Case for the single expert

In his report Access to Justice, Lord Woolf referred to a number of cases when discussing the duties of expert witnesses. One was Whitehouse v Jordan (1981), in which Lord Wilberforce said: “It is necessary that expert evidence presented to the court should be and should be seen to be the independent product of the expert uninfluenced as to form or content by the exigencies of the litigation.”

A rather different emphasis on the role of the expert witness appeared in the High Court decision in Blue Circle Industries plc v The Ministry of Defence, where judgment was given on 26 November 1996.

In the course of his judgment, Mr Justice Carnwath said: “The exercise was complicated by the number of dates at which valuations were attempted, ranging from 1989 to 1996. This was not necessarily the fault of the valuers, since they were in this respect complying with their instructions. However, it underlines the importance of not simply leaving these matters to the valuers.

“The exercise of refining the valuation evidence and narrowing differences requires the cooperation of valuers and lawyers. Of course, the latter should not seek to influence the expert opinion of the valuers, but their assistance is essential in order to ensure that the valuers are directing their attention to the critical issues, and that the material is presented to the court in as clear and economical a way as possible.”

It can be misleading to take too literally Lord Wilberforce's familiar warning that evidence should be “uninfluenced as to form or content by the exigencies of litigation” (Whitehouse v Jordan (1981) – which was spoken in the very different context of medical negligence. It is the lawyers' duty to assist in the process of narrowing the issues and simplifying the evidence, and to ensure that the form and content of the material presented to the court adequately reflects this process.

These conflicting views place the expert witness in a difficult position when deciding how much he should be guided by instructing solicitors and counsel.

In his final report, Lord Woolf quoted with approval a form of declaration that had been proposed by the Working Group on Intellectual Property. This declaration would include, among others, statements that the expert:

has endeavoured to be accurate and complete, and to mention all matters which he regards as being material to the opinions he has expressed;

has drawn the court's attention to any matter of which he is aware which might affect the validity of his opinions;

understands that if the court concludes that he has not fairly tried to meet the standards set out in the declaration, he is likely to be the subject of public criticism by the judge.

Access to Justice indicated that “this outline sets out the points that should be included in an expert's declaration”.

However, it seems there is a possible conflict between the Working Group's entreaty to the expert to mention all matters which he considers to be material and Mr Justice Carnwath's view, as quoted above.

The whole tenor of Lord Woolf's approach is that expert witnesses should provide unbiased assistance to the court. The expert will be bound to deal fully in his report with every factor which, in his view, is material to the matter with which he is concerned. There is a potential incompatibility between this duty and the lawyers' duty to simplify the evidence as referred to in the judgement of Blue Circle Industries plc. It is to be hoped that the continuing consultation process which is being undertaken by the Lord Chancellor will find a way of resolving this problem.

The interim report favoured the appointment of what it described as the “court expert”. It suggested: “Rules of court should allow the court to appoint an independent expert of its own motion and to limit the parties' power to call any expert except under the direction of the court.”

It is clear that the proposals for court experts produced vociferous opposition from members of the legal profession. As a result, the final report abandoned the term, referring instead to “single experts”. Indeed, in a clear acceptance of submissions received from the legal profession, the final report stated firmly that: “I do not think it would be appropriate to specify particular areas of litigation where a single expert should or should not be used.”

Nevertheless, the report concluded that the appointment of a single expert was desirable in principle and should be encouraged by the courts.

Although single experts may be unusual in many disciplines, surveyors have long been accustomed to them. The majority of rent review disputes provide for determination by a single surveyor. Although many leases require the surveyor to act as arbitrator, a substantial percentage state that he is to act as an independent expert.

It is almost inevitable that one party at least will be disappointed by the determination of such an expert. However, where there is dissatisfaction, the degree of such dissatisfaction is generally no greater than in cases where the determination is made by an arbitrator or by a judge. The important considerations are that the surveyor must be recognised as being both impartial and an expert in his field.

Against this background, there is considerable merit in single surveyor experts being appointed to assist the court in property-related litigation. Ideally, the expert should be appointed by agreement between the parties. But that it is often difficult for parties locked in a contentious dispute to bring themselves to accept any expert suggested by the other side. On the other hand, appointments made following an application to the president of the Royal Institution of Chartered Surveyors are generally considered acceptable by both parties and the court would probably use the services of the RICS to appoint an appropriate person.

It is essential that the role of the single expert is to assist the court to resolve the matters in issue between the parties. The final decision must remain with the court. Single experts in court proceedings should be prepared to receive submissions and counter-submissions from the parties, and they should then provide reasons for their determinations and be prepared to face cross-examination by the parties. If this procedure was adopted, then it would often seem reasonable for the court to direct that oral evidence on the surveying issue should only be given by the single expert.

Such a procedure should reduce the length of the trial in comparison with the present system, since the number of surveyor witnesses would be halved. At the same time, the parties would still be able to call upon the assistance of their own surveyors, whose views would be incorporated into the written submissions to the single expert and could subsequently form the basis of cross-examination.

While additional costs will arise from the appointment of a single expert, we consider it is likely to reduce the overall costs of most actions, where valuation is the main point in dispute, provided the expert issues a determination at an early stage in the proceedings.

The conclusions of the expert, however unpalatable to the parties, will generally be of strong persuasive influence on them in their settlement negotiations. As a result, such negotiations should often be concluded at a much earlier stage than at present.