THE EXPERT WITNESS IN A MILD TRAUMATIC BRAIN INJURY (MTBI) CASE
From an article published in the March 2000 edition of The Verdict
by Michael Slater
Mr. Justice Dubin, Ontario Court of Appeal
A mild traumatic brain injury (MTBI) case presents an excellent opportunity for the trial lawyer to use the authoritative literature to cross-examine defence medical experts. This approach can convincingly demonstrate to the trier of fact that the physical, cognitive, behavioural and emotional symptoms experienced by the plaintiff are recognized to be a consequence of MTBI by leading experts in the fields of neurology, neuropsychiatry, and neuropsychology.
The Expert Witness
The role of the expert witness is to assist the trier of fact in areas where specialized knowledge is required - areas where the Judge or juror would be unlikely to form a correct judgment without assistance from an expert. The two elements necessary to justify the admission of expert testimony were enunciated by Lamont, J., in the majority judgment of The Supreme Court of Canada in Kelliher v. Smith: 1
- The subject-matter of the inquiry must be such that ordinary people are unlikely to form a correct judgment about it, if unassisted by persons with special knowledge.
- The witness offering expert evidence must have gained his special knowledge by a course of study or previous habit which secures his habitual familiarity with the matter in hand.
In The Supreme Court of Canada decision in R. v. Abbey, Dickson, J. described the role of the expert witness in the following way:
With respect to matters calling for special knowledge, an expert in the field may draw inferences and state his opinion. An expertâs function is precisely this: to provide the judge and jury with a ready-made inference which the judge and jury, due to the technical nature of the facts, are unable to formulate. ÎAn expertâs opinion is admissible to furnish the Court with scientific information which is likely to be outside the experience and knowledge of a judge or jury. If on the proven facts a judge or jury can form their own conclusions without help, then the opinion of the expert is unnecessary.â R .v Turner (1974), 60 Crim.App. R. 80 at p. 83, per Lawton, J.2
More recently, authors Sopinka, Lederman and Bryant, in their text, The Law of Evidence in Canada, comment that: "The hallmark of admissibility simply should be whether the expertsâ testimony would be helpful to the tribunal."3
Clearly where the expert assumes the role being an advocate, the trier of fact will give little if any weight to the expert's opinion. For this reason it is important to consider the guidelines referred to in Ikarian Reefer: National Justice Compania Naviera SA v. Prudential Assurance Co. Ltd.4 for weighing the credibility and admissibility of expert evidence. These guidelines were summarized in Perricone v. Baldassarra:5
- Expert evidence presented to the court should be, and should be seen to be, the independent product of the expert uninfluenced as to form or content by the exigencies of litigation.
An expert should provide independent assistance to the court by objective unbiased opinion in relation to matters within his or her expertise. An expert witness should never assume a role of advocate.
An expert should state the facts or assumptions on which the opinion is based and should not omit to consider material facts which detract from that opinion.
An expert should make it clear when a particular question or issue falls outside of the expert's expertise.
- If an expert's opinion is not properly researched because insufficient data is available, this must be stated with an indication that the opinion is no more than a provisional one.
Cross-examination of an expert witness is really no different from that conducted with any other witness. While the expert may employ specialized concepts and technical jargon in expressing an opinion, nevertheless, the opinion must be logical, make progressive sense and be comprehensible to the trier of fact.6 A proper direct examination should accomplish these objectives. The goal of cross-examination is to undermine the foundation laid in direct examination. The usual approach to the cross-examination of an expert witness employs questions designed to establish the following:
The expert is limited as to his education, qualifications, knowledge and experience;
The expert doesn't teach, conduct research, or publish and doesn't keep up with advances in the field through continuing education, conferences, etc.
The opinion is founded on incomplete or inaccurate information provided to the expert by the lawyer or other sources;
The opinion is based on hypothetical assumptions that are incomplete or inadequate;
The expert has employed inappropriate or outdated methodology;
Prior statements, testimony, published papers, expert reports or seminar presentations of the expert are inconsistent with the opinion presented at trial;
The expert harbors an intellectual bias or hidden motivation for testifying.7
The expert has not conducted a personal examination or assessment of the patient that may be contrary to ethical guidelines established by the expert's professional governing body. For example, the American Psychological Association has included the following section in their Ethical Principles of Psychologists and Code of Conduct:
7.02 Forensic Assessments. (a) Psychologists' forensic assessments, recommendations, and reports are based on information and techniques (including personal interviews of the individual, when appropriate) sufficient to provide appropriate substantiation for their findings. (See also Standards 1.03, Professional and Scientific Relationship; 1.23, Documentation of Professional and Scientific Work; 2.01, Evaluation, Diagnosis, and Interventions in Professional Context; and 2.05, Interpreting Assessment Results.) (b) Except as noted in (c), below, psychologists provide written or oral forensic reports or testimony of the psychological characteristics of an individual only after they have conducted an examination of the individual adequate to support their statements or conclusions.
