DRAWING THE LINE BETWEEN LAY AND EXPERT OPINION EVIDENCE.

AuthorChin, Jason M.
PositionCanada

Tins article examines the vanishingly thin line between lay and expert opinion evidence in Canada. In Parts I and II, we set the stakes--the dangers involved in expanding the scope of admissible opinion evidence. Canadian trial courts have been warned by peak scientific bodies and public commissions like the Goudge Inquiry about the dangers of attorning to persuasive expert witnesses. Thus, expert evidence faces new hurdles, both substantively and procedurally. This scrutiny has inspired parties to seek refuge in the more flexible and discretionary lay opinion evidence rules. But newfound vigilance to expert opinion is invalidated if the same evidence can be admitted as lay opinion. Parts III and IV illustrate these problems as we examine three cases in which authoritative lay witnesses opined on topics requiring specialized training and expertise. Three hazards are readily apparent from this analysis: (1) the lay witnesses opined on matters in which there are established methodologies to control for unconscious bias, but did not follow these methodologies; (2) the lay witnesses--police officers--though authority figures, were not qualified experts in the area they were opining on, and; (3) the lay opinion jurisprudence has failed to meaningfully distinguish between lay and expert opinion. In Part V, we seek to fill this void by proposing a new analytic approach--Lay Opinion 2.0--which draws on both the practical and epistemological distinction between lay and expert opinion to provide an efficient and fair test for the admission of lay opinion evidence.

Cet article examine la difference de plus en plus mince entre la preuve d'un temoin ordinaire et la preuve d'un temoin expert au Canada. Dans les parties I et II, nous presentons les enjeux au centre de cet article. Les tribunaux canadiens de premiere instance ont ete avertis par des organismes scientifiques de pointe et par des commissions publiques comme la commission Goudge des dangers d'acquiescer a des temoignages d'experts convaincants. Ainsi, la preuve d'expert est confrontee a de nouveaux obstacles, tant sur le plan materiel que procedural. Cette attention particuliere a encourage les parties a se tourner vers les regles qui s'appliquent aux temoins ordinaires, qui sont plus flexibles et discretionnaires. Pourtant, la vigilance recemment decouverte pour les opinions d'experts se voit invalidee si la meme preuve peut etre admise en tant que preuve ordinaire. Les parties III et IV illustrent ces problemes, examinant trois cas dans lesquels des temoins ordinaires faisant autorite dans leur domaine ont donne un avis sur des sujets exigeant une formation et une expertise specialisees. Trois risques ressortent spontanement de cette analyse: (1) les temoins ordinaires ont donne leur opinion sur des questions pour lesquelles il existe des methodologies de controle des biais inconscients, mais ils n'ont pas suivi ces methodologies; (2) les temoins ordinaires--des policiers--bien que representant des figures d'autorite, n'ont pas ete qualifies d'experts dans le domaine dans lequel ils ont donne leur avis; et (3) la jurisprudence portant sur la preuve ordinaire n'a pas distingue de maniere claire l'opinion des experts et des temoins ordinaires. Dans la partie V, nous cherchons a combler ce vide en proposant une nouvelle approche analytique--la preuve testimoniale ordinaire 2.0--qui s'appuie sur la distinction a la fois pratique et epistemologique entre le temoignage du temoin ordinaire et celui de l'expert, afin de fournir un critere efficace et equitable pour l'admission de la preuve ordinaire.

Introduction I. The Rising Bar for Expert Opinion II. The Lay Opinion Rule and its Lost Moorings A. A Crime Scene Cleanup in R. v. Ilina B. Footsteps in die Snow in R. v. Lee C. The Lay Forensic Accountant in R. v. Colpitts III. The Hazards of Lay Experts A. Mediodology versus Qualia B. Specious Nexus between Authority and Evidence C. Failures in the I-ay Opinion Jurisprudence IV. Lay Opinion Evidence, Next Generation A. Lay Opinion 2.0 1. Step 1: Identification 2. Step 2: Characterization 3. Step 3: Exclusion of Secondhand Evidence 4. Step 4: The Lay Opinion Gatekeeper Conclusion Introduction

