Exigences légales relatives à la preuve d'expert qualifiée

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Principes généraux

Un juge de première instance doit déterminer sur un « voir-dire » si l'individu est qualifié d'expert et, dans l'affirmative, quelle sera « la nature et la portée de la preuve d'expert proposée ».[1] Le processus de qualification consiste à délimiter les limites des preuves et le langage utilisé. [2]

Le juge ne peut pas permettre à l'expert de donner un avis sur des questions courantes ou sur des questions sur lesquelles l'expert n'a pas de compétences, de connaissances ou de formation particulières.

La qualification comporte deux phases. Premièrement, la partie requérante « doit établir les conditions minimales d'admissibilité » selon le critère de Mohan.[3] Deuxièmement, le juge doit exercer son pouvoir discrétionnaire en tant que gardien et équilibrer les « risques et avantages potentiels de l'admission de la preuve ».[4]

Objectif

L'objectif principal de la limitation de la preuve d'opinion est d'éviter d'usurper le pouvoir du juge des faits de trancher une affaire et de déléguer le processus de procès en un « procès par expert ».[5]

Il existe un risque qu'un expert insuffisamment qualifié fournisse des preuves qui seront utilisées à mauvais escient et fausseront le processus d'établissement des faits.[6] La situation est encore pire étant donné que l'avocat n'est pas un expert dans le domaine et peut ne pas être en mesure d'évaluer les allégations de manière critique par le biais d'un contre-interrogatoire.[7]

Un objectif secondaire est de garantir que le temps et l’argent ne soient pas gaspillés inutilement.[8]

Obligation continue de la Cour d'évaluer l'admissibilité

Les tribunaux doivent être « vigilants dans la surveillance et l'application de la portée appropriée des preuves d'experts » étant donné l'impact qu'elles ont sur un procès, y compris le risque « d'usurper le rôle du juge des faits ».[9] This supervision must occur "throughout the expert's testimony" and not simply at the voir dire.[10]

  1. ↑ R c Preeper and Doyle, 1888 CanLII 56 (SCC), (1888), 15 SCR 401
  2. ↑ R c Abbey, 2009 ONCA 624 (CanLII), 246 CCC (3d) 301, par Doherty JA
    White Burgess Langille Inman v Abbott and Haliburton Co, 2015 SCC 23 (CanLII), [2015] 2 SCR 182, par Cromwell J, aux paras 22 to 24
    R c AK, 1999 CanLII 3793 (ON CA), 137 CCC (3d) 225, par Charron JA
  3. ↑ Burgess blanc, supra, au para 23
  4. ↑ , ibid., au para 24
  5. ↑ White Burgess, supra, au para 18 ("The point is to preserve trial by judge and jury, not devolve to trial by expert")
  6. ↑ R c Mohan, 1994 CanLII 80 (SCC), [1994] 2 SCR 9, par Sopinka J ("There is a danger that expert evidence will be misused and will distort the fact-finding process. Dressed up in scientific language which the jury does not easily understand and submitted through a witness of impressive antecedents, this evidence is apt to be accepted by the jury as being virtually infallible and as having more weight than it deserves.")
  7. ↑ White Burgess, supra, au para 18 ("The risk of “attornment to the opinion of the expertˮ is also exacerbated by the fact that expert evidence is resistant to effective cross-examination by counsel who are not experts in that field")
  8. ↑ White Burgess, supra, au para 18 ("Another well-known danger associated with the admissibility of expert evidence is that it may lead to an inordinate expenditure of time and money")
    Mohan, supra, au p. 21
  9. ↑ R c Sekhon, 2014 SCC 15 (CanLII), [2014] 1 SCR 272, par Moldaver J, au para 46
    R c Shafia, 2016 ONCA 812 (CanLII), 341 CCC (3d) 354, par Watt JA, au para 235
  10. ↑ , ibid., au para 46

Exigences pour qualifier un expert (Test Mohan)

