng more

than support the credibility of another witnes s.

This practice is not without its limits. The moder n rule against

oath-helping prevents expert witnesses f rom offering t he opinion that

a particular witness i s telling the truth. The ex pert ca n provide back-

ground information relevant to the credibilit y of a witnes s, but not in-

formation directly about the credibility of what a witness is s aying.12

8 (1962), 37 C.R. 391 (Ont. C.A.).

9 (Sub nom. Béland v. R.) (1987), 60 C.R. (3d) 1 (S.C.C.).

10 See, for ex ample, R. v. J.(F.E.) (1990), 74 C.R. (3d) 296 (Ont. C.A.).

11 R. v. Clark (1983), 35 C.R. (2d) 357 (Ont. C.A.).

12 See generall y, chapter 6, section 3.3, “The Rule aga inst Oath-helping.”