Court File and Parties

BARRIE COURT FILE NO.: CV-11-0693 DATE: 20190523 ONTARIO SUPERIOR COURT OF JUSTICE

BETWEEN:

Jacob James McIsaac by his Litigation Guardian, Cheryl McIsaac and Joseph McIsaac Plaintiffs – and – Dr. James Alastair MacKinnon, Dr. Patricia Ann Bayliss, Dr. Shujauddin Fazalurrhahman Hafiz, Dr. John Timothy Feltis, Dr. Patricia Cresswell Parkin, Dr. Michael Szeto, Dr. Stanley Edgar Read, Dr. Chantelle Bernadette Samson Barnard, Dr. Manuel Carcao, Dr. Beverley Lynette Burt Bowes, Dr. Mohamed Abdelhaleem, Lila Freedman, in her capacity as Administrator of The Estate of Dr. Melvin Harris Freedman, Deceased, Dr. John Doe, Credit Valley Hospital and The Hospital for Sick Children Defendants

Counsel: James Vigmond, Adam Little, and Karen Vigmond for the Plaintiff Thomas Curry, Jaan Lilles, Andrew Porter and Amy Sherrard, for the Defendant, Dr. James Alastair MacKinnon

HEARD: May 21, 2019

RULING RE: motion to disqualify expert witness

CHARNEY J.:

Introduction

[1] This is a medical malpractice action arising from the defendant’s medical treatment of the minor plaintiff in the months after his birth. The infant plaintiff’s parents are also plaintiffs in this action.

[2] The plaintiffs allege that the defendant was negligent in his care of the infant plaintiff. They allege that the defendant failed to properly communicate test results to physicians at the Hospital for Sick Children and this resulted in the delayed diagnosis and treatment of the plaintiff. The plaintiffs allege that this negligence, which resulted in a 40 day delay in treatment, caused the infant plaintiff’s severe developmental disabilities.

[3] In an Agreed Statement of Facts, the defendant has acknowledged that his treatment of the plaintiff fell below the standard of care, but the issues of causation and damages are still contested.

Issue

[4] The infant plaintiff was born in 2001 with a rare genetic metabolic disorder, Transcobalamin II deficiency, or TCII. TCII impacts a portion of the body’s process for metabolizing proteins and facilitating the transport of vitamin B12 from the digestive tract to the tissues in the body. TCII is treated with vitamin B12 injections.

[5] The infant plaintiff also has significant cognitive deficits. The first question for the jury will be whether these cognitive deficits were caused by the 40 day delay in treatment that resulted from the defendant’s failure to properly communicate test results to the infant plaintiff’s physicians at the Hospital for Sick Children.

[6] Both sides have filed expert reports providing an opinion on causation.

[7] One of the expert reports filed by the plaintiffs is by Dr. Michael Freeman, an epidemiologist. The defendant has brought this motion to disqualify Dr. Freeman as an expert witness on several grounds, including that he lacks any specialized knowledge or expertise related to the metabolic disorder at issue, his “comparative risk” methodology lies outside the mainstream study of epidemiology, and his report discloses that he is an advocate and not an objective expert.

[8] The defendant argues that Dr. Freeman’s proposed evidence is not necessary and its admission outweighs any possible benefit.

[9] The defendant points to several cases in the United States, and one in Canada, in which Dr. Freeman was not permitted to testify as an expert witness, see for example: Porter v. Smithkline Beecham Corporation, Court of Common Pleas of Philadelphia County, Civil Trial Division, September Term 2007 No. 03275; Deatherage v. Schindler Elevator Corp., 2018 U.S. Dist. LEXIS 109080; Eisenbise v. Crown Equip. Corp., 260 F.Supp. 3d 1250; Tucker v. Harrison, 2013 IN S.Ct. Briefs 42625; and Brough v. Yipp, 2016 CarswellAlta 3546.

[10] The plaintiff responds that the number of cases in the United States and Canada in which Dr. Freeman has been qualified as an expert and given evidence far exceeds the number of cases in which his evidence was excluded. He has given evidence in cases in Canada on causation involving a number of different topics, including: whether a low impact rear end collision caused a neck injury, probabilities of various causes of a stroke, causation between a chiropractic adjustment and cauda equine syndrome, causation between endoscopy and vertebral artery dissection causing a subarachnoid haemorrhage, and causation between a motor vehicle accident and a subsequent stroke, see: Jensen v. Thompson, 2002 ABQB 1066; Andersen v. Queen Elizabeth II Health Sciences Centre, 2011 NSSC 226; Malinowski v. Schneider, 2010 ABQB 734; Kirby v Raman, 2014 NLTD(G) 154; and McKenzie v. Lloyd, 2016 BCSC 1745.

