Témoins peu recommandables et témoins Vetrovec

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Principes généraux

A "Vetrovec warning" refers to the special consideration required when considering the reliability of evidence from disreputable or unsavoury witnesses.

A jury must be given a "clear and sharp warning" with respect to the testimony of disreputable or unsavoury witnesses. This is known as a "Vetrovec" warning. This requires that:

1. the evidence of certain witnesses is identified as requiring special scrutiny;
2. the characteristics of the witness that bring his or her evidence into serious question are identified;
3. the jury is cautioned that although it is entitled to act on the unconfirmed evidence of such a witness, it is dangerous to do so; and
4. the jury is cautioned to look for other independent evidence which tends to confirm material parts of the evidence of the witness with respect to whom the warning has been given.

The Vetrovec rules of cautioning juries do not apply to witnesses called by the defence.

Standard of Appellate Review

The question of whether to give the warning and the content of the warning are discretionary decisions of the trial judges and "are accorded substantial deference on appellate review."

Applicable Witnesses

The warning should be applied for the testimony of accomplices and "disreputable witness of demonstrated moral lack" such as "a witness with a record of perjury."

The determination will depend on the circumstances of each witness. There must be an objective basis to suspect the witness's credibility. Factors that can be considered include:

• involvement of criminal activities,
• a motive to lie by reason of connection to the crime or to the authorities,
• unexplained delay in coming forward with the story,
• providing different accounts on other occasions,
• lies told under oath

It not relevant whether the judge finds the witness trustworthy but "whether there are factors which experience teaches that the witness’s story be approached with caution."

The judge must also take into account "the importance of the witness to the Crown's case." A less important witness will not invoke a vetrovec warning, but an essential witness will require the warning.

A drug addiction at the time of the offence does not warrant a witness to be subject to a vetrovec warning.

The warning is often going to be appropriate where a co-accused incriminates an accused is his testimony.

Factors to Consider

Witness characteristics (or "Vetrovec markers") that may require special scrutiny include:

1. Did the witness have any motive to lie or mislead the court?
2. Did the witness receive benefits for cooperation such that there is a risk he is lying to the court?
3. Did the witness have a long criminal history?
4. Did the witness have a history of lying to or manipulating the police?
5. Was the witness an accomplice with knowledge of the circumstances such that it would be easy to falsely implicate the accused?
6. Did the witness have access to disclosure or other information that may explain his evidence or how it was given?
7. Did the witness minimize his own wrongdoing?
8. Did the witness exhibit selective memory?
9. Did important evidence emerge only after the witness exhausted his memory or after prodding by police?
10. Did new information emerge for the first time at trial despite many previous statements?
11. Was the witness evasive?
12. Was the witness testimony inconsistent with external evidence, particularly objective evidence that has been accepted?
13. Did the witness provide prior inconsistent statements?
14. Was the witness internally consistent: did the witness evidence change in testifying?
15. Upon the application of common sense, is the witness evidence impossible, improbable or unlikely?

Exculpatory Crown Witnesses or Defence Witnesses

The warning is only applicable where the witness gives inculpatory evidence.

If a warning is given to exculpatory evidence it may risk reversing the burden of proof.

Necessary Elements Before Making Caution

There are three necessary elements for a caution to be required:

1. when the witness incriminates the accused. Without incrimination, no warning is needed;
2. sufficient reason to doubt the credibility of the witness; and
3. sufficient importance of the witnesses testimony.

Confirmatory and Corroborative Evidence

A trier-of-fact must look for independent confirmatory evidence before accepting evidence from an unsavoury witness. "Confirmatory evidence" should be independent and reliable. It does not need to confirm every aspect of the case but rather should corroborate significant parts of the evidence. It is not necessary that the confirming evidence always be independent. It need only needs to be "capable of restoring the trial judge's faith in the relevant aspects" of the witnesses account. It cannot be evidence that is equally consistent with truth than with falsity of the witness.

There is no strict legal requirement for corroboration. It so only necessary that there be a warning.

Where the corroborative witness has been "tainted by a "connection" to the Vetrovec witness. Their evidence cannot be used as corroboration.

Evidence of the unsavory witness pleading guilty to the same offence as the accused can be confirmatory evidence.

Discretionary Decision

The extent to which the evidence is properly corroborated is a matter of judicial discretion and judges are afforded considerable latitude in this regard.

