Injury Law – Expert Witnesses: how to use, not abuse them

01 Jan 2003

By : Emily Formby

General principles

The rules for instructing experts, set out in the Code of Guidance on Expert Evidence and in CPR 35, are seemingly straight forward. In practice, they can give rise to more questions than they answer.

Selecting your expert

The first question may be, “is an expert needed at all?” In CPR 16PD.4 – the particular matters which must be included in personal injury particulars of claims – paragraph 4.3 states, “where the claimant is relying on the evidence of a medical practitioner the claimant must attach to or serve with his particulars of claim a report from a medical practitioner about the personal injuries which he alleges in his claim.” It will be a rare case in which medical evidence is not required, but the possibility is there. Its absence is not against the rules.

The court must also be persuaded to allow the evidence, since it will restrict expert evidence to that which is reasonably required to resolve the proceedings (CPR 35.1)

Having decided expert medical evidence is required, the next question: “who should I instruct?” may be harder to answer. A standard orthopaedic expert may not be the only expert required, or may not be the right discipline at all. In an acceleration of injury case or overlay of pre-existing injury, a rheumatologist may be more appropriate. The difference between a psychologist and psychiatrist should not be underestimated and can make the difference between success and failure.

Spend some time researching the type of injury if it is one with which you are not familiar. Do not be afraid to ask an expert whether they are the most relevant expert for the issues in the claim. Experts do not want to waste their time giving irrelevant evidence any more than you want to receive it. By defining the issues in the claim at an early stage you can be sure that the correct expert is identified.

From the defendant’s stand point this is no less crucial. If the claimant has properly complied with the pre-action protocol, the defendant’s solicitor will have had the opportunity to be involved at an early stage. As defendant, agreeing to an expert does not make that expert jointly instructed – the claimant can choose not to disclose the received evidence (Carlson v Townsend [2001] EWCA Civ 511; CA). However, it gives a valuable opportunity to have input into the relevant discipline as well as the actual expert chosen. Remember that the spirit of the pre-action protocol applies to all cases, not just those valued at less than £15,000.

Do not consider experts who are unable to give a CV as a matter of course, or are unable or unwilling to set out their experience and expertise in preparing reports and giving evidence. Experts should be able to provide:

  • Details of number of cases prepared in any year;
  • Break down of claimant/ defendant/ joint instructions received;
  • Accurate assessment of time required to prepare and serve the report (both time until an appointment can be given and time for producing report thereafter)

It is rare that there is only one expert in any field. Choose someone who not only fits your practical requirements but whom you find easy to talk to, who responds to your messages and is user friendly. You may find yourself spending time in court together or meeting for lengthy conferences. You need to be able to work well together.

It is preferable to choose an expert who is current in their field. Someone at the top of their tree, for the more difficult types of injury or illness, is better than the 95 year old who retired 20 or more years ago. While those who have recently retired (and so have time on their hands) can be ideal, do not be afraid to ask how long it is since someone practised or, if they have retired, how up to date they are with current medical thinking.

Even within common fields, such as orthopaedics, you may find a considerable range of experience or expertise. A spinal surgeon may not be best placed to advise on an ankle replacement. An orthopaedic expert with special interest in sports injuries may be a more relevant expert for the cycling accident claimant than a general surgeon. While it may be helpful to build up a list of experts with particular relevance or expertise, make sure that in so doing you have not fallen foul of the Data Protection Act 1998.

If you are using a medical report agency, check the names of the experts who are going to be instructed. The agency should be able to provide answers to all the questions set out above.

Costs of the Expert

Be careful when agreeing the costs of the expert. Cancellation fees are creeping up – both in amount and the date from which they are charged. It is well known that in most cases experts are never required to give evidence. Even in cases where evidence is to be called, settlement can occur in the last week before trial.

Remember that the Court’s power to restrict expert evidence extends to restricting the amount of fees and expenses that may be recovered from the paying party (CPR 35.4). Therefore, even if you succeed at trial, or on the claim, at assessment you may find the amount you have agreed to pay the expert being challenged. Your agreement, and your obligation to pay the expert, will stand, but the amount of money you recover to make that payment can be limited. If there is a shortfall it will have to be met as part of the solicitor/ own client costs.

As the paying party, make sure that you have accurate details of the break down of costs sought and, if relevant, the cost of your own experts. This can provide a good bench mark to test the reasonableness of your opponent’s claim. The timing at which cancellation costs were incurred can also be relevant. If costs were incurred before the issue of calling evidence was discussed, they could be disallowed.

Give clear instructions

Do not forget your expert is an expert in medicine, not legal matters. While it is increasingly likely he will have attended some training he will only produce a report as clear as the instructions given. Many will have considerably more experience in writing reports than in defending them under cross-examination at trial.

“Give a general view on prognosis” is unlikely to address the key issues in a case. Having defined the issues when choosing the expert, it should be short work to refine those issues into instructions. Set out the questions you require answering as part of the advice. Do not be afraid to ask direct questions about previous medical history, even highlighting points in the medical notes if relevant.

Bear in mind that instructions are not privileged, the expert’s report must state the substance of all material instructions, whether written or oral, on the basis of which the report is written (CPR 35.10). On occasion there may be cross-examination of the expert on these instructions (CPR 35 PD.4). While rare, this risk should prevent the instructing solicitor writing a “side letter” or asking questions that are not to be answered in the main report. Further, the expert’s duty is to give evidence which is the independent product of the expert, uninfluenced by the pressures of litigation (CPR 35 PD.1.2). Therefore, questions raising queries on general issues must be carefully phrased.