[11] On May 21, 2019 a voir dire was conducted in the absence of the jury to determine the issue of Dr. Freeman’s qualifications to testify as an expert witness. On May 22, 2019 I gave brief oral reasons granting the defendant’s motion to disqualify Dr. Freeman, indicating that fuller written reasons would follow. These are those reasons.

Legal Principles

[12] Proposed expert evidence must meet the four preconditions established by the Supreme Court of Canada in R. v. Mohan, [1994] 2 SCR 9, before being admitted for consideration by the trier of fact. These criteria are: (i) relevance, (ii) necessity in assisting the trier of fact, (iii) absence of an exclusionary rule (other than the opinion rule), and (iv) a properly qualified expert. Provided the applicant satisfies the court as to the existence of the four Mohan criteria, the court will go on to consider whether the proposed opinion evidence is sufficiently beneficial to the trial process to warrant admission, despite the “potential harm to the trial process that may flow from the admission of the expert evidence”: R. v. Abbey, 2009 ONCA 624, at para. 76.

[13] Moreover, the Supreme Court of Canada has confirmed that issues such as independence and impartiality go to the admissibility of evidence, and not just its weight. A lack of independence or impartiality can lead to inadmissibility in certain circumstances: White Burgess Langille Inman v. Abbott and Haliburton Co., [2015] 2 SCR 182, 2015 SCC 23, at paras. 40 and 45.

[14] The requirement that a proposed expert possesses relevant expertise, independence and objectivity is codified in Rule 4.1.01 of the Rules of Civil Procedure, R.R.O. 1990, Reg. 194. Subrule 4.1.01(1)(b) expressly provides that it is the duty of every expert engaged on behalf of a party “to provide opinion evidence that is related only to matters that are within the expert’s area of expertise.” (emphasis added)

[15] As Boswell J. stated in R. v. Osborne, 2019 ONSC 907, at para. 46:

A proposed expert must have demonstrated experience, through education, training and practice, in the specific subject matter of the proposed opinion. A review of the relevant research literature on a subject matter “at the margins of the witness’s education, training and experience, or in a closely related field of study, does not render one an expert… Absent demonstrated experience, the court runs the risk that the proposed witness is not offering an independent opinion, but rather is merely relying on the opinions of others.” See S.K. Fenton, “A Properly Qualified Expert”, National Criminal Law Program, July 2015, Section S.1, page 5. See also R. v. Mathisen, 2008 ONCA 747, paras. 126-127.

[16] In Mathisen, the Ontario Court of Appeal, at para. 126, adopted the following statement from the trial judge:

In my opinion, it is inappropriate to find a witness to be a properly qualified expert where the source of the proposed expertise comes from reviewing literature – albeit with a facility that most of us would not have – but in respect of a subject matter that is outside the field of that witnesses’ (sic) education and training.

[17] The Court of Appeal concluded, at para. 47: “[W]ere it otherwise, courts would be obliged to qualify as experts persons who could not offer real opinions of their own on any given subject but could only point to what they had read.”

Analysis

[18] The admissibility of Dr. Freeman’s expert evidence turns largely on the fourth of the Mohan criteria: does Dr. Freeman’s proposed evidence fall within his expertise as an epidemiologist?

[19] The infant plaintiff has a rare genetic metabolic disorder. Dr. Freeman has acknowledged that he has no expertise in metabolics, and that, prior to being retained to give an opinion in this case, he had never heard of Transcobalamin II deficiency, let alone treated a child with this disorder. Dr. Freeman is not qualified as a clinical physician, and has never treated patients.

[20] The infant plaintiff also has significant cognitive impairment. Dr. Freeman has acknowledged that he has no expertise in neurology.

[21] The medical question in this case is whether the 40 day delay in treating the infant plaintiff’s metabolic disorder caused his significant cognitive impairment. The issue on this motion is whether Dr. Freeman’s expertise as an epidemiologist qualifies him to give an opinion on this medical question, even though he has no expertise in metabolics or neurology.

[22] Dr. Freeman has filed four expert reports dated March 19, 2018, August 27, 2018, January 9, 2019 and May 15, 2019. In the first report Dr. Freeman defines epidemiology as “the scientific study of the cause of disease and injury in populations, including prevalence, risk and incidence in specific populations”. He indicates that the “methods applied in this report are consistent with those outlined in the Reference Guide on Epidemiology, from the Reference Manual on Scientific Evidence published by the Federal Judicial Center and the National Academies of Science (3d edition, 2011) (the Reference Guide).

