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Tag: engineering evidence

The Shortcomings of "Occupant Dynamics" Expert Evidence


Accident reconstrucion experts routinely give evidence during BC personal injury lawsuits when fault for a motor vehicle crash is at issue.  One subset of such expert evidence is “occupant dynamic” evidence which seeks to explain how a passenger would be thrown around following a collision.  While this evidence can have some value at trial it is accompanied with certain shortcomings.  These were discussed in reasons for judgement released this week by the BC Supreme Court, Vancouver Registry.
In this week’s case (Byer v. Mills) the Plaintiff was one of two occupants in a vehicle which was involved in an at-fault collision.  The central issue at trial was who the driver of the vehicle was.  The Plaintiff was badly injured and had no recollection of who was driving.  The second occupant of the vehicle died shortly following the crash.  There were no independent witnesses addressing who was driving at the time of the crash and the Court had to decide this issue relying on circumstantial evidence.
In the course of the trial the Court heard evidence from an ‘occupant dynamic‘ expert.   Ultimatley Mr. Justice Harris dismissed the Plaintiff’s lawsuit finding that, on a balance of probabilities, he was likely the driver therefore he was at fault for his own injuries.  This decision was most influenced by lay witness evidence and the occupant dynamic expert testimony was of little value in this particular case.  Mr. Justice Harris provided the following short but useful comment addressing the shortcomings of occupant dynamic evidence:
[54] The principles of occupant dynamics are helpful up to a point. Certainly, they assist in identifying the principal direction of force exerted on occupants. They are also helpful in identifying the point at which an occupant might be expected to make initial contact with the interior of the passenger compartment. In my view, in the circumstances of this collision, the predictive value of principles of occupant dynamics rapidly diminishes once the movement of the passengers is affected by contact with the interior of the compartment and with each other. At that point the situation becomes inherently dynamic and fluid. There are far too many variables involved to make accurate predictions of how the occupants and parts of their bodies would move once they start hitting each other. It must be remembered that if unrestrained an occupant would be traveling within the compartment at a speed of about 55 km/h. I am sceptical that any reliable prediction of how the occupants would interact with each other, with the interior of the passenger compartment and move within it can be undertaken.

More on Out of Court Statements and Their Use at Trial in ICBC Injury Claims


Further to my two recent articles discussing this topic (these can be found here and here) reasons for judgement were released today by the BC Supreme Court, Kelowna Registry, demonstrating yet again the powerful impact out of court statements can have in an ICBC claim.
In today’s case (Aymont v. Capp) the Plaintiff sustained serious injuries in a 2004 BC motor vehicle collision.  She was driving a Mazda Protege and was exiting a gas station parking lot.  She intended on turning left.  As she entered the roadway the Defendant approached from her left hand side.  A ‘t-bone’ type of collision occurred.
The Plaintiff testified at trial that when the Defendant’s vehicle struck hers she was at a stop and her vehicle had not entered the roadway and was “two feet before the fog line“.  The Defendant disagreed and testified that as he approached the gas station the Plaintiff pulled her vehicle into his lane of travel leaving inadequate time to avoid the collision.
During trial the Plaintiff was confronted with various out of Court statements attributed to her where she discussed the collision.  These included statements given to ICBC, a police officer and a chiropractor.  These previous statements were summarized as follows by Madam Justice Gropper:

[9]             The day following the accident, May 15, 2004, Ms. Aymont went for treatment to her chiropractor’s office, Dr. Susan Holroyd.  She says that she felt dizzy and nauseous, disoriented and in a great deal of pain that morning.

[10]         Dr. Holroyd produced her clinical records, which included a “motor vehicle accident history” form.  Ms. Aymont says that she does not recall the form or filling it out.  She cannot recall if it is her handwriting on the form or not.  The handwritten notations (in italics)  on the form state, in relation to the accident:

State How Accident Happened in your own words.

I had stopped at the entrance of gas st. looked both ways saw no one and began onto road – was hit by a truck travelling very fast.

Where you stopped Yes/No?

No [circled]

Estimate your speed?

10 km/h

Brakes on Yes/No?

No [circled]…

[13]         Cst. Rudy Andreucci telephoned Ms. Aymont the day following the accident and they arranged to meet on Sunday, May 16, 2004 at the RCMP Detachment in Westbank.  Cst. Andreucci testified that the purpose of the meeting was to give Ms. Aymont a traffic violation ticket. Cst. Andreucci served a violation ticket on Ms. Aymont for a breach of s. 176(2) of the Motor Vehicle Act: emerging vehicle: failure to yield.  He noted on the reverse side of the ticket what Ms. Aymont said to him:

04-5-16 V.T issued at office dri Nancy Aymont advised she just didn’t see him.  She knows better-than go on without being sure….

[15]         On May 21, 2004, Ms. Aymont met with Mr. Bonner of the Insurance Corporation of British Columbia (“ICBC”) at his office.  Mr. Bonner is a bodily injury adjuster.  He was the adjuster assigned to Ms. Aymont’s file.  Another adjuster was assigned to Mr. Capp’s file.  Mr. Bonner said that he asked questions and typed the answers into the ICBC note taking system on his computer.  He prepared a sketch based on the information provided to him by Ms. Aymont.  In the statement Mr. Bonner recorded Ms. Aymont stating:

I looked to my right first, and then the left and Bartley Road was vacant, and I thought to myself how often does that happen on a Friday afternoon.  After looking right, then left, I looked right again, and that is the last thing I remember…  If the other driver wasn’t going so fast he probably could have stopped.  My husband drove the road the next day.  At the 50 km/h speed limit, and stopped without skidding before the driveway… I was knocked out and can’t say how far I pulled forward from the exit onto Bartley Road before being hit.

