8. Expert/opinion evidence
An expert is a person possessed of special skill and knowledge acquired through study or experience that entitles them to speak authoritatively concerning their area of expertise. A panel may permit an expert to give oral or written opinion evidence on subject matter that is outside the panel's knowledge and experienceFootnote 173 (e.g., medicine, psychology, country conditions,Footnote 174 document authentication,Footnote 175 anthropology,Footnote 176 foreign lawFootnote 177). Before admitting opinion evidence from a proposed expert witness, a panel should consider whether the witness is in a better position than the panel to form an opinion or draw inferences from the facts.Footnote 178
A panel is not bound to accept and give full weight to expert opinion; to the contrary, the Federal Court has warned against giving such opinions “exalted status” in administrative proceedings simply because they are prepared by experts.Footnote 179 Instead, expert opinions should be weighed much like any other evidence.Footnote 180 A panel's assignment of weight to an expert opinion will generally attract deference on judicial review.Footnote 181
Various factors that may affect the weight assigned to expert opinions are discussed below.
8.1 Qualifications and expertise
As a general rule in the law of evidence, witnesses appearing before a court “are to testify as to the facts which they perceived, not as to the inferences—that is, the opinions—that they drew from them.” Ready-formed inferences generally are not helpful to the trier of fact, and may be misleading.Footnote 182 However, there are exceptions to this general rule, including the admissibility of opinion evidence from an expert witness who has been formally qualified (i.e. shown to have acquired special or peculiar knowledge through study or experience in respect of the matters on which they undertake to testify).Footnote 183
None of the four Divisions of the IRB is bound by any legal or technical rules of evidence,Footnote 184 and expert witnesses do not need to be formally qualified as such in order to give opinion evidence in IRB proceedings. However, each Division has a rule regarding witnesses,Footnote 185 and despite some differences in the wording of these rules, they all require disclosure of an expert witness's qualifications and a signed summary of the evidence the expert witness will provide.
An expert witness appearing before the IRB should only be permitted to give opinion evidence on subject matter that is within their particular area of expertise. At the outset, the panel should determine the area of expertise asserted and compare it with the expert's qualifications, including their education, professional designations, and any other relevant experience. Any challenge to the qualifications of an expert witness should be made as soon as possible.Footnote 186 When a witness's expertise is not in doubt, the panel should take particular care in explaining why it has assigned limited or no weight to their evidence, especially if the evidence tends to support a party's position.Footnote 187
Generally, a panel may assign little or no weight to opinion evidence that exceeds the scope of the witness's expertise, provided it properly justifies its decision.Footnote 188 In
Lopez Estrada,Footnote 189 the panel found a proposed witness was not an expert on country conditions in Guatemala, as she did not live and work in that country during the relevant time period. The Federal Court upheld the decision and found the proposed witness did not have specialized knowledge and experience going beyond that of the panel.
Sokhi,Footnote 190 the Federal Court found the RPD was correct to question the quality of a psychological report because it was authored by an orientation specialist who was not a registered psychologist. Similarly, in
Aleman,Footnote 191 the court declined to interfere with the Convention Refugee Determination Division's decision to assign no weight to an expert report that partly attributed the applicant's misrepresentations to post-traumatic stress syndrome. The expert had no professional training, extensive experience, or publications on the subject.
Enam,Footnote 192 the Federal Court held it was unreasonable for the RAD to give little weight to a clinical social worker's report on the applicant's psychological state. Although the RAD reasonably found the expert had exceeded her statutory authority by communicating a diagnosis, it erred in failing to properly consider that clinical social workers belong to a regulated profession and are authorized to treat certain serious psychological disorders.
It may be an error to discount an expert's opinion on a matter that is within their expertise because of inadequate answers relating to matters outside their expertise. In
Wang,Footnote 193 the ID had rejected evidence from the applicant's expert, in part because his answers regarding Chinese passport law were inconsistent with documentary evidence that the applicant's previous counsel adduced. The Federal Court found this was unreasonable, as the witness had been offered as an expert on Chinese arrest and bail procedures. The expert did not purport to be qualified to give evidence on passport laws, and any evidence he gave on the subject would be either inadmissible or irrelevant.
While a witness's speculation will generally be of little or no value to a panel,Footnote 194 an expert witness may be qualified to make certain predictions regarding future events or outcomes. In
Ampong,Footnote 195 a PRRA officer had unreasonably found a medical expert's opinion to be of limited probative value because it was “somewhat speculative in nature”. Justice Russell wrote “it is not speculative for a qualified medical practitioner to conclude that, if the Applicant does not receive treatment that meets his needs, the likely result will be serious illness and death.”