La qualification d’un expert nécessite une enquête en deux étapes. Premièrement, les éléments de preuve doivent satisfaire aux quatre « seuils » d'admissibilité. Deuxièmement, le juge doit établir un équilibre coûts-avantages entre les risques et les avantages potentiels de l'admission des preuves et décider si les avantages l'emportent sur les risques.[1]

Pour qualifier une personne d'expert, la preuve doit répondre aux exigences de « Mohan » :[2]

  1. l'avis doit être « pertinent » ;
  2. l'opinion doit être « nécessaire » pour aider le juge des faits à tirer la bonne conclusion ;
  3. l'« absence » de toute autre règle d'exclusion ;
  4. les qualifications requises de l'expert proposé.

Le test de Mohan suppose que le domaine scientifique n’est pas nouveau. Lorsque l'objet est nouveau, contesté ou utilisé à des fins nouvelles, il existe une exigence supplémentaire que la partie présentant la preuve démontre que l'objet est fiable « à cette fin ».[3]

Approche blanche/abbaye de Mohan

L'approche analytique préférée du test de Mohan consiste à effectuer une analyse en deux étapes.Erreur de référence : Balise fermante </ref> manquante pour la balise <ref>

Deuxième étape - Portier

La deuxième étape concerne une « enquête de contrôle » au cours de laquelle le juge « doit identifier et peser des considérations concurrentes pour décider si, dans l'ensemble, l'admissibilité de la preuve est favorisée. »[4] Cette deuxième étape est en fait une analyse coûts-avantages.Erreur de référence : Balise fermante </ref> manquante pour la balise <ref> En l’absence d’erreur de principe ou de décision déraisonnable, la décision du juge sur la base d’un témoignage d’expert requiert la déférence.[5]

Impartiality

Expert evidence should be expected to be impartial to be admissible. There must not be any bias or appearance of bias.[6]

Weight Given to Expert Evidence

Where qualification is consented to by the other counsel, it does not permit the court to assign "weight beyond what the trial judge should otherwise attribute."[7] Weight is attributed by the court based on "reasons given for the expert opinion, the evidence bearing on the basis of the expert opinion and the extent of the expert’s expertise."[8]

Objections

Where the expert witness was not properly qualified and still gave evidence, their opinion may still be admissible absent objection from the opposing counsel.[9]

A failure of defence to make objections during trial are not likely obstacles to appeal since it is "foreseeable that defence counsel may fail to object to the testimony at the time the problematic statements are made."[10]

Expert Evidence Dangers

The courts "must be vigilant in monitoring and enforcing the proper scope of expert evidence" throughout the trial. Simply ruling on the Mohan criteria at the outset is not enough.[11]

Judge's must be cautious that the trial does not devolve into "trial by expert". The trier-of-fact must still be able to make "an effective and critical assessment of the evidence" that is based on "informed judgment" rather than blind faith in the expert's opinion.[12] To avoid this the courts as gatekeepers must watch out for:[13]

  • resistance to effective cross-examination by a non-expert counsel;
  • potential prejudice created by the expert's reliance on unproven material not subject to cross-examination;
  • the admission of "junk" science;
  • the risk of distraction from a "contest of experts";
  • an inordinate amount of time and money consumed by experts.
  • the likelihood of confusing the trier-of-fact;
  • the extent of impenetrable jargon.
  • the inability of trier-of-fact from making effective and critical assessment of the evidence.
Appellate Review

Given the "case-specific" nature of the test, the appellate court may intervene where the finding "is clearly unreasonable, contaminated by an error in principle or reflective of a material misapprehension of evidence."[14] The Court must show deferrence to the trial judge's decision.[15]