Vetrovec Warning

In a jury trial where a Vetrovec witness has testified, the instructions to the jury must include a "Vetrovec warning".

In a judge-alone trial, the need to expressly self-instruct is at the discretion of the judge. The centrality of the particular witness does not have the effect of making the instruction mandatory.

One view suggests that a caution must be given even when the "testimonial blemishes" are apparent to the triers.

The purpose of confirmatory evidence is to "restore in the trier's mind confidence in the reliability of the witness's evidence after recognizing the problem."

Factors the court should consider when counsel requests a Vetrovec warning:

1. The Vetrovec warning is designed to alert the trier of fact to the need for special attention when assessing the credibility of certain unsavoury witnesses.
2. It is a clear and sharp warning to alert the trier of fact to the risk of adopting, without more, the evidence of an unsavoury witness
3. The warning assigns unsavoury witnesses a special status, namely, it sets them apart from other witnesses and encourages an assessment of their credibility bearing in mind the unique reliability concerns they bring to a trial.
4. The purpose of the Vetrovec warning is to alert the trier of fact that there is a special need for caution in approaching the evidence of certain witnesses whose evidence plays an important role in the proof of the accused’s guilt.
5. There are four stages that ought to be considered when approaching the testimony of a potentially unsavoury witness, namely:
   1. the evidence of certain witnesses is identified as requiring special scrutiny;
   2. the characteristics of the witness that bring his or her evidence into serious question are identified;
   3. the trier of fact is cautioned that although it is entitled to act on the unconfirmed evidence of such a witness, it is dangerous to do so;
   4. the trier of fact is cautioned to look for other independent evidence which tends to confirm material parts of the evidence of the witness with respect to whom the warning has been given.
6. There are no hard and fast rules in determining whether a witness is deserving of a Vetrovec warning. However, as the importance of the witness to central issues at trial increases, and the credibility concerns rise, so does the need for a caution.

See also: R c Tymiak, 2009 BCCA 98 (CanLII), 267 BCAC 120, par Frankel JA (3:0), aux paras 30 à 32; Discretion to Give Warning The judge had wide discretion on whether to give a Vetrovec warning.

Where the witness provides "mixed" evidence that gives a significant amount of evidence that is helpful for the defence as well as the crown, the judge has the discretion whether the still invoke the warning.

Failure of defence counsel to request a Vetrovec warning or object to the lack of jury instruction may remove any ground of appeal on its absence. In fact it may be a tactical decision to avoid instructions that may involve listing all corroborative evidence.

Failure of Counsel to Request a Warning

Where the accused failed to request a warning resulting in no warning being given is not a situation where a "non-direction amounting to a misdirection."

Timing of Warning

It is generally inappropriate to give a vetrovec warning mid-trial. It should only be given at the final instructions.

Form of Caution

Given the wide discretion of the judge in giving a Vetrovec caution, the judge also has wide discretion on the form of the warning. A judge can give:

1. no opinion or caution to jurors about a witness’s testimony,
2. a full Vetrovec warning, a clear and sharp caution against acting on the suspect witness’s evidence without more,
3. an “equivalent warning” to that required by Vetrovec, or
4. a “lesser instruction” alerting jurors to features of the witness’s evidence or background to take into account in assessing the worth of the witness’s evidence.

It is suggested that a vetrvec warning will include the following advisories to the triers of fact:

1. the evidence of the witness is identified as requiring special scrutiny;
2. the characteristics of the witness that bring his or her evidence into serious question are identified;
3. the jury is cautioned that although it is entitled to act on the unconfirmed evidence of such a witness, it would be dangerous to do so; and
4. the jury is instructed to look for other independent evidence which tends to confirm material parts of the evidence of the witness for whom the warning is being given.

Additional Jury Instruction Consideration

Where there are inconsistencies between the testimony of a Vetrovec witness and a prior statement, the judge must draw the jury's attention to the need to review them.

"Cut-Throat" Defence

When a co-accused implicates the other accused while asserting non-involvement, the judge should be concerned that "he may be falsely implicating his co-accused to escape liability." A jury should usually be advised that such evidence must be "assessed with caution." The jury should also be told that no concern should be applied against the other accused.

This is sometimes referred to as an "Oliver caution."