In our latest article, Expert Witness Institute (EWI) governor and MAPS trustee, Peter Mulhern, discusses and summarises key points from a recent EWI webinar which analysed how expert witnesses assist the court in assessing damages in cases where the accident or other event or process has not clearly caused the claimant’s injury due to a pre-existing condition.
During the webinar, three experienced expert witnesses and an experienced barrister discussed the legal and medical/scientific context of this type of claim, explored case examples and offered key advice on best practice for writing reliable and helpful medico-legal reports.
The panel
Mr Abeezar Sarela – a consultant general surgeon specialising in upper GI and hernia surgery, with a particular interest in laparoscopic surgery. Mr Sarela has been writing reports since 2011 and provides Part 35 reports in both personal injury (PI) and clinical negligence (CN) cases and accepts instructions from both claimants and defendants.
Mr Ajit Ambekar – a semi-retired consultant orthopaedic and trauma surgeon with extensive clinical experience in major trauma, multiple injuries, spinal surgery, knee surgery and hip surgery. Mr Ambekar has significant medico-legal experience in the UK, Europe, Cayman Islands, USA and Canada, focusing on major trauma/multiple injury cases and injuries abroad, writing reports for both claimants and defendants.
Dr Kathryn Newns – a clinical psychologist with particular interests in trauma, phobias, anxiety and pain conditions. Dr Newns has prepared medico-legal reports since 2008 across PI, CN, Criminal Injuries Compensation Authority (CICA), Employment Tribunal (ET) and mental capacity cases. She holds a master’s degree in pain management approaches and reports on both adults and children.
Dr Louise Sherlock – a barrister dual-qualified in dentistry and law. Before joining No 5 Barristers’ Chambers, she practised as a dental surgeon for more than 10 years.
Dr Sherlock – specialises in CN work but also has experience in PI, inquests and public inquiries. She has recently published a book on dental negligence litigation and frequently cross-examines expert witnesses as part of their assessment with the EWI.
The medico-legal context
Dr Sherlock set the scene, reminding delegates that the aim of awarding damages in a tort claim is to restore the claimant to the position they would have been in “but for” the accident.
Applying the “but for” test can be challenging when the claimant has a pre-existing condition that may or may not have been causing symptoms immediately before the accident, event or process. Lawyers rely on expert witnesses to provide evidence to assess damages, clarifying if the accident has caused the injury or symptoms in whole or part, or in some cases if it has made a “material contribution” to the injury.
The experts
Working from the broadly agreed starting point that there is no clear-cut scientific method by which to assess acceleration and/or exacerbation, the experts gave some examples from their specialisms.
Mr Sarela noted that as a medical expert witness, he assesses evidence based on the balance of probability. He used the example of a hernia case to draw a contrast between the clinical and medico-legal approaches. In a clinical sense, he offered the opinion that no single event is likely to cause a hernia outright. All, or almost all hernias arise as a result of a pre-existing weakness, which in a medico-legal context is accelerated by an accident or event to cause symptoms, on the balance of probability.
Mr Sarela confirmed that, in his opinion, a prolonged and/or repeated process of heavy work might, in some circumstances, be capable of causing a hernia.
Mr Ambekar talked about the situation in which a claimant has suffered multiple injuries or major trauma. He emphasised that the expert would need to take great care to identify the factors that would support their opinion as to any exacerbation or acceleration.
Mr Ambekar also noted that, in some cases, the orthopaedic expert witness will need to discuss evidence that leads to their advising that an expert witness, from a different specialism, ought to be instructed in the case. Often this situation arises when the orthopaedic expert is unable to provide a physiological explanation for the duration and/or level of the claimant’s symptoms. Mr Ambekar described this type of case as involving “functional impairment”. In this situation, the orthopaedic expert witness would potentially recommend the instruction of an expert witness in pain management, psychiatry or psychology.
One particular point of interest was the discussion of the difference in outcomes for a claimant between the gradual onset of symptoms from a pre-existing condition “in the normal course of events” and the sudden onset of symptoms resulting from an accident or event.
This point was further examined by Dr Newns, who provided insights into the concepts of exacerbation and acceleration from a psychological perspective. Dr Newns emphasised the importance of thorough history-taking in the field of psychology. The psychology expert witness is interested in identifying the sequence of events that has resulted in the claimant’s current condition. Detailed and precise history-taking is crucial, as individuals typically do not compartmentalise their emotions.
From a pain perspective, the psychology expert witness will pay particular attention if the orthopaedic/physiological expert witness is offering the opinion that the claimant’s physical symptoms have been accelerated by the accident or event. For instance, if a claimant has a condition like osteoarthritis, which would eventually cause pain, the psychologist may offer an opinion on how, in the absence of the accident, the claimant might have managed the gradual onset of symptoms through treatment and lifestyle adjustments compared to their response to the sudden onset of symptoms following an accident or event.
Practical points
The experts then discussed with the barrister, Dr Sherlock, how skilled expert witness will attempt to assist the court in the way they structure their report and offer their opinion. Expert witnesses need to understand the “but for” test and to use the established language of the courts when offering their opinion.
Everyone agreed that a good medico-legal report dealing with the concepts of exacerbation and/or acceleration would always have a clear focus on a number of key points:
- The history of the accident or event, as described by the claimant;
- The description of the accident or event, from the claimant and any other relevant sources, particularly in terms of the information available about the mechanics of the accident and the forces involved;
- The history of the event or accident, from the medical records, with reference to contemporaneous and subsequent treatment;
- The previous medical history, including imaging and other tests where appropriate;
- In cases without a physiological explanation for the claimant’s symptoms, the evidence supporting the expert’s opinion and any recommendations the expert witness makes, particularly regarding the involvement of other expert witnesses from different specialisms;
- The expert witness may consider citing relevant medical literature in support of their opinion. While it’s generally preferable not to reference an excessive number of sources, where relevant literature exists, concise citations from it can be useful. Dr Sherlock noted that, from the lawyer’s perspective, it’s essential to cite relevant sources concisely; otherwise, there’s a risk that the opposing expert witness does cite unopposed authorities, potentially influencing the judge’s decision.
The experts and the barrister also mentioned the need for the expert witness to remember their duty under CPR Part 35 PD 3.2 (6) to identify and comment on any “range of opinion”. Ideally, a skilled expert witness will fulfil this duty by expressing the relevant range of opinions and explaining in why, in their view, the evidence supports their position within this range rather than that of another expert.
Dr Sherlock summarised the best practice points and the panel highlighted a well-written example of a medico-legal report in Writing Medico-Legal Reports in Civil Cases by retired barrister Giles Eyre. This example clearly illustrates how the wording in a medical report addressing a sudden onset of accelerated symptoms can influence the lawyers’ calculations and the court’s assessment. In conclusion, the panel emphasised the best practice approach to be taken by expert witnesses and acknowledged the well-established guide for expert witnesses to “show their workings,” so as to make it easy for the court to accept their opinions in this type of case.