  1. ↑ R c Shafia, 2016 ONCA 812 (CanLII), 341 CCC (3d) 354, par Watt JA, au para 226
    R c Abbey, 2009 ONCA 624 (CanLII), 246 CCC (3d) 301, par Doherty JA
    Parliament v Conley, 2021 ONCA 261 (CanLII), 155 OR (3d) 161, par Harvison Young JA, au para 43
    White Burgess Langille Inman v Abbott and Haliburton Co, 2015 SCC 23 (CanLII), [2015] 2 SCR 182, par Cromwell J (7:0), aux paras 23to 24
  2. ↑ R c Mohan, 1994 CanLII 80 (SCC), [1994] 2 SCR 9, par Sopinka J (9:0)
    R c J-LJ, 2000 SCC 51 (CanLII), [2000] 2 SCR 600, par Binnie J
    R c Sekhon, 2014 SCC 15 (CanLII), [2014] 1 SCR 272, par Moldaver J (5:2), au para 43
  3. ↑ White Burgess, supra, au para 23 ("At the first step, the proponent of the evidence must establish the threshold requirements of admissibility. These are the four Mohan factors ... and in addition, in the case of an opinion based on novel or contested science or science used for a novel purpose, the reliability of the underlying science for that purpose: .... Relevance at this threshold stage refers to logical relevance: .. . Evidence that does not meet these threshold requirements should be excluded. Note that I would retain necessity as a threshold requirement: ...")
    JLJ, supra, at paras 33, 35 to 36, 47
    R c Trochym, 2007 SCC 6 (CanLII), [2007] 1 SCR 239, au para 27
  4. ↑ Farnham, supra, au para 81
    White, supra, au para 24 ("At the second discretionary gatekeeping step, the judge balances the potential risks and benefits of admitting the evidence in order to decide whether the potential benefits justify the risks. The required balancing exercise has been described in various ways. In Mohan, Sopinka J. spoke of the “reliability versus effect factor” (p. 21), while in J.-L.J., Binnie J. spoke about “relevance, reliability and necessity” being “measured against the counterweights of consumption of time, prejudice and confusion”: para. 47. Doherty J.A. summed it up well in Abbey, stating that the “trial judge must decide whether expert evidence that meets the preconditions to admissibility is sufficiently beneficial to the trial process to warrant its admission despite the potential harm to the trial process that may flow from the admission of the expert evidence”")
  5. ↑ R c Natsis, 2018 ONCA 425 (CanLII), 361 CCC (3d) 26, par Pardu JA, au para 16 ("I begin with the observation that, absent an error in principle or an unreasonable ruling, a trial judge’s decision as to the admissibility of expert evidence is entitled to deference")
    R c McManus, 2017 ONCA 188 (CanLII), 353 CCC (3d) 493, par van Rensburg JA, au para 68
  6. ↑ R c Docherty, 2010 ONSC 3628 (CanLII), [2010] OJ No 2460, par Wein J - father of defence counsel writes psych report, found invalid
  7. ↑ R c Strickland, 2013 NLCA 65 (CanLII), par Mercer JA (3:0)
  8. ↑ , ibid., au para 19
  9. ↑ See Opinion Evidence Outside of Qualification below
  10. ↑ Sekhon, supra, au para 48
  11. ↑ Sekhon, supra, au para 46
  12. ↑ White Burgess, supra, au para 18
  13. ↑ White Burgess, supra, au para 18
    Shafia, supra, au para 233 ("Consumption of time. Prejudice. Confusion. The danger that jurors will be unable to make an effective and critical assessment of the evidence. The complexity of the materials. The impenetrable jargon in which the opinion is clothed. Compromise of the trial process by unduly protracting and complicating proceedings:")
  14. ↑ Shafia, supra, au para 230 ("The case-specific nature of the Mohan inquiry has implications for the standard of appellate review. Appellate review is not precluded, as for example, where a finding of admissibility under Mohan is clearly unreasonable, contaminated by an error in principle or reflective of a material misapprehension of evidence.")
  15. ↑ Shafia, supra, au para 230

Relevance

Relevance require the judge to conduct a cost-benefit analysis to determine "whether its value is worth what is costs", which includes weighing the probative value against the prejudicial effect.[1]

The relevance requirement includes both logical relevance (the relationship between the evidence and the fact in issue it is being used to establish) and legal relevance (the probative value).[2] In the first stage of the analysis on threshold reliability, the focus is on logical relevance.[3]