(c) When, despite reasonable efforts, such an examination is not feasible, psychologists clarify the impact of their limited information on the reliability and validity of their reports and testimony, and they appropriately limit the nature and extent of their conclusions or recommendations.
Use of Authoritative Literature in the Examination of Expert Witnesses
The use of authoritative literature such as texts, journal articles, and other scholarly publications is unique to the examination of expert witnesses. The law in this area was canvassed in Privest Properties Ltd. v. Foundation Co. of Canada,8 where Drost, J. makes the following comment:
In my opinion, the assessment of reliability and trustworthiness of expert opinion evidence involves very different considerations from those required in the case of factual evidence. In the case of expert opinion evidence, the need for cross-examination is, if anything, greater than in factual situations, because the trier of fact is likely to be in a poor position to assess the credibility of a scientific opinion without the assistance of cross-examination by opposing counsel, or to adopt the felicitous phrase employed by the late Mr. Justice McColl in Abermin Corp. v. Granges Exploration Ltd. (10 August 1990), Vancouver Reg. C884398 (B.C.S.C.), without exposing the opinion '... to the vagaries of opposing counsel's(sic) inquiring minds'.
Drost, J. adopts the conventional rule expressed in the oft-cited reasons of Mr. Justice Beck in R. v. Anderson:
I think an expert witness may be examined as to what is in the books. Medical works are produced which are recognized by the profession as standard authorities. An expert witness is being examined, who gives evidence as to specified diseases and their remedies. It is found by reference that his statements are at variance with what is laid down by the best authors on the same subject. Surely it must be the right of counsel to confront the witness with books written by scientific men [or women], leaders in their profession, for the purpose of showing either that the witness is mistaken, or that he may explain and reconcile, if he can, the real or apparent difference between what he has said and what is found in the books. If it was otherwise, men of insufficient learning, or veritable quacks, might palm off their crude opinions on juries as scientific knowledge.9
Use of Authoritative Literature in Direct Examination
In direct examination "the expert is permitted to refer to authoritative treatises and the like, and any portion of such texts upon which the witness relies is admissible into evidence."10 In R. v. Anderson,11 Beck, J. stated the basis for the admissibility of texts as the foundation of the expert's own opinion:
When a medical man or other person professing some science is called as an expert witness, it is his opinion and his opinion only that can be properly put before the jury. Just as in the case of a witness called to prove a fact, it is proper in direct examination to ask him not merely to state the fact, but also how he came by the knowledge of the fact, so in the case of an expert witness called to give an opinion, he may in direct examination be asked how he came by his opinion. An expert medical witness may, therefore, upon giving his opinion, state in direct examination that he bases his opinion partly upon his own experience and partly upon the opinions of text-writers who are recognized by the medical profession at large as of authority. I think he may name the text-writers. I think he may add that his opinion and that of the text-writers named accords. Further, I see no good reason why such an expert witness should not be permitted, while in the box, to refer to such text-books as he chooses, in order, by the aid which they will give him, in addition to his other means of forming an opinion, to enable him to express an opinion; and again, that the witness having expressly adopted as his own the opinion of a text-writer, may himself read the text as expressing his own opinion.
