Bring your own

The 50th update to the Civil Procedure Rules, which came into force on 1 October 2009, takes further steps towards the courts limiting the use of expert witnesses in personal injury claims. In particular, the amended rule 35.4(3A) makes it clear that in both the small claims and fast track cases a single expert on any issue should be the norm.

Although these changes ought to assist in keeping litigation costs to a minimum, there will remain instances where a party will seek the instruction of separate experts to do justice to their case. It is at least arguable that the view of just one single expert, no matter how conscious of their overriding duty to the court, should not always be binding upon parties who disagree with their opinion. The authorities existing prior to the 50th update showed that there were a number of circumstances when additional experts could be called in. Practitioners coming to terms with how to get the best out of expert witnesses should still have regard to these authorities when seeking the court's permission to go beyond the one expert per issue principle.

We should recall that when the Civil Procedure Rules 1998 were introduced they sought to address, in part 35, what was perceived as one of the major contributors to the length and cost of litigation: the excessive use of experts. The rules sought to control and simplify their use, empowering the court to restrict expert evidence to that 'which is reasonably required to resolve the proceedings' (CPR 35.1). Although the Woolf committee had envisaged greater use of single experts, this was strongly resisted during consultation. In his final report ('Access to Justice', 1996) Lord Woolf acknowledged that there are 'in all areas some large, complex and strongly contested cases where the full adversarial system, including oral cross-examination of opposing experts on particular issues, is the best way of producing a just result'. In particular, he identified issues on which 'there are several tenable schools of thought, or where the boundaries of knowledge are being extended' as circumstances justifying separate experts.

Despite the fact that medical knowledge is continually expanding, and is often characterised by expert disagreement, in personal injury cases the use of single experts is strongly encouraged by the rules. The pre-action protocol requires a party to nominate a list of one or more expert(s) it wishes to instruct, and gives the other side 14 days to object to some or all of the nominees. Defendants receiving such a list will be particularly keen to object to an inappropriate expert given that the court may, under CPR 35.7, appoint that expert as a single joint expert. Indicators that an expert is inappropriate could be that they are no longer practising; do not have the correct level of expertise or seniority for the issues being considered; or there are clear indicators in their CV or in their contribution to reported cases that they may not be best suited to the case.

A party (or both parties if there is a single joint expert) is entitled to put questions to the expert within 28 days of receipt of their report for the purposes of clarification. Case law has previously established that questions should not amount to cross-examination (see Mutch v Allen [2001] EWCA Civ 76), and the newly amended CPR 35.6(1) states that questions must be 'proportionate'. As a result, questioning an expert '“ although it can be useful to obtain more details of an injury, a better explanation for the conclusions reached or to clarify other issues '“ is of limited use in fundamentally challenging an expert's medical opinion.

Two's company

Unless the evidence served by an expert instructed by the other side is reasonably non-contentious or the claim is of low value, instructing a separate expert is usually preferable. By obtaining an alternative view, it becomes possible to fully explore issues in conference without having to involve the other party, which puts the parties on a more equal footing. Furthermore, if the separate expert's report highlights significant weaknesses in a party's case, their solicitor will be in a better position to advise on settling the claim, which will assist with negotiations.

However, the court's permission must be sought for any report to be relied upon in subsequent court proceedings (CPR 35.4). It is almost impossible for such permission to be obtained for small claims track matters, and, as a result of the updated CPR 35.4(3A), the courts will prefer a single joint expert for the fast track. Nevertheless, if a desktop report has already been obtained from a separately instructed expert, this can be exhibited with any application to persuade the court of the merits of allowing reliance on a separate expert.

The updated guidance for the court to consider when deciding whether to order a single joint expert is provided by CPR PD 35.7, which adds to the relevant factors identified by Lord Neuberger (then a High Court judge) in Cosgrove v Pattison [2001] CP Rep 68. If seeking permission for separate evidence, it is important to tailor submissions to the factors set out in this practice direction. For instance, it may be argued that 'questions put to a single expert may not conclusively deal with all issues which require testing prior to trial' (PD 35.7(g)). Parties should also not forget the overriding objectives when seeking permission. Often, the point can be made that a separate expert, able to discuss matters with the opponent's expert, will assist the parties, and the court, to narrow key issues.