Logical relevance requires that the evidence "have a tendency, as a matter of human experience and logic, to make the existence or non-existence of a fact in issue more or less likely than it would be without the evidence."[4]

Expert evidence can be relevant where it establishes motive to commit the offence.[5] It can also be relevant ot demonstrate animus towards the victim.[6]


It is not legally relevant for a qualified drug expert to say that they have never encountered a blind drug courier in their investigations.[7]

Anecdotal Evidence from Expert

Anecdotal evidence per se is not inadmissible through the expert, however, depending on the purpose of the expert testimony it may lack legal relevance and necessity.[8]

  1. ↑ R c Sekhon, 2014 SCC 15 (CanLII), [2014] 1 SCR 272, par Moldaver J, au para 44
    R c Mohan, 1994 CanLII 80 (SCC), [1994] 2 SCR 9, par Cory J, aux pp. 23-24
  2. ↑ R c AK, 1999 CanLII 3793 (ON CA), 137 CCC (3d) 225, par Charron JA
  3. ↑ White Burgess Langille Inman v Abbott and Haliburton Co, 2015 SCC 23 (CanLII), [2015] 2 SCR 182, par Cromwell J, au para 23
    R c Abbey, 2009 ONCA 624 (CanLII), 246 CCC (3d) 301, par Doherty JA, au para 82
    R c Shafia, 2016 ONCA 812 (CanLII), 341 CCC (3d) 354, par Watt JA, au para 227
  4. ↑ Abbey, supra, au para 82
    R c J-LJ, 2000 SCC 51 (CanLII), [2000] 2 SCR 600, par Binnie J (7:0), au para 47
    Shafia, supra, au para 227
  5. ↑ R c Ma, 1978 CanLII 2438 (ON CA), [1978] OJ No 1425, par Lacourciere JA
    R c Boucher, 2000 CanLII 6087 (QC CA), 149 CCC (3d) 429, par curiam (3:0)
    R c Wilson and Boswell, 2002 CanLII 49653 (ONSC), 166 CCC (3d) 294, par Kruzick J
  6. ↑ R c McLeod, [1982] OJ No 59(*pas de liens CanLII)
    Wilson and Boswell, supra
  7. ↑ Sekhon, supra, au para 49
  8. ↑ Sekhon, supra R c Burnett, 2018 ONCA 790 (CanLII), 367 CCC (3d) 65, par Watt JA (3:0), au para 58

Necessity

The necessity requirement is not a strict standard. It is necessary where it furnishes scientific information that is likely to be outside the experience and knowledge of the trier of fact.[1]

The expert evidence must likely outside the ordinary experience and knowledge of the trier of fact.[2] The evidence should not be necessary if “on the proven facts a judge or jury can form their own conclusions without help, then the opinion of [an] expert is unnecessary”.[3]

This criterion asks whether the trier-of-fact (or "ordinary people") can form a "correct judgment about the issue" without the assistance of persons with special knowledge.[4]

Merely being "helpful" is not sufficient.[5]

However, the purpose of this element is to "ensure that the dangers associated with expert evidence are not lightly tolerated" and that mere "helpfulness" is not sufficient.[6]

The subject-matter should be one that a lay person is "unlikely to form a correct judgment about it, if unassisted by persons with special knowledge."[7]

The purpose of the necessity requirement it to protect against the dangers of expert evidence, including the risk of usurping the trier-of-fact, the consumption of time, and consumption of expenses.[8]