In a similar vein, Drost, J. refers to the following comments by the authors of The Law of Evidence in Canada:
Peculiar to the examination of experts is the utilization of textbooks. In support of any theory, an expert is permitted to refer to authoritative treatises and the like, and any portion of such texts upon which the witness relies is admissible into evidence. Moreover, it appears that, if a written work forms the basis of the expert's opinion, then counsel is allowed to read extracts to the expert and obtain his or her judgment on them. The written view of the author thereby becomes the opinion of the witness. If the witness does not adopt the writing as being authoritative and in accord with the witness' own opinion, nothing may be read from the text, for that would be tolerating the admissibility of pure hearsay. 12
Use of Authoritative Literature in Cross-Examination
A powerful weapon in the cross-examination of the expert witness involves the careful use of the authoritative literature to weaken the testimony of the opposing expert and to elicit testimony favourable to the cross-examiner - to, in effect, transform the opposing expert into your own tourguide through the authoritative literature. In cross-examination the expert may be questioned on any text or other publication which he acknowledges as authoritative or recognizes as a standard work in his field. The cross-examiner is then permitted to read from the authority to test the opinion of the expert. The expert cannot be cross-examined about any text or authority, which he does not regard as authoritative.13,14,15 The evidentiary justification for this rule of cross-examination is summarized in The Law of Evidence in Canada:16
Learned treatises may be used in a similar way in cross-examination of the expert to confront him with an authoritative opinion which contradicts the view expressed by the witness on the stand...
By so doing, the treatise is not used for the hearsay purpose of proving the truth of the opinion contained therein, but as a means of testing the value of the expert witness' conclusion. It becomes not positive evidence, but as in the case of the cross-examining tool of prior inconsistent statements, it is utilized to challenge the expert's credibility; to test whether the witness has intelligently and competently read and applied what has been authoritatively written on the subject. If the witness adopts a passage in the test, it is the expert and not the text writer's opinion that is admitted into evidence.
It is important to note that it is immaterial that the expert witness does not agree with or acknowledge the validity of the particular published work, only that he agrees that it is regarded in his field of expertise as an authoritative source. In the Privest Properties Ltd. case, Drost, J. considered whether it makes any difference whether, before permitting cross-examination on the particular writing from the text or journal, the expert recognizes the text or journal as authoritative or merely recognizes the authority of the author: There are cases that support either conclusion, and it seems to me that it becomes a question of fact in each instance. Does the witness recognize the authority of - as distinct from accepting the validity of - the particular writing, whether due to the status of the text or journal from which the writing is taken or due to his or her recognition of the status and authority of the author:
In any event, it is apparent that the traditional rule does little damage to the hearsay rule. No textual opinion offered in chief or in cross-examination is admissible unless an expert witness adopts it as his own.17
Cross-examination of an expert by utilization of the authoritative literature is an exception to the rule that you do not ask a question in cross-examination unless you know the answer. The literature keeps the expert honest and provides an opportunity to put your case before the trier of fact without calling any additional viva-voce evidence that would be subject to further cross-examination. When an expert is asked to agree with an extract from a text or other such publication that the expert acknowledges as authoritative, the reply will be of assistance to the examiner, regardless of the answer. If the expert agrees with the opinion expressed in the extract, then it forms part of the evidence and strengthens your case. Having the opposing expert confirm the authority of the opinions expressed in the text, journal or other publication in cross-examination will have a much greater impact than the same evidence given in direct examination. If the expert disagrees with the opinion expressed by the authoritative source, then the expert's credibility can be compromised, thereby weakening the opposition's case. While an opinion that is not adopted by the expert does not form part of the evidence at the trial, the examiner has at least had the benefit of placing an opinion from an authoritative source before the trier of fact that is contrary to the opinion expressed by the opposing expert.
Some Basic Points to Consider in Cross-Examination of Defence Expert in a Mild Traumatic Brain Injury Case18
Review report of defence expert with your own expert. What questions would your expert ask of opposing expert?
Locate prior statements, testimony, published papers, expert reports, seminar presentations, etc. of expert witness that are inconsistent with expert's opinion.
Request copies of expert's data and other facts on which the opinion is based that are not included with the report.
Did the expert employ inappropriate or outdated methodology?
Is the opinion founded on incomplete or inaccurate information provided to the expert by the lawyer or other sources?
Is the opinion based on hypothetical assumptions that are incomplete or inadequate?
Were inappropriate statements made by expert to client during evaluation?
Does the expert harbor an intellectual bias or hidden motivation?
Review educational and professional background of the expert. Is expert lacking in education, qualifications, knowledge and experience in MTBI?
Does the expert teach or conduct research in MTBI?
Has the expert written any books or articles on MTBI?
Does the expert keep up with advances in the field through continuing education, conferences, etc.?
Has the expert ever treated any patients with MTBI?
Research authoritative literature on MTBI.