[16]         Ms. Aymont also provided a rough sketch showing where the vehicles were as she approached the exit.

[17]         Ms. Aymont does not recall saying “I can’t say how far I pulled out from the exit onto Bartley before being hit.”

[18]         Mr. Bonner produced a hard copy of the statement for Ms. Aymont to review.  She thought that the second page statement was “all mixed up.”  Ms. Aymont says she made certain corrections to the statement in handwriting.  The last sentence of the statement is “I have nothing to add to this statement, which is true to the best of my memory.”  Ms. Aymont signed the statement….

The Court ultimately rejected the Plaintiff’s evidence and accepted the Defendant’s.  This verdict was largely reached based on the Plaintiff’s prior statements.  Madam Justice Gropper gave the following useful reasons demonstrating the damage that can be done with ‘prior inconsistent statements‘:

[77]         Mr. Capp’s evidence that the Aymont vehicle was moving when he first observed it is consistent with the statements that Ms. Aymont made to her chiropractor.  In the form that she completed, or directed Dr. Holroyd to complete, she says that she was not stopped and was moving at about 10 km/hour.  In her statement to Cst. Andreucci she stated that she just did not see Mr. Capp’s vehicle.  She told Mr. Bonner that she had pulled forward from the exit onto Bartley Road before being hit.  All of these statements are consistent with the circumstances that Mr. Capp describes.

[78]         I find as a fact that Ms. Aymont was not stopped “well before the fog line”.  She was moving from the exit into the southbound lane of travel on Bartley Road.  She was going slowly, likely less than 10 km/hour.  Her foot was not on the brake.  She was not looking in the direction of the oncoming traffic, but was engaged in a conversation with her son Joel who was sitting in the passenger seat, and had turned her face toward him to talk about his drink.

[79]          Ms. Aymont did not yield the right of way to Mr. Capp who was the dominant driver. …

[82] In all of the circumstances, I find the plaintiff is 100% at fault for this accident.

This case is also worth reviewing for the Court’s discussion of the duties of expert witnesses.  Both the Plaintiff and the Defendant retained experts to give accident reconstruction evidence.  The Plaintiff’s expert was soundly criticized for giving evidence as an “advocate” instead of a neutral witness.  The criticism can be found at paragraphs 66-73.

Expert Evidence and Litigation Privilege

It is common for lawyers involved in personal injury claims to retain the services of expert witnesses.  The most common expert witnesses are medical doctors but often engineers, economists, and other specialists are brought into the fray.
Experts are typically retained to be involved in two common roles.  The first role is to provide expert opinions to assist the judge or jury to understand the evidence called at trial.  The second is to assist counsel in preparing the case for trial.  When experts are retained to assist counsel to prepare for trial the communications between the expert and the lawyer are confidential and subject to litigation privilege.
When an expert takes the stand and gives opinion evidence they are subject to a cross-examination that is quite wide in scope.  Does this permit the opposing side to ask questions about the confidential opinions and advice the expert gave the lawyer that retained him prior to trial?  Not necessarily.  Reasons for judgement were transcribed today by the BC Supreme Court, Vancouver Registry, dealing with this issue.
In today’s case (McLaren v. Rice) the Defendants to a car accident claim hired an engineer who was qualified to give expert opinion evidence regarding accident reconstruction and speed and speed changes.  During cross examination the lawyer for the Plaintiff asked whether the defence lawyer sought his opinion with respect to a vehicle’s tie-rod and ball-joint assembly.  The Defence lawyer objected to the question claiming it addressed matters that were protected by litigation privilege.  Mr. Justice Brooke upheld the objection and in doing so summarized and applied the law as follows:

[4] In the recent decision of Madam Justice Satanove in Lax Kw’alaams, 2007 BCSC 909, the nature and extent of litigation privilege was considered.  At paragraph 9, Justice Satanove referred to the decision in Delgamuukw where it was said that litigation privilege was waived when the expert witness was called, but that that waiver was to be narrowly construed and privilege maintained when it was fair to do so.

[5] In Vancouver Community College v. Phillips, Barratt (1987), 20 B.C.L.R. (2d) at 289 (S.C.), Justice Finch, as he then was, recognized that even where an expert is called as a witness he may remain a confidential advisor to the party who called him at least in regard to advising on cross-examination of the other side’s witnesses, including the other side’s expert witnesses.

[6] In Lax Kw’alaams as well as in Barratt, the issue was the production and cross-examination on documents that had been prepared by the witness.  As I understand it, here all privileged documents are set out in part 3 of the document disclosure of the defendant and there is no suggestion that there are undisclosed documents.

[7] What the plaintiff wishes to cross-examine upon is not documents, but oral advice or opinions or commentary concerning the tie-rod assembly and ball joint, an area which the report of Mr. Brown does not pretend to address.

[8] I find, if Mr. Brown was asked questions out of court regarding the tie-rod and ball-joint assembly it was to assist the defendant in its defence of the plaintiff’s claim and specifically the allegation that the collapse of the tie-rod and ball-joint assembly caused the accident in which the plaintiff sustained devastating injuries.

[9] In my opinion, it would not be fair to require Mr. Brown to answer questions directed to matters outside the scope of his report because it could give the plaintiff an advantage not available to the defendant.  Here I refer to paragraph 29 of Barratt.  Moreover, to permit such cross-examination would cast a chill over the ability of counsel for both plaintiffs and defendants to properly prepare their client’s case and also to answer the other party’s case.  In the result, the objection of the defendant is sustained.