If jointly instructed, the letter of instruction will either be agreed by both parties or will be disclosed to the other instructing parties (CPR 35.8).

Give relevant information

To provide the report, the expert will need access to the medical records. In all but the simplest cases, a bundle of medical records should be prepared and paginated. This will enable all experts to refer to the same evidence. The legal team can be confident the experts have seen all of the evidence (experts can on occasion miss relevant entries). The experts can cross-refer to one another’s reports with ease. The judge will be able to follow the evidence.

Preparing such a bundle will usually be the task of the claimant’s solicitor. However, it may depend on some co-ordination with the defendant if it holds medical or relevant information. If the claimant does not volunteer such a bundle, or the defendant is concerned it has not had sight of all the medical records, ask for a suitable direction at the case management conference. As a defendant’s adviser do not be content with partial disclosure of records: GP notes after the accident or records passed from the claimant’s solicitors after “vetting”. The Court will be sympathetic to an application for full disclosure, if warranted. Do this as early as possible.

It must be borne in mind that expert evidence is to be restricted to the necessary issues. In a fast track claim, the evidence will not be expected to be given live – a written report will be the norm (CPR 35.5(2)). Therefore, best preparation of the written report is vital since it will often be the only evidence at trial.

To disclose or not to disclose?

Once the report is to hand, questions can be asked of the expert. Each party has the right to ask questions of the other party’s expert, or a jointly instructed expert, within 28 days of receipt of the report (CPR 35.6). It is important to remember that once a medical report has been disclosed it can be relied upon by any party, therefore if you abandon an expert during the course of the proceedings you are unlikely to avoid their adverse findings entirely (CPR 35.11).

Further, the expert, whose duty is to help the Court, must set out the whole of his opinion and the factors which are relevant to the reaching of this opinion. This duty is not without controversy since parties (and indeed experts) do not always agree what factors are relevant, nor indeed, whether these are within the expert’s area of expertise.

Further guidance can be found in the practice direction which states that the expert’s duty is to help the court by providing objective unbiased opinion on matters within his expertise, and he should not assume the role of an advocate (CPR 35PD.1.3) Therefore, if the expert has strayed into areas of evidence: stating which position is preferred – or even evaluating evidence – it may be possible to obtain direction from the Court that the scope of the evidence be restricted or the expert directed to give opinion on relevant issues only.

It is also the expert’s duty to communicate straight away to all the parties and (where appropriate) the court any change in view on a material matter made after writing a report (CPR 35PD.1.6). Therefore, if further evidence, medical records or reports lead an expert to changing his mind, it is not possible simply to rely on his first or earlier report. The change of mind must be communicated to the parties.

On occasion, experts will write a “side letter” or a covering note which does not form part of the main report. This is to be discouraged. If the letter contains a statement of opinion which is not found in the report, then it must be disclosed.

Dealing with the Joint Expert

There can be particular problems when dealing with the jointly instructed expert. You may not like the evidence received. While you will have had input into the instructions and the definition of issues, where there is a range of opinion and the expert had reached an adverse conclusion, it can be hard to attack.

Remember, where there is a range of opinion, the expert does have to summarise it and, if he or she has taken a particular view, explain why (CPR 35PD.1 and CPR 35PD.2 (6)). In reality, since the Court is likely to be guided by the expert, this may not help.

As the recipient of the hostile advice, it is important to act quickly, rather than simply wait for trial. Daniels v Walker [2000] 1 WLR 1382; CA, made it clear that the joint instruction of an expert by the parties is a first step in obtaining expert evidence. In many cases it will be the last.

However, if one or other party is dissatisfied with the evidence:

  • Ask questions of the joint expert (this can be done by right pursuant to CPR 35.6);
  • Obtain your own expert evidence (there is at this stage no right to call such evidence so the other party should not disagree – even if the claimant has to undergo further examination);
  • Consider the new report in the light of the joint evidence and the questions;
  • Arrange for a meeting between the 2 or 3 experts;
  • As a last resort obtain leave to call the experts to give oral evidence at trial.

It is important that the Court is kept informed of these steps by way of case management. A good direction to seek, upon receipt of an unsatisfactory joint report, is to ask questions and then have leave to obtain relevant expert evidence, if so required. This is still a step away from calling the evidence at trial, but will obviate the need to return to Court for a further hearing. The directions may be:

  • Ask questions of the expert;
  • Leave to obtain own expert evidence to be disclosed, if relied upon, by a set date;
  • Order for a discussion between the experts and provision of a joint report by a set date;
  • Pre-trial review or further directions at which the issue of calling expert evidence, as necessary, can be decided upon.

If the issues in the claim are well defined before the first expert is instructed, it may be that the further expert evidence will only need to address the issues that remain between the parties, the area of the report with which there is disagreement.

It should be borne in mind that, as with all areas of civil litigation, the extent to which the Court will allow the parties to ask questions, instruct experts and call evidence will depend on the issues at hand, the proportionality of expense to value of claim and compliance with the overriding objective.

This article first appeared in the New Law Journal Expert Witness Supplement, on Friday 22nd November 2002; New Law Journal Volume 152 No 7057 page 1756


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