8.2 Assessing experts' conclusions
An expert witness's purpose is to address subject matter that is beyond a panel's knowledge and experience. Accordingly, a panel will not usually be in a position to directly dispute inferences that fall within the scope of the expert's demonstrated expertise. For example, in
Trembliuk,Footnote 196 Justice Gibson of the Federal Court wrote:
While it was open to the RPD to determine the weight, if any, to be given to the assessment provided by the psychologist, it was not open to the RPD to reject the psychologist's diagnosis. While the RPD is undoubtedly a specialized tribunal […], it is certainly not an expert tribunal in the area of psychological assessment.
Lozano,Footnote 197 the applicant had submitted to the RPD a psychiatrist's report that diagnosed the applicant with bipolar disorder. The Federal Court found that the RPD demonstrated a degree of skepticism that was entirely unwarranted in the circumstances by stating it was “possible that the claimant is bipolar [emphasis added].”
That is not to say that expert evidence must be given full weight in all circumstances. The Supreme Court of Canada has warned of the potential danger of inappropriately deferring to an expert's opinion rather than carefully evaluating it.Footnote 198 Instead, when assessing expert evidence, a panel may examine various collateral issues (such as those discussed in this chapter) to determine whether the expert evidence has been sufficiently proven to be credible.Footnote 199
Czesak,Footnote 200 Justice Annis of the Federal Court cautioned decision makers against undue reliance upon expert reports that have not undergone the “rigorous validation process” typically seen in court proceedings, which may include an opposing party's rebuttal report and cross-examination of the expert, among other things. Justice Annis wrote (at para. 40):
… [W]hat the court's experience with forensic experts does suggest in relation to these reports being proffered before administrative tribunals where there exists no defined procedure to allow for their validation, is that caution should be exercised in accepting them at face value, particularly when they propose to settle important issues to be decided by the tribunal. In my view therefore, unless there is some means to corroborate either the neutrality or lack of self interest of the expert in relation to the litigation process, they generally should be accorded little weight.
IRB proceedings do not typically include a process for validating expert reports that is as extensive as those seen in adversarial court proceedings. Other judges on the Federal Court have reiterated Justice Annis's cautions about undue reliance upon expert reports in the context of judicial reviews of IRB proceedings,Footnote 201 although the suggestion that such reports should generally be accorded little weight has not been widely adopted.Footnote 202
The concerns about experts' neutrality and lack of self-interest raised in
Czesak are also reflected in various Federal Court decisions involving expert evidence that has crossed the line between objective opinion and advocacy. The court has held that such evidence lacks probative value and may be given little or no weight.
For example, in
Molefe,Footnote 203 a psychologist's report crossed the line into advocacy by asserting a refugee claimant's condition “can improve with appropriate care and guaranteed freedom from her threat of removal”, “[i]f refused permission to remain in Canada, her condition will deteriorate”, and “it will be impossible for [her] to feel safe anywhere” in her country of nationality. The court held the report lacked reliability.
Egbesola,Footnote 204 the court considered a psychologist's report that contained similar statements, and held that such statements had “virtually no probative value.”
Moffat,Footnote 205 the court agreed with the RPD's conclusion that a clinical psychologist's report should be given little weight. In extensive reasons, Justice Annis expressed concerns about the author's independence and impartiality. Among other issues, he cited what he found to be examples of the expert advocating on behalf of the applicant. He wrote:
These are not opinions intended to
assist the RPD to better understand the influence of mental disorders in some form that are
relevant to issues before the RPD. Rather, they are directives, and in many cases categorical, with the view to persuading the RPD to implement an obvious strategy in support of her lawyer's presentation of its case before the RPD. [Emphasis in original.]
Enam,Footnote 206 the court held the RAD's finding that a clinical social worker's opinion had crossed the line into advocacy was unreasonable. The impugned portion of the opinion said the applicant's “fear is so great and the certainty of his capture, and torture and eventual death is so strong that it is my professional opinion that there is a real threat of [the applicant] committing suicide if he is forced to return to Afghanistan.” Although the court found this statement did not constitute advocacy, it declined to give this aspect of the report any weight as the author was not an expert on Afghan country conditions.