[23] The Reference Guide relied on by Dr. Freeman sets out the following, more complete, explanation of the role of epidemiology under the heading “What Role Does Epidemiology Play in Proving Specific Causation?” (at pp. 608-609):

Epidemiology is concerned with the incidence of disease in populations, and epidemiologic studies do not address the question of the cause of an individual’s disease. The question, often referred to as specific causation, is beyond the domain of the science of epidemiology. Epidemiology has its limits at the point where an inference is made that the relationship between an agent and a disease is causal (general causation) and where the magnitude of excess risk attributed to the agent has been determined; that is, epidemiologists investigate whether an agent can cause a disease, not whether an agent did cause a specific plaintiff’s disease.

[24] While epidemiological evidence is about “general causation” rather than “specific causation”, it may still be relevant to the question of individual causation. As the Reference Guide states (at p. 611): “An agent cannot be considered to cause the illness of a specific person unless it is recognized as a cause of that disease in general”. Thus, a scientifically valid epidemiological study may be admissible evidence if it makes causation in an individual case more or less likely. For example, the fact that asbestos is known to cause lung cancer makes it more likely that a specific individual exposed to asbestos developed lung cancer as a result of that exposure. Exposure is not proof of causation, but evidence that may support a conclusion of causation. The Reference Guide indicates (at p. 612) that this analysis requires “significant assumptions and important caveats that require explication” including “a valid study and risk estimate” and “similarity among study subjects and plaintiff”.

[25] The limitation of epidemiological evidence on the issue of causation in individual cases has been noted in other cases. For example, in Andersen v. St. Jude Medical, Inc., 2012 ONSC 3660, Lax J. stated at paras. 393 – 395:

Given the importance of epidemiological evidence in this case, I think it is necessary for me to articulate its limitations in determining causation. Epidemiology is the study, control and prevention of disease and other health-related outcomes in populations, rather than in individuals.

The Ontario Workplace Safety and Insurance Tribunal (WSIAT) has considered epidemiological evidence on many occasions, and I believe its words of caution are apposite here. In Decision No. 1685/04, the WSIAT stated some relevant principles with respect to epidemiological evidence (the decision was related to workers who developed cancer after exposure to asbestos):

a. “Epidemiology cannot determine which particular factor caused a particular person’s disease but only what factors are statistically associated with the occurrence of disease in groups of people”. b. “Since epidemiology studies populations, not individuals, it cannot prove that a particular worker’s cancer was caused by the studied exposure”. c. The converse is also true: epidemiology cannot establish that the adverse event was not caused in a particular worker. “Epidemiology’s usefulness in a claim relates more to issues of risk and the studies cannot prove or disprove causation in an individual case”.

As such, epidemiological evidence ought not to be considered determinative in respect of causation in individuals…

[26] A more thorough discussion of epidemiology is found in Perell J.’s decision in Wise v Abbott Laboratories, Limited, 2016 ONSC 7275, at paras. 115 – 147.

[27] It is important to understand the scope and limits of epidemiology in order to decide whether the opinions proffered by Dr. Freeman fall within the scope of his expertise as an epidemiologist.

[28] Dr. Freeman begins his opinion by setting out “the three fundamental elements of an injury causation analysis” as follows:

1. Whether the injury mechanism had the potential to cause the injury in question (general causation) and if known, the magnitude of that potential (risk);
2. The degree of temporal proximity between the injury mechanism and the onset of the symptoms reasonably indicating the presence of the injury; and
3. Whether there is a more likely alternative explanation for the occurrence of the injury at the same point in time, versus the investigated cause (also known as a differential etiology/diagnosis). The alternative or competing cause is quantified for the individual, given their predictive characteristics and the temporal relationship quantified in step 2.

[29] It is immediately apparent that Dr. Freeman’s own expertise would not enable him to answer any of these questions. He answers each of these questions by reviewing the expert reports filed by the parties in this case and the articles referenced in those reports. None of these articles purports to be an epidemiological study.

[30] Based on his review of these reports and articles, he answers the first question: “it has been previously established that a delay in diagnosis of TCII deficiency is a well-established plausible cause of permanent neurological impairment.”

[31] He makes no effort to answer the second question related to “temporal proximity” between the injury mechanism and the symptoms indicating the injury, and merely notes that there was a delay of 50 days between diagnosis of TCII and treatment.

[32] With respect to the third element, he concludes that the causation opinions expressed by the plaintiffs’ other experts are, in his opinion, “supported by the medical literature on the topic”.