Evidence in the form of opinion, any opinion, is presumptively inadmissible. Expert opinion evidence is subject to increasingly stringent substantive and procedural requirements prior to its admission into court. This heightened gatekeeping of expert opinion has motivated parties to sidestep those requirements and admit evidence as lay opinion, which is subject to a more flexible and discretionary test. As a result, it has never been more important for courts to draw a coherent distinction between lay and expert opinion. This has not been the case with lay witnesses--often police officers--now opining on traditionally expert topics in a manner exceeding their own personal observations and qualifications. Worse still, as police officers, they are cloaked in the same raiment of authority that makes expert evidence so dangerous. We believe this is a serious problem, and one that has largely flown under the radar in Canada. (1)

Trial judges gatekeep expert evidence because of the risk that the trier of fact will uncritically accept an opinion "cloaked with an aura of expertise." (2) This gatekeeping function has the further benefit of avoiding lengthy battles between experts when that expertise is not relevant, necessary, reliable, or qualified to begin with. This is crucially important to the criminally accused parties who are frequently underfunded in comparison to the Crown. (3)

The exception for lay opinion did not evolve to undermine these expert rules, but rather as a concession to practicality--a recognition that some experiences, like eyewitness identifications and judgments of speed, are difficult to enunciate without resorting to opinion. Evidence now admitted as lay opinion regularly goes far beyond these humble beginnings, encompassing conclusory opinions about police investigations, forensic gait analysis, and complex accounting opinions. This approach can result in manifestly unjust outcomes. For instance, under the lay rule, an investigating police officer may give lay opinion that a complex series of footsteps he viewed in the snow indicated there was a chase, and that the accused cut off the complainant. (4) The accused, wishing to rebut that evidence, cannot in turn call a lay witness because the lay opinion rule, at least notionally, requires personal observation of the facts. Thus, the accused has little choice but to call an expert, who is likely expensive and may not pass the more stringent test for expert opinion.

In what follows, we will first review the expert and lay opinion rules to establish the stakes at the center of this article: why the distinction between lay and expert opinion evidence is so important. The expert opinion rules, in response to several notorious miscarriages of justice, have become in substance and in procedure increasingly demanding over the past two decades. It is therefore important that courts correctly distinguish between lay and expert opinions, lest parties undermine expert opinion doctrine by admitting their evidence as lay opinion. We then highlight three decisions emblematic of the permissive approach to lay testimony.

We go on to detail three hazards that emerge from our review of the case law. First, lay opinion evidence is unmoored from its original conception as a succinct summary of qualia. Rather, lay witnesses now opine on areas where methodologies exist to control for unconscious biases. For example, humans are excellent pattern seekers and regularly identify illusory patterns in large sets of data. This is especially true when people have some preconceived notion or bias about what they should find, as investigating police officers often do. Yet, because the lay opinion rule is more permissive, lay witnesses need not follow methodologies recently prescribed by peak scientific bodies or generally meet the more stringent reliability requirements imposed on expert opinions. (5)

The second hazard amplifies the first: the lay witnesses providing ipse dixit are, by all appearances, not lay people. Rather, they are often police officers with some superficial investigative experience in the areas on which they are opining--for instance, an expert in police dog behaviour opining on the significance of a pattern of shoe-prints in the snow. These quasi-experts can be expected to hold sway over the trier of fact, but they are not required to prove that they are properly qualified or that their methods are reliable.

Third, courts have faded to adopt a coherent jurisprudential approach to lay opinion across Canada. The principles from the leading Supreme Court case, R. v. Graat, are inconsistently applied and sometimes ignored altogether. (6) Several decisions, even when given a charitable reading, are irreconcilable. The courts' inconsistent approach creates confusion and injustice.

Taking these three hazards into account, we offer an improved approach to lay opinion evidence. As a guiding principle, we suggest a return to Graat, which remains the leading Supreme Court case on lay opinion which, as we demonstrate, has been widely disregarded. Our proposed approach provides a more structured analysis based on Graat's principles, which we believe will assist trial judges in applying the proper scrutiny to lay opinion.

  1. The Rising Bar for Expert Opinion

    In this part, we will review the preconditions for admissibility of expert evidence: what the party tendering the expert must prove before the expert evidence is admitted. We will also discuss the current trend in expert evidence law, whereby the doctrine has grown increasingly restrictive.

    Expert evidence is subject to a relatively onerous test prior to its admission. The party seeking to admit the evidence must establish its admissibility by satisfying four...

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