Is expert familiar with MTBI literature?
What articles, texts, journals, etc. does the expert consider authoritative?
What publications does expert subscribe to? What's on the expert's bookshelves?
What information has expert reviewed? Is it all contained in the file?
Examine the entire file of the expert prior to cross-examination. Look for notes, draft reports, correspondence with counsel, investigation reports, journal articles, etc. Is information missing that should be there?
Has expert had discussions with anyone other than counsel concerning the case?
Does the expert testify for both plaintiff and the defence?
What is MTBI?
Is it necessary to lose consciousness or is a dazed or altered state of consciousness sufficient? (see "Definition of mild traumatic brain injury" in Journal of Head Trauma Rehabilitation, 1986, 8(3) 86. Definition requires only one of the following for MTBI: 1) any period of loss of consciousness, 2) any loss of memory for events immediately before or after the accident, 3) any alteration in consciousness (e.g., feeling dazed, disoriented or confused), or 4) a focal neurological deficit that may or may not be transient)
What is the pathophysiological mechanism responsible for MTBI?
Is the brain a delicate, jello or custard like substance?
Are the frontal lobes referred to as the "dashboard of the brain" because of their susceptibility to injury due to the sharp bony ridges underneath the frontal lobes? (see article by Varney and Menefee, 1993)
Is it necessary to strike your head to sustain a MTBI?
What is "shaken baby syndrome?"
What is the significance of a Glasgow Coma Scale (GCS) score of 13-15? (Note: it was never intended by the originator of the scale (Dr. Brian Jennett) to be used in MTBI cases)
What is the significance of post traumatic amnesia (PTA)? Does amnesia indicate diffuse brain damage? (see Jennett article)
Can an acceleration/deceleration or whiplash type injury produce a MTBI? ( see articles by Gennarelli, Ommaya, Jane, Oppenheimer, and Lezak)
What are the differences between a diffuse and focal brain injury?
Can a focal injury or contusion to the brain occur without loss of consciousness? (e.g., Phineas Gage)
What is diffuse axonal injury (DAI)?
What is a concussion? Is the brain damaged in a concussion?
What is the effect of repeated concussive injuries? (Lezak, Gronwall, Kelly. See article "Brett Lindross ends career: concussion-prone Islander heeds brain damage warning" in The Globe and Mail, May 2, 1996)
Would you expect MTBI patients to have normal results on a neurological exam, CT scan, MRI, or EEG?
Is neuropsychological testing more sensitive to MTBI?
What tests are sensitive to MTBI? Did expert administer those tests? (Kay, 1992)
What pattern of test results suggest MTBI?
Is it appropriate to use the MMPI in MTBI cases?
What is the significance of collateral information from family, friends and co-workers as to changes noticed in a person who has sustained a MTBI?
Is it important to utilize all the information from collateral witnesses before forming an opinion as to MTBI? Did defence expert have this information or were inquiries made? (Varney and Menefee,1993)
What are the common symptoms associated with MTBI? (See definition in JHTR. Physical symptoms include: nausea, vomiting, dizziness, headache, blurred vision, quickness to fatigue, lethargy. Cognitive deficits include attention, concentration, memory, speech/language, or executive functions. Behavioural changes and/or alterations in degree of emotional responsivity include irritability, quickness to anger, disinhibition, or emotional liability)
Did plaintiff suffer from these problems before the accident?
Did expert inquire how these problems affected plaintiff's life?
Assuming a diagnosis of MTBI, what is the usual recovery period?
Do a significant minority of persons never recover?
Is it true that the longer the symptoms have lasted the more likely they will be resistant to treatment?
- Is there any treatment recommended for MTBI?
Cross-Examination of a Defense Physiatrist in a MTBI Case
T------ (for Defendants) Cross?exam by Mr. Slater
- Q Thank you. Doctor, in arriving at a diagnosis of a traumatic brain injury you are going to want a history from the patient obviously, correct?