  1. ↑ R c B(RH), 1994 CanLII 127 (SCC), [1994] 2 SCR 656, par McLachlin J (9:0)
  2. ↑ R c Burns, 1994 CanLII 127 (SCC), [1994] 1 SCR 656, par McLachlin J (9:0), aux paras 24 to 25
    R c Mohan, 1994 CanLII 80 (SCC), [1994] 2 SCR 9, par Sopinka J (9:0), aux pp. 414-415
  3. ↑ , ibid., au p. 23
    R c Sekhon, 2014 SCC 15 (CanLII), [2014] 1 SCR 272, par Moldaver J (5:2), au para 45
  4. ↑ Meady v Greyhound Canada Transportation Corp, 2015 ONCA 6 (CanLII), 329 OAC 173, par Strathy CJ, au para 33 ("The application of the necessity criterion asks whether the trier is able to form a correct judgment about the issue without the assistance of persons with special knowledge.")
    Bonisteel, 2008 BCCA 344 (CanLII), 236 CC (3d) 170, par Levine JA, au para 68
    R c Osmar, 2007 ONCA 50 (CanLII), 217 CCC (3d) 174, par Rosenberg JA, au para 68
  5. ↑ Mohan at p. 23 ("The word "helpful" is not quite appropriate and sets too low a standard.") Greyhound, supra at para 32
  6. ↑ White Burgess, supra, au para 21
  7. ↑ Kelliher (Village of) v Smith, 1931 CanLII 1 (SCC), [1931] SCR 672, par Lamont J (3:2)
    R c DD, 2000 SCC 43 (CanLII), [2000] 2 SCR 275, par Major J (4:3), au para 57
  8. ↑ Mohan, supra, au p. 24
    Sekhon, supra, au para 45
    DD, supra

Properly Qualified Expert

The burden is upon the party calling the witness to prove on a balance of probabilities that they are a "properly qualified expert."[1] The determination of whether a witness is "properly qualified" is based on a "case-specific determination."[2]

  1. ↑ R c Terceira, 1998 CanLII 2174 (ON CA), 123 CCC (3d) 1, par Finlayson JA aff'd at 142 CCC (3d) 95, 1999 CanLII 645 (SCC), par Iacobucci J
  2. ↑ R c Vander Wier, 2013 ONSC 7390 (CanLII), par Coats J, au para 13

Facteurs

Les facteurs à prendre en compte pour évaluer si le témoin est « correctement qualifié » comprennent :[1]

  • La manière dont le témoin a acquis les compétences et connaissances particulières sur lesquelles est fondée la demande ;
  • L'éducation formelle du témoin (c'est-à-dire diplômes ou certificats) ;
  • Les qualifications professionnelles du témoin (c'est-à-dire membre de l'Ordre des médecins et chirurgiens) ;
  • L'appartenance et la participation du témoin à des associations professionnelles liées à son témoignage proposé ;
  • Si le témoin a suivi des cours ou des séminaires supplémentaires liés aux domaines de preuve en litige ;
  • L'expérience du témoin dans le(s) domaine(s) proposé(s);
  • Si le témoin a enseigné ou écrit dans le(s) domaine(s) proposé(s) ;
  • Si, après avoir atteint un certain niveau d'expertise, le témoin a suivi la littérature dans le domaine ;
  • Si le témoin a déjà été qualifié pour témoigner dans le(s) domaine(s) proposé(s), y compris le nombre de fois et si le témoignage précédent a été contesté ;
  • Si le témoin n'a pas été qualifié pour témoigner dans le(s) domaine(s) proposé(s) et si oui, la(les) raison(s) ; et
  • Si la jurisprudence ou les textes juridiques antérieurs ont identifié le domaine contesté comme un domaine approprié pour le témoignage d'expert et, si oui, qui pourrait fournir le témoignage.
  1. ↑ R c Pham, 2013 ONSC 4903 (CanLII), 300 CCC (3d) 111, par Durno J, au para 31

Fiabilité

En l’absence d’erreur de principe ou de décision déraisonnable, la décision du juge sur la base d’un témoignage d’expert requiert la déférence.[1]

  1. ↑ R c Klassen, 2003 MBQB 253 (CanLII), [2003] MJ No 417, par Scurfield J, au para 26 - drug expert rejected

Experience and Education

An expert does not have to have practical experience.[1]

The essential requirement is that "he should be skilled ... that which he is called upon to give an opinion."[2]

No Prior Qualification

There is no special rule for "first time" experts that would render them any less eligible for qualification as an expert.[3]

Education

A formal education such as a university degree is not a necessary requirement to be an expert in an area.[4]

