Expert reports in comp claims: tips to avoid evidentiary traps P1
2nd Nov 2016
It is trite that the factual assumptions that underpin an expert’s report must be proven or otherwise accepted by the court in order for to allow the opinions of the expert to be scrutinised by way of objection or weight, and to stand a chance of being accepted by the court.
The same principle applies whether the expert is deployed as the sole expert engaged on the issue, or as an expert for either claimant or respondent. In compensation claims, this commonly presents itself in the context of medical opinions of the nature and extent of the claimant’s injuries.
There are many cases where the factual background to the claimant’s medical specialist’s opinions is undermined by objective evidence shown to contradict the claimant’s version of events. For example, by way of video evidence or, as so often occurs these days, by information posted on social media accounts.
Undermining the factual basis upon which the expert bases their opinion is one of the key elements of successful cross-examination, and if undertaken well, can lead to significant fluctuations on the prospects or the quantum of the claim, or both.
In the preparation of cases either before compulsory conferences, or after, this issue is sometimes overlooked by the parties. This article highlights tips which will assist practitioners’ in ensuring their expert opinions carry the most weight.
What facts and assumptions does the expert need to consider?
The gathering of facts should not be left solely to the expert. They should form part of the instructing letter, but before doing so ensure the facts are properly tested, where possible, against objective evidence. An accurate record of the factual background which has given rise to the creation of the cause of action is vitally important. Not only does that inform the opinion of the experts, but it also must inform the decision of whether the matter has any prospects of success. Without an accurate, and detailed, examination of that factual background, there is scope for error or overreach. Avoiding error and overreach leads to the best chance of settling a claim at an early stage, but if that is not possible, then an accurate record be invaluable at trial, and it will significantly enhance the prospects of a good outcome.
In order to be accurate, it is important to test everything (of relevance) the client and witnesses tells you to determine areas of inconsistency, or any matter that seems contrary to common sense. How you go about testing the information you are given or that is obtained is different depending on the type of information.
To take a simple example, if the client informs you that the accident happened at 10am on Tuesday, 2 August 2016 while at the premises of the client’s employer, while undertaking a task in the course of employment, then this information should be cross-checked with the workers’ compensation claim forms, any medical certificate, any incident report, any report from a Workplace Health and Safety inspection, available witnesses and the employers time and wage records if necessary in the case of any doubt that the claimant was actually undertaking that work on that day.
Another example is the claimant’s complaint that the injury causes certain symptoms which restricts their ability to undertake a particular activity. Often the complaint of restriction needs to be particularised in greater detail in order to identify just what ‘restricted’ means. Can the action be performed at all? If so, when, where and what are the circumstances where it can and cannot be performed? Be careful to avoid overstating the clients’ difficulties in instructions to experts, even if the client is adamant. Remember that each party often obtains the other’s instructions to experts in the disclosure process.
When briefing the expert, set out the factual background as best you can by reference to objectively ascertained and contemporaneous documents. For instance, if the incident involved a motor vehicle collision, the speed might be relevant to the extent of the claimant’s injuries. There may be notes from the investigating police officer of what witnesses said of the speed, but do not rely solely on those notes. Call the witness if possible to confirm those notes. Often contacting witnesses reveals matters of relevance that the officer may not have noted, like a comment made by the defendant at the scene, or the behaviour of the claimant. There may be a report from the police which assesses the speed using the skid marks and point of impact. If a medical expert is engaged to opine the full nature and extent of the injuries complained of by the claimant, speed may be relevant to the extent of the symptoms displayed. For example, it may be relevant to an orthopaedic surgeon when examining a person complaining of severe back pain with radiation down the lower limbs that the incident involved a low impact rear-end collision at a speed of no more than walking pace.
But then it may not be that relevant either. I recall the matter of Ranger v Suncorp[ET1] (the issue involving interrogatories is cited at  2 Qd R 433) in which I acted as solicitor for the plaintiff. The incident was a relatively low-speed impact where the plaintiff was wedged between a slowly reversing car and a petrol bowser, but sadly the plaintiff nevertheless suffered significant injuries. It was an unusual case. The defendant denied any impact occurred at all and wanted to interrogate the plaintiff. However, both the Supreme Court and the Court of Appeal would not let them. It was important in the prosecution of the case to be sure of the mechanism of the incident and to be sure that the complaints of significant injury and pain were properly tested as the expert opinion depended heavily on them being accepted. The matter settled, but the case shows the importance of ensuring that the evidence the claimant intends to give, or would give if the matter proceeds to a trial, is tested against any available objective criteria.
Engineering expert reports are no different. Identifying the precise mechanism of the injury cannot be overstated. Recently, in Valentine v D & C Masters Painters & Decorators PL  QDC 203 (Valentine’s case), the plaintiff’s claim was unsuccessful because the court was not satisfied that the door mat on which the plaintiff slipped posed a foreseeable risk of injury. Expert engineering evidence was obtained. Unfortunately, the actual mat was not available for evidence, and the plaintiff did not recall what type of backing it had. But he did know it was on a wooden floor when he slipped on it. The plaintiff was an experienced painter, and he had been engaged over the prior few days painting a residential premises owned by the State. The plaintiff had walked over the mat each day he had attended the premises without issue, until he slipped on the day of the incident.
The first opinion of the engineering expert was not based on any inspection of the premises, or any information given by the occupant. It was based solely on the plaintiff’s perception of the type of mat he slipped on. This perception was portrayed in photographs the plaintiff took of some mats he found at Bunnings he thought looked like the mats ‘as being as close as (he) could recall’(at ). The expert purchased two mats which he thought were similar to the ones in the photographs and tested them. The trouble was, they had fabric or sisal backing.
The occupant had been in the premises for 26 years, and her unchallenged evidence was that she always had rubber backed mats and in all her time living there no-one to her knowledge had slipped on the front door mat including children.
The trial judge considered there was merit in the objection taken by counsel for the employer to the expert opinion as having little or no probative value because it was based on the fabric and sisal mats. Nevertheless, the opinion set out the relevant Australian Standards and interpreted dry floor friction results with a note that a coefficient of friction (COF) value at equal to or less than 0.40 would have a moderate to very low contribution to the risk of slipping when dry.
At a later inspection at the property, the floor was tested, as was the rubber backed mat, with result that produced a COF of 0.36. The judge assessed the risk of slipping as “moderate to very low”. In cross-examination, the expert conceded that a rubber backed mat would be recommended and present a much lower slip risk than a sisal or fabric backed mat.
This case shows the importance of ensuring the expert is given an accurate account of the factual background. If the plaintiff cannot recall, then investigations may reveal the truth from other sources. In Valentine’s case, the judge commented, at , that if the plaintiff had noticed the mat, and if he asked the tenant if it was a risk, he would have been told that for two decades no-one had slipped on the mat. The tenant may well have given detailed evidence about the type of mat, and the expert would then have had the best information available to provide the best evidence in the form of an opinion able to be relied upon as being based on established background facts.
Check next week’s edition of ALAn for part two of Ben Whitten’s article and find out how to choose the right expertise and ask the right questions.
Benjamin Whitten is a barrister who practises in commercial, equity and insurance litigation. He has a particular interest in claims involving construction & engineering issues and failures.
The views and opinions expressed in these articles are the authors' and do not necessarily represent the views and opinions of the Australian Lawyers Alliance (ALA).