A Yes. Q You are going to want to look at all the available medical information, right? A Correct. Q You are also going to want to look at the results of neuropsychological testing, if it is available? A It can be very important, yes. Q Right. You agree that you refer people for neuropsychological testing? A That's correct. Q And that's because the insensitivity of the neurological examination and the mental status examination, correct? A They will play a role in terms of what information they are going to give you. So there is different information obtained from different aspects of what you look for. So neuropsychological will give you different information to your history, to your physical exam. Q But the reason neuropsychological testing developed the way it has is because the insensitivity of the neurological examination (inaudible); isn't that correct? A Yes, gives you a more detailed assessment of the patient's ?? functioning at that point in time. Q You would want to see the results of neuro?diagnostic testing, if any? A It can be very helpful, yes. Q And you would also want to independently verify circumstances surrounding the motor vehicle accident to test whether or not the history received from the patient was accurate, correct? A Yes, that's helpful. Q And you would also want, if you had the opportunity, to interview persons close to the person that you are examining. For example, spouses, employers, co?workers, you would want to obtain as much information as you could get from credible, reliable people, correct? A That's correct. Q And the reason you are looking for that is you are looking for changes that occurred after a particular event that would assist you in determining whether or not the traumatic event was significant in terms of behavioral changes, emotional changes physical changes, cognitive changes, correct? A Correct. Q And if that evidence is reliable and credible that there was a significant change in an individual's functioning in those areas that would be of some assistance to you in [assessing] the rest of the information gathered to determine whether or not there was a mild traumatic brain injury? A You have to [look] not just for traumatic brain injury, but for any other diagnosis that may be warranted. Q One of the problems that you have, I would suggest, doctor, speaking generally, in arriving at a diagnosis of mild traumatic brain injury is that only in the rarest of cases will you ever have any direct information about what the person looked like prior to the accident, what they ?? how they performed in terms of an actual image of the individual; you don't have that, do you? A No. Q Now, doctor, you would also agree that in order to follow a definition of mild traumatic brain injury if we have either a dazed situation or a situation involving some PTA it can't be more than thirty minutes loss of consciousness, if we are talking loss of consciousness, or it can't be less than a Glasgow Coma Scale of thirteen or fifteen and it can't have PTA more than twenty?four hours? A That's correct. Q So what they are doing is that they are excluding all those categories because they are moderate or severe traumatic brain injury, correct? A That's correct. Q Now, under the comments, the comments aren't required for the definition. They are just to give you some background information and understand how the definition applies; isn't that right? A That's correct. Q So you would agree with me that when they go onto say that the definition includes under three; the brain undergoing an acceleration/deceleration movement, i.e. whiplash without direct external trauma to the head; you would agree with that? A Yeah, any type of trauma that involves the brain and the head which travel at different speeds and because they travel at different speeds that can induce injury to the brain. Q What you are talking about here in these types of injuries is you are talking about different densities in the brain, for example, the white and the gray matter? A That's correct. Q And you are talking [about] in particular if there is a rotational component like you have in an accident where a car is whipping around the different densities of the brain are moving at different speeds? A That's correct. Q And what you are getting is shearing or tearing of axons in the brain; are you not? A It is a theoretical concept. We haven't actually proved that, but that's what we believe at this point in time. Q Well, you have done reading in the area; haven't you, doctor? A I believe that at this point of time. Q You are familiar with the work of Oppenheimer (phonetic)? A No. Q Are you aware of work of Omaya (phonetic) and Oppenheimer and Gennarelli (phonetic); are you aware of situations where people have actually examined brains of people who have sustained concussions? A Yeah. Q And they have died for other reasons, they have examined the brain and there it is, shearing and tearing of axons? A That's been shown in animal models. Q Would you agree that it is generally regarded as accepted in the field of traumatic - mild traumatic brain injury that the mechanism of the injury is the shearing and stretching of axons hence the diffuse axonal injury? A Yeah, I believe that. Q Now, doctor, would you agree with me that - and you know who Thomas Gennarelli is? A Yes. Q He is the one that did all the research with the