However, the expertise must be gained through some form of study or experience.[5] Deficiencies in expertise will usually go to weight not qualifications.[6]

Employment by Police Service

There is no impediment to qualification where the proposed expert is employed by police service.[7]

  1. ↑ e.g. R c Morgentaler (No. 2), 1973 CanLII 1462 (QC CQ), 14 CCC (2d) 450 (Que. S.C.), par Hugessen J - gynecologist testified as expert despite having not practiced for 10 years
  2. ↑ R c Korski, 2007 MBQB 184 (CanLII), 218 Man R (2d) 56, par Beard J, au para 15 citing McWilliams' Canadian Criminal Evidence
  3. ↑ R c Plourde, 2017 ABCA 367 (CanLII), par Slatter JA (3:0), au para 5
  4. ↑ R c Dugandzic, 1981 CanLII 3117 (ON CA), [1981] OJ No 1, 57 CCC (2d) 517, par Lacourcière JA (3:0) - chemistry degree not required to identify a still
  5. ↑ Dugandzic, supra
    R c Godfrey, 1974 ALTASCAD 43 (CanLII), 18 CCC (2d) 90 (Alta. S.C.A.D.), par Allen JA (2:1), aux pp. 102-104
  6. ↑ R c Marquard, 1993 CanLII 37 (SCC), [1993] 4 SCR 223, par McLachlin J (8:1), au p. 243
  7. ↑ Plourde, supra, au para 5

Independence, Impartiality and Lack of Bias

Evaluating Novel Fields

Novel sciences must be considered on a case-by-case basis. There are no fixed categories where the requirements for expert evidence have been met.[1] The courts must individually distinguish between new sciences and "junk" sciences. As such, needs "special scrutiny."[2]

There is no pre-condition that a particular field be "scientifically valid" or otherwise able to be validated by scientific methods.[3]

Novel sciences must only be qualified if it is (1) necessary and (2) reliable[4]

When evaluating scientific evidence, the Court should consider Daubert factors:[5]

  1. falsifiability of the theory
  2. peer review and publication of the theory
  3. known or potential rate of error and the existence of standards controlling the research on which the theory is based and
  4. general acceptance of the methodology underlying the theory in the scientific community.
Unsettled Theories

The evidence can still be admissible even if the scientific theory is open to debate or that there are exceptional cases to the theory.[6]

It is not necessary to establish that the field be one that is subject to "peer review."[7]

The fact that an area of scientific theory is open to debate and that exceptional cases fall outside the norm does not preclude the evidence from admissibility.[8]

Source of Expertise

Expertise "may be acquired through study."[9]

Depending on the subject, it may not be necessary that the expert has a university degree in the subject to be an expert.[10]

The absence of writing or publications will generally go to weight and not admissibility.[11]

An expert is entitled to develop that expertise by observations, by talking to other experts, and by general involvement in the field.[12]

  1. ↑ e.g. R c Lavallee, 1990 CanLII 95 (SCC), [1990] 1 SCR 852, par Wilson J battered wife syndrome accepted as science
  2. ↑ R c J-LJ, 2000 SCC 51 (CanLII), [2000] 2 SCR 600, par Binnie J (7:0)
  3. ↑ R c Shafia, 2016 ONCA 812 (CanLII), 341 CCC (3d) 354, par Watt JA, au para 240
    R c Abbey, 2009 ONCA 624 (ONCA), 246 CCC (3d) 301, [2009] OJ No 3534, par Doherty JA, au para 109
  4. ↑ R c Terceira, 1998 CanLII 2174 (ON CA), (1998) 123 CCC (3d) 1,, par Finlayson JA
  5. ↑ J-LJ, supra
  6. ↑ R c M(B), 1998 CanLII 13326 (ON CA), 130 CCC 353 (ONCA), par Rosenberg JA
  7. ↑ Abbey, supra, au para 97 - lower court erred in requiring peer review
  8. ↑ BM, supra ("The fact that a scientific theory is open to debate, however, or that exceptional cases fall outside the norm, does not preclude the admissibility of opinion evidence based on that theory.")
  9. ↑ McWilliams’ Canadian Criminal Evidence (4th) at 12:30.20.50. citing Mohan at 414
  10. ↑ R c Bulman, 2007 ONCA 169 (CanLII), [2007] OJ No 913 (CA), par Gillese JA, au para 7
  11. ↑ BM, supra, au para 71
  12. ↑ R c Plourde, 2017 ABCA 367 (CanLII), par Slatter JA, au para 6 - ("An expert on drug activity is entitled to develop that expertise by observations of the drug trade, by talking to other experts, and by general involvement in policing of the drug trade.")