Even if some of an expert's statements seem to cross the line into advocacy, it may not be appropriate to discount their entire opinion. Generally, a panel may give the impugned statements little or no weight, but should consider whether the remaining evidence has probative value.Footnote 207 Because the panel's determination of whether expert evidence crosses the line into advocacy is a matter of weighing evidence and assessing its bearing on the facts, it should be afforded deference on judicial review.Footnote 208
8.4 Expert evidence relating to credibility
Determining whether witnesses are providing accurate testimony is one of a decision-maker's central functions. Experts should not generally opine as to whether a witness is or is not credible.Footnote 209
However, expert evidence may tend to corroborate a party's allegations regarding past events. For example, a medical expert may properly opine that, based on their objective assessment, a claimant for refugee protection has scars of injuries consistent with their allegations.Footnote 210 Such an opinion may still be valid evidence despite its circumstantial nature; in other words, it may have probative value even though the author did not observe the cause of the injuries first-hand.Footnote 211
Expert opinion that is based entirely on a party's account of the relevant facts may be less reliable, and thus deserving of less weight, particularly where there are reasons for a panel to question the party's credibility. In
Danailov,Footnote 212 Justice Reed of the Federal Court – Trial Division wrote:
With respect to the assessment of the doctor's evidence, to find that that opinion evidence is only as valid as the truth of the facts on which it is based, is always a valid way of evaluating opinion evidence. If the panel does not believe the underlying facts it is entirely open to it to assess the opinion evidence as it did.
Saha,Footnote 213 the Federal Court stated the RPD may “discount psychological evidence when the doctor merely regurgitates what the patient says are the reasons for his stress and then reaches a medical conclusion that the patient suffers stress because of those reasons.” Before rejecting expert opinion on the basis that the underlying facts are not credible, a panel should ensure the opinion was not supported by information independent of the witness's credibility, such as the expert's first-hand observations or the results of objective tests.Footnote 214 For example, in
Joseph,Footnote 215 the Federal Court explained that “a health expert's report based on a current examination of a patient's symptoms must be given more weight than a report based exclusively on a patient's own account of what happened.”
Furthermore, panels should have regard to the purpose(s) for which expert evidence was adduced. For example, expert evidence regarding a person's psychological condition may be intended to explain potential problems with the quality of that person's testimony, rather than to corroborate their account of the events that purportedly caused the condition. Failure to recognize such a distinction and assess how the report impacts the assessment of credibility may lead to a decision being overturned on judicial review. For example, in
Feleke,Footnote 216 the Federal Court stated:
 In considering mental health assessments when evaluating the Applicant's credibility, there are two reasons why the assessment may aid an Applicant. First, it may serve as corroborative evidence of an Applicant's story or second, it may provide an explanation for the inconsistencies in the Applicant's evidence. Jurisprudence of this court has supported the notion that mental health assessments may be tendered for either purpose.
 I agree with the Applicant that the RPD did not consider the impact of the psychological report on the discrepancies of Applicant's evidence, all the while acknowledging the Applicant's difficulties during her testimony…
 The medical assessment, which the RPD accepted, stated that the Applicant suffered from “cognitive difficulties, avoidance behaviours, generalized anxiety symptoms”, all of which could have provided an explanation for the Applicant's behaviour. The RPD, in finding a decision either way, with regards to credibility, had an obligation to explain how the diagnosis impacts the RPD's assessment of any discrepancies.
However, where problems with testimony (e.g., inconsistencies, omissions) are found to be unrelated to the person's condition, expert evidence regarding that condition may be given little or no weight.Footnote 217 In
Zararsiz,Footnote 218 an expert opined that the applicant met the diagnostic criteria for post-traumatic stress disorder. The RAD reasonably found that the expert report did not explain the deficiencies in the applicant's evidence, which arose not from his inability to recall details, but from significant inconsistencies between his statements at the port of entry and various iterations of his Basis of Claim narrative.
8.5 Factors to consider relating to the weight of expert evidence
The following is a non-exhaustive list of factors that may be considered when assessing the weight to be given to expert evidence:
- whether the evidence is within the expert's area of expertise;
- the manner in which the expertise was acquired;
- whether the expert's opinion was formed with full knowledge of the relevant facts;
- the facts and assumptions the expert relied upon;
- whether the facts the expert relied upon have been established;
- the quality of source material the expert relied upon;
- the reliability of the expert's methods (e.g., the nature of any tests applied, whether the methods were culturally sensitive);
- whether the expert has relied upon hearsay in forming their opinion and the reliability of that hearsay;Footnote 219
- whether any hearsay the expert relied upon is of a nature generally relied upon by other experts in the field;
- whether there is evidence that other experts in the field hold different opinions on the subject matter;
- any radical views the expert holds;
- the expert's independence and impartiality;
- whether the expert has examined the party or simply referred to existing records;
- whether the expert has provided sufficient justification for their conclusions;
- when the opinion was prepared in relation to the timing of the proceeding; and
- the purpose for which the expert evidence was submitted (e.g., corroborating allegations, explaining foreseeable problems with the quality of testimony).