monkeys, correct? A Yes. Q They took those monkeys and they subjected them to known forces of acceleration/deceleration, killed them and examined their brains? A True. Q So they were getting a whiplash type of concussive injury, correct? A True. Q And they found a [diffuse axonal] injury; correct; is that right? A Yes. Q Now, Gennarelli, you would agree with me, says that a hit on the head, in this type of injury ? the only significance of a hit in the head is the extent to which you create the acceleration/deceleration forces? A That's correct. Q And it's the acceleration/deceleration which is more important than the hit on the head? A Yeah, because with the hit in the head it's a sudden deceleration. It is the same thing and it is a sudden change in speed. Q Without getting into physics in any detail, if you have a motor vehicle accident where there is a rotational component in the sense of a vehicle being spun sideways and then a double contact, that's what we are talking about here in terms of motor vehicle accidents, whiplash head injuries, in general sense, correct? A Yes. Q So then it becomes an assessment of what happened to the person after the accident, what do they recall, bringing your expertise into consideration, looking at neuropsych evidence, looking at the collateral evidence before and afterwards, that's the process of a diagnosis of a mild traumatic brain injury, correct? A That's correct. Q You didn't have any collateral information other than what you told me, correct? A That's correct. Q You didn't have any neuropsychological evidence; did you? A No, I didn't. Q Now, doctor, you are aware of, I take it, a book called Mild Head Injuries by Levin (phonetic); are you not? A Yes. Q That ? probably came along in a time when he was recognized as a authority in the field? A That's correct. Q And this is the textbook you are familiar with; is that correct? A Yes. Q And there is a chapter in there by Gronwall (phonetic); is it not, doctor? A I think so, but I would have to check. Q I'll find it for you on this issue of distractibility. I won't ask you if you agree ? you see here ? and I'll find it in my copy. Cumulative and persisting effects of a concussion on attention and cognition by Dorothy Groomwall. Do you see that? A Yes. Q Turn to page 153, Doctor. Well, Doctor, for the moment, I do have a copy somewhere, I'm going to ask you to read ? I've got page 154 here and it's under the heading, Effective Reduced Processing Capacity on Function After MHI; do you see that? A Yeah. Q And the second paragraph. Would you agree that part of this problem with the executive functioning in mild traumatic brain injury cases and distractibility is that their ability to process information is somehow impaired. A Yes. Q And they don't process information as quickly, as accurately as they did prior to the traumatic event, correct? A That's true. Q Could you read that paragraph that I referred your attention to? A After MHI patients have difficulty in all areas that require them to analyze more items of information than they can handle simultaneously. They present as slow ? because it takes longer for smaller than normal chunks of information to be processed. They present as distractible because they do not have the spare capacity to monitor irrelevant stimuli at the same time as they are attending to the relevant stimulus. They present as forgetful because while they are concentrating on point A they do not have the processing space to think about point B simultaneously. They present as inattentive because when the amount of information that they are given exceeds their capacities and they cannot take it all in. Q Do you agree with that? A Oh, yeah. Q And that's really the definition of mild traumatic brain injury and why some of these people are called the walking wounded. A Yes. Q Because they look normal, correct? A Physically they do. Q And they function? A That's correct. Q But is the issue, from your perspective, doctor, as an expert in this field the quality of how they function now relative to how they functioned before? A Yeah, if it made any difference in subtle things that prevent them from doing their job. For example, you may have somebody who is an academic ? very bright and doing very high level things, it just ? the edge and you cannot compete in that capacity anymore. They may still score highly on those tests and look completely normal. Q Doctor, can I try and use an analogy? A Sure. Q And see whether or not that provides some assistance in understanding this. Doctor, do you use computers? A Yes. Q And do you use a Pentium computer? A I do. Q And do you do some of the typing on your own? A I hate it, yes, but I do. Q And you actually start to think with the computer, don't you, after a while? A Yeah. Q And you construct your thoughts and put your information together and you can move it around on the screen and it is much different than pencil and paper, correct? A That's right. Q Now, I take it that you don't know much about what is going on inside that machine? A Not really. Q Okay. Now, if I come in, in the middle of the night and I take out your co-processor and put in a 486 you wouldn't know that and you would start working on your machine; wouldn't you? A Yeah. Q And it would work, but it wouldn't work as fast, would it? A That's correct. Q And it might not handle some of the