[33] Dr. Freeman takes issue with the causation opinion expressed by the defendant’s expert, Dr. Levy, on the basis that it contains a “shocking misuse of epidemiological principles and data, based entirely on logical fallacy and improper use of the medical literature”. He concludes that Dr. Levy’s conclusions are “fatally flawed and meaningless” due to “logical ellipses”.

[34] Dr. Freeman concludes: “the only conclusion that can be drawn from Dr. Levy’s case analysis that is applicable to Jacob is that there is a 63% probability that had he been treated promptly he would have had a good neurological outcome (ie. he would be normal)”. Dr. Freeman does not indicate whether this 63% figure is a scientifically valid epidemiological conclusion, or just a point intended to undermine Dr. Levy’s analysis.

[35] Finally, Dr. Freeman offers an opinion on the cause of the infant plaintiff’s cognitive delay, stating that, in his opinion, based on his review of the plaintiff’s expert reports, “there is sufficient evidence to conclude, on a more probably than not basis…that Jacob’s neurological impairments were caused by the 50 day delay in diagnosis of his TCII deficiency”.

[36] I do have some concern with regard to some of the intemperate language employed by Dr. Freeman, and I share the view of counsel for the defendant that this language discloses a degree of advocacy and partisanship that calls into question Dr. Freeman’s objectivity.

[37] I would not, however, disqualify Dr. Freeman on that ground alone. My main concern is this: as I read Dr. Freeman’s reports, he does not purport to conduct his own epidemiological study. Rather, he reviews the reports submitted by the other experts to this litigation and indicates his preference for the opinions of the plaintiffs’ experts and critiques the opinions of the defendant’s expert. It is for the jury to decide which of the experts’ opinions it will accept, and it is not for another expert to tell the jury which of the competing experts is more reliable. That is really all Dr. Freeman is doing in his report. His opinions are not independent, but depend entirely on his review of the other opinions prepared by the plaintiffs’ experts. His lack of expertise in either metabolics or neurology disqualifies him from declaring a winner in the debate between the two sides.

[38] Dr. Freeman does not limit his opinion to general causation, but purports to offer an opinion on specific causation, which, as noted by the Reference Guide, is beyond the scope of epidemiology.

[39] These concerns (lack of objectivity, giving opinions outside of the scope of his expertise and purporting to opine on which of the other experts is right) permeate all of Dr. Freeman’s reports. Another example appears in Dr. Freeman’s final report dated May 15, 2019, and relates to a debate between Dr. Levy and the plaintiff’s expert in paediatric metabolic disease, Dr. Geraghty. Dr. Geraghty provided an opinion, based on his expertise in metabolics, that the delay in the infant plaintiff’s diagnosis and treatment likely resulted in his poor clinical outcome. Dr. Levy and Dr. Geraghty traded reports dealing with the issue of whether the medical literature relating to TCII supported their respective opinions and conclusions.

[40] Dr. Freeman steps into the debate between Dr. Levy and Dr. Geraghty. Dr. Freeman asserts that “Dr. Levy’s assertion that literature does not support Dr. Geraghty’s opinion on Jacob’s presentation is patently false.” Given Dr. Freeman’s lack of expertise in either metabolics or neurology, it is not within the scope of his expertise to comment on which of the two competing metabolic experts is right.

[41] Some of Dr. Freeman’s opinions do fall within his expertise as an epidemiologist, and I have considered whether it is possible to parse Dr. Freeman’s evidence to permit him to testify about matters within his scope of expertise but preclude him from going outside his expertise. In my view, however, the areas of his proposed opinion evidence that are outside the scope of his expertise are inextricably bound with the areas that might fall within that scope, and it is not possible to surgically separate them so as to permit him to testify.

[42] The plaintiffs assert that if Dr. Levy is permitted to provide opinions on causation based on medical articles, the plaintiffs must be permitted to call rebuttal evidence. While I accept the premise of the plaintiffs’ position, it is clear from the expert reports that Dr. Geraghty goes head to head with Dr. Levy on the issue of whether the articles and studies relied on by Dr. Levy actually support his conclusion on causation. All the points made by Dr. Freeman appear to be covered by Dr. Geraghty. Given this evidence by Dr. Geraghty, Dr. Freeman’s evidence is not necessary. At best, it can only repeat Dr. Geraghty.

Conclusion

[43] For these reasons, the defendant’s motion to disqualify Dr. Freeman’s is allowed and he will not be permitted to testify.

Justice R.E. Charney

Released: May 23, 2019