Given the risk of prejudice to one side, it is no surprise that a large body of case law has developed in this area. The primary authority remains Daniels v Walker [2000] EWCA Civ 508. The defendant agreed a joint occupational therapist, but was dissatisfied with the expert's opinion. Lord Woolf MR (Court of Appeal) allowed the appeal against the refusal to give the defendant permission to instruct a separate expert to examine the claimant. He gave guidance on instructing additional experts, making it clear that in most cases obtaining a joint expert report was to be the norm, especially where a 'modest' sum was involved. However, where more substantial damages were at stake, a separate expert could be justified if the defendant's explanation for their disagreement was not 'fanciful'. However, in a later Court of Appeal case, Peet v Mid Kent Healthcare Trust [2002] 1 WLR 210, Lord Woolf held the applicant had to show 'good reason' to instruct a new expert, which appears a slightly higher test.

In some cases, a court may permit a number of separate experts. For instance, in ES v Chesterfield and North Derbyshire Royal Hospital NHS Trust [2003] EWCA 1284, the claimant appealed the master's order that expert evidence in the field of obstetrics should be limited to one expert per party. The claimant argued the order put her at a disadvantage: her expert would be confronted with the trust's expert and the two obstetricians, accused of clinical negligence. It was inevitable they would testify they had acted in accordance with an appropriate standard of care, and that the imbalance in the number of witnesses with clinical expertise would disadvantage the claimant. The Court of Appeal held the court's discretion should be exercised flexibly. It would therefore be wrong to approach the question with a predetermined belief that it would always be excessive to instruct more than one expert in the same discipline. The claimant was allowed to call two experts in the field of obstetrics.

Although the value and complexity of these claims and their importance to the parties were clearly influencing factors in these cases, the factors considered by the court offer useful guidance.

Expert shopping

However, the exercise of the court's discretion under rule 35.4 will be affected if there is a suspicion that a party is attempting to cherry-pick expert evidence to suit them. The courts do not want to be seen condoning 'expert shopping'. Solicitors should be wary of creating this perception, and oppose any such behaviour by an opponent.

Stallwood v David [2006] EWHC 2600 is a rare instance of parties being allowed to change experts. The claimant appealed a decision refusing permission for a second medical expert following the first expert's change of opinion, after discussion with the defendant's expert. It was held that any party that believed an expert had stepped outside his expertise, or had acted incompetently in reaching agreement, could apply for an alternative expert. Further, a court has discretion to allow a party to adduce a further expert if there was good reason to suppose the first expert had modified their opinion for reasons which could not properly and fairly support their revised decision.

More typical is the subsequent case of Singh v CS O'Shea [2009] EWHC 1251, which makes it clear that where the first expert has revised their opinion for good reason '“ in this case in light of new evidence '“ a party should not be permitted to cast them aside (see also Read v Superior Seals Ltd [2008] CLY 267).

Expert management

Given an expert's overriding duty to the court (rule 35.3), the ways in which solicitors can control an expert once instructed are limited, except to the extent that intelligent questions can guide them towards the key issues. However, it is still important that experts are managed in a pro-active fashion, that their evidence is obtained at the first reasonable opportunity, that it complies with the requirements of the CPR and is served in time.

Crucial evidence

Obtaining high-quality expert evidence is crucial to effective case management. Solicitors can assist by ensuring the expert is provided with all relevant material, clear instructions, and a clear understanding of the issues they need to address.

The impact of expert medical evidence in personal injury claims can not be overstated. Judges look to experts for assistance on interpreting the facts, which are often meaningless without a considerable degree of medical expertise. The non-partisanship of experts is safeguarded to an extent by the CPR, but experts are not infallible. For justice to be best served, their evidence should be open to proper scrutiny and challenge if a solicitor is dissatisfied with their opinions for a legitimate reason. On balance, the authorities prior to the latest update of part 35 gave means for redress. It is dearly hoped this continues to be so.