software that you were running on a Pentium very well, correct? A It probably wouldn't. Q It might have a problem interacting with the printer; is that right? A It likely would. Q And it might crash on occasion? A Yes. Q Now, if nobody told you that someone had changed your co-processor wouldn't you start to feel a little bit like what is wrong, what is going on here; wouldn't you start to think about that? A I certainly would. Q And couldn't you eventually develop some sort of psychological reaction and start to doubt yourself and find that your whole sense of who you are and what you are is being affected because you are not getting information out the same way? A Yeah. Q And if you've got a boss over your shoulder and that boss has come to you and says, where is that medical report, where is that report that you were supposed to prepare, you tell him that well, I'm trying, but it's really not me. The computer is not working right. You would get frustrated; wouldn't you? A Uh?huh. Q And over time you get more and more frustrated; isn't that right? A You would. Q And if I suggested to you that I'm not going to ever replace the  you don't know that you don't have it in there, but if you never ever get your Pentium back and you are stuck with that 486 you can function, but you don't function that well, correct? A That's correct. Q And if everyone else is moving up to Pentium III's and then eventually beyond and you are stuck with that 486, you are going to continue to fall behind other people; isn't that right? A Definitely. Q And if I was to tell you two weeks later, as you are exasperated trying to interact with this computer that hey, it's really not you, it's the chip inside the computer, you would have a sense of relief; wouldn't you? A I probably would. Q And if there is any way I can fix that, give you your old co-processor back, you could function well; isn't that right? A I probably would. Q Is that a reasonable analogy for what happens in mild traumatic brain injury? A Yes. Q And would you agree with me that the jury is out on whether or not cognitive rehabilitation or any form of rehabilitation is really going to assist a person in dealing with all the problems associated with mild traumatic brain injury? A ?? Rehabilitation ?? in the early 90's was - it hasn't really been that useful?? there are more useful means of treating these patients now - as day to day events and daily living skills. Q And, Doctor, do you agree that when the average individual sustains a mild traumatic brain injury, that there can be a lot of ignorance out there in the medical profession about the effects of mild traumatic brain injury? A There definitely is. Q In terms of diagnoses of the injury? A Yes. Q In terms of being skeptical about whether the symptoms are real symptoms or just a figment of someone's imagination? A Absolutely. Q They are accused of malingering? A Absolutely. Q They are accused of exaggerating? A Yeah. Q And they are accused in cases of litigation very often as seeking compensation for injuries not legitimate, correct? A I won't comment on that, but I think that these patients have a tough time. Q And the more sophisticated the expert who comes in contact with these individuals, the better the likelihood that they'll figure out what is wrong with them and hopefully relieve the psychological pressure that builds up? A That's true. Q And would you also agree with me that in relation to a traumatic injury, speaking generally, that you can have a reactive depression or a depression directly related?to the, brain injury? A That's correct. Q And it can be very difficult sorting out the two? A You may not be able to, yeah. Q You can treat the reactive depression, correct? A You may. Q But you can't treat an organic - depression related to a brain injury? A Well, you have to try to get some improvement with medication, but you may not treat it completely. Q Well, it's difficult to treat it, correct, and that's because any injury to the brain, any damage to the brain and we are talking injury and damage, that's the same thing, correct? A Yes. Q That damage is irreversible; isn't that right?
A Hopefully in the next ten or twenty years we will have more information, but at this point it is considered to be irreversible, yes.
1  2 S.C.R. 24 at 42.
2 Sopinka, J., Lederman, S.N., and Bryant, A.W. The Law of Evidence in Canada, Butterworths, 1992 at 534.
3 1993] Lloyds Rep 68. , S.C.R. 672 at 684.
4  O.J. No. 2199 (Ontario Court of Justice - General Division)
5 Iannuzzi, J.N. Cross-Examination: The Mosaic Art, Prentice-Hall, Inc., 1982 at 216.
6 Schwartz, L. E. Proof, Persuasion, and Cross-Examination: A Winning New Approach in the Courtroom
7 Executive Reports Corporation, 1978 at 2103.
8 (1995), 11 B.C.L.R. (3d) 1 (B.C.S.C.) at 78.
9 Ibid., at 79.
10 Supra, n. 3 at 560.
11 (1914), 22 C.C.C. 455 at 476, 7 Alta. L.R. 102, 5 W.W.R. 1052, 26 W.L.R. 783, 16 D.L.R. 203 (C.A.).
12 Supra, n. 6 at 75.
13 C.E.D. (3rd), at 379-380.
14 Supra, n. 3 at 560-563.
15 Supra, n. 6 at 75-79.
16 Supra, n. 3 at 561-562.
17 Supra, n. 6 at 77.
18 References to articles can be found in prior editions of The Verdict. See Mild Traumatic Brain Injury: An Introduction, December, 1994; Traumatic Brain Injury (TBI) Without Loss of Concsiousness (LOC), January, 1996; Mild Traumatic Brain Injury (MTBI) and the Thin Skull Rule, March, 1996.