Cost/Benefit Analysis

The secondary stage of analysis is the gatekeeping function of the court to exclude certain types of expert evidence.

The role as "gatekeeper" does not end once the judge determines that the expert is permitted to testify based on their qualifications and the content of their report.[1] The judge must maintain a "cautious delineation of the scope of the... evidence and strict adherence to those boundaries, if the evidence is admitted."[2] The residual discretion to exclude evidence where the prejudicial effect outweighs the probative value continues throughout the testimony.[3]

Discretionary Exclusion of Qualified Expert Evidence

Qualified expert evidence can nonetheless be excluded if:[4]

  1. the evidence would tend to usurp the duty of the trier of fact
  2. the prejudicial effect outweighs the probative value
  3. the time required outweighs its probative value
  4. the cost required outweighs the probative value
  5. the influence of the evidence outweighs the evidence's reliability.

The proposed expert must have some indicia of scientific knowledge. It cannot be admitted if the witness is giving personal opinions based on their experience or knowledge from "some" literature and interviews.[5]

Other Qualification Issues

A final draft going to peer review is relevant evidence for disclosure.[6]

Defence Obligation to Disclose

Given the different disclosure obligations between Crown and defence. There may be times where the Crown would need to disclose drafts of the expert reports while defence would not.[7]

The defence however are required to disclose anything that the exported used to form the basis of their opinion.[8]

  1. ↑ Bruff-Murphy v Gunawardena, 2017 ONCA 502 (CanLII), 414 DLR (4th) 65, par Hourigan JA, aux paras 62 to 66, leave to appeal refused, [2017] S.C.C.A. No. 343
    R c Sekhon, 2014 SCC 15 (CanLII), [2014] 1 SCR 272, par Moldaver J, aux paras 46 to 47
    Parliament v Conley, 2021 ONCA 261 (CanLII), 155 OR (3d) 161, par Harvison Young JA, au para 45
  2. ↑ , ibid. at paras 45 to 47
  3. ↑ , ibid. at para 48
    R c White, 2011 SCC 13 (CanLII), [2011] 1 SCR 433, par Rothstein J, au para 50
    R c Bingley, 2017 SCC 12 (CanLII), [2017] 1 SCR 170, par McLachlin CJ, au para 30
  4. ↑ , ibid.
  5. ↑ R c Bedford, 2000 CanLII 2487 (ON CA), 143 CCC (3d) 311, par Finlayson JA (3:0)
  6. ↑ R c Natsis, 2018 ONCA 425 (CanLII), 361 CCC (3d) 26, par Pardu JA, aux paras 25 to 34
  7. ↑ R c CG, 2018 ONSC 6204 (CanLII), par Bell J
  8. ↑ , ibid., au para 16 ("... Although the issue in Friskie was the extent to which the Crown was entitled to disclosure of materials provided to a defence expert, it is clear that what the Crown was seeking and what the court ultimately ordered to be disclosed were materials that formed the foundation of the expert’s report. Once an expert witness takes the stand, that witness can no longer be characterized as offering private advice to a party; rather, they are offering an opinion for the assistance of the court and the opposing party must be given access to the foundation of such opinions to test them adequately ..."}}
    R c Friskie, 2001 CanLII 392 (SK PC), 49 WCB (2d) 375, par Snell J
    R c Stone, 1999 CanLII 688 (SCC), [1999] 2 SCR 290, par Bastarache J, au para 99
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