The role of expert witness is interesting and potentially lucrative but there can be drawbacks too, so think hard before making a commitment, says Dr Gerard Panting


Expert medical evidence is required in virtually all personal injury claims, including clinical negligence litigation, road traffic accident claims and some employment disputes, and, frequently, in the criminal courts.

Being an expert carries with it a degree of kudos, offers different and often very interesting work and extra income. However, on the downside, once you are involved in a case, the legal process can place significant demands on your time and, as not all commitments are negotiable, experts may be subjected to considerable inconvenience.

Furthermore, medical experts are not immune from criticism in the courts and can even end up facing a bill for wasted costs or a negligence action if losses result from a deficient report. Last, but by no means least, a complaint to the GMC may be the start of a lengthy conduct inquiry with all that it entails.

The expert witness

What is an expert? The Society of Expert Witnesses says:

"An expert is anyone with knowledge or experience in a particular field or discipline beyond what is expected of a layman. An expert witness is an expert who makes his or her knowledge available to the court (or other judicial or quasi-judicial body) to help it understand the issues of a case and reach a sound and just decision.”

That definition is in one sense misleading – to compare the knowledge of an expert with that of a layman might be construed as allowing any medically qualified practitioner to opine on any specialist medical issue, which would clearly be a nonsense. In the Bolitho case, the House of Lords stated that "The medical opinion relied upon must be deemed reasonable and responsible and have a basis in logic.”1

As far as medical matters go, experts should limit their opinions to areas within their expertise and day-to-day practice.

Expert evidence may be required at several points in any given case. Initially, advice may be required – this will include identifying the strengths and weaknesses of the claim, the need for further expert opinion or identification of documents that will clarify issues in the case.

Any advice given at this stage is protected by legal professional privilege and is not disclosed to the other side, with the expert owing a duty of care to the client.

As soon as litigation is under way, the situation changes – now the expert’s overriding duty is to the court. Reports must be addressed to the court and questions may be put to the expert by the other side. The expert should be objective and not partisan – let alone a hired gun. Any lack of objectivity at this stage may rebound with potentially serious consequences.


Experts are generally instructed by solicitors. The brief should set out what is required of the report and the ‘business’ arrangements, including when the report is needed and payment terms.

The instructions should clearly state who is involved, the client’s details and the chronology (the key to understanding any claim), exactly what the expert is required to give an opinion on, what the report is required for, what documentation is accompanying the instructions and what stage of legal proceedings (if any) has been reached. If any details are lacking, now is the time to ask for clarification.

It is up to the expert to decide whether or not to accept the instructions. A large workload and not possessing exactly the right expertise are two good reasons for declining.

If the expert accepts, the report should be delivered within the agreed timescale. Advisory reports may be addressed to the solicitor but formal reports to be used in litigation must be addressed to the court. They must be unbiased, include any reservations the expert may have and supply references (for instance, to relevant medical literature) that may assist the court in deciding the case.

The civil procedure rules require that the report should also detail the doctor’s qualifications, who provided the instructions and a chronology of events. It should also give details of all the documents or other evidence examined, a summary of the conclusion reached and a statement of truth.

Factual disputes

It is rare for claimant and defendant to agree exactly on what happened when and where. Where there is a factual dispute, the expert should give an opinion for each potential version of events unless one account is considered improbable or implausible, in which case he or she should say so.

Further involvement

Although it is comparatively rare for clinical negligence claims to go to court, submitting a report is unlikely to be the end of the expert’s involvement. Further questions are likely to be raised, including by the other side, in which case they must be answered within 28 days.

The instructing legal team may require the doctor’s presence at conferences to discuss the continuing merit of the claim and it is now common practice (in England and Wales) for the ‘opposing’ experts to meet to identify points of agreement and disagreement.

These meetings may be face to face or over the telephone and, whatever the format, a statement must be prepared following the meeting recording the points on which agreement was reached.

Meetings of experts can, in effect, conclude the case – solicitors cannot tell ‘their expert’ what or what not to agree, and once conclusions are reached and committed to the joint statement, there is no going back.

If the experts manage to conclude what would have been issues at trial, there may be nothing left to litigate.

Attendance at trial

For experts involved in the few cases that do culminate in a trial, it is imperative to be available on the agreed dates, as one case illustrates (see Box, below).

A cautionary tale

A consultant paediatrician who had frequently assisted the police and courts in child abuse cases attended the crown court as a professional witness, only to find that the case had been postponed.

A second date was fixed; the consultant had told the police that he was only available in the morning, but when he arrived at the court he found that the case was scheduled too late to allow time for his cross-examination. The case was postponed again and the consultant gave the police a list of dates on which he would be available.

Later, a policeman contacted the consultant’s secretary with a date for the trial. The secretary told him that the consultant could not attend on that date as he had a particular clinic to attend. The police officer said that he would see what could be done.

The consultant heard nothing more until the morning of the date previously given to his secretary, when he received a call asking why he was not in court. He explained that as he had received no written notice (as he had on the two previous occasions), he had assumed that a date had not yet been set for the court case. He offered to go to court after completing his clinic but was told that it was already too late and that the judge had dismissed the case. Moreover, the judge had stated that the doctor was in contempt of court, that a summons would be issued to require his attendance, and that if he did not appear then he would be arrested.

The doctor duly attended court at the required time and, perhaps unwisely, said that rather than having the matter adjourned so that he might obtain legal representation, he would prefer it to be dealt with and concluded.

The judge, accepting as fact what counsel had told him at the previous hearing, stated that the court had been treated with contempt. The doctor was given no opportunity to challenge what the judge had been told. Brushing aside the consultant’s attempt to explain himself, the judge found him in contempt of court and imposed a fine of £250.

MPS took the matter to the Court of Appeal. The Lord Chief Justice, who presided at the hearing, found that the judge’s decision had been wrong; he had failed to hear any evidence and, moreover, had come to his decision before giving the consultant a chance to speak in his own defence. The Lord Chief Justice quashed the conviction and awarded costs to the consultant; counsel representing the interests of the trial judge raised no objection.

The fine was duly refunded and application was made for reimbursement of the £6000 in costs incurred by the MPS.


Being a medical expert is demanding in a variety of ways but can be intellectually and financially rewarding.

Legal cases are pored over in minute detail and experts must expect their reports to be subjected to the same degree of scrutiny as all other aspects of the case. Criticism of expert witnesses is not inevitable, but any loose wording in reports is likely to be examined in great detail.

Hostile cross-examination, although not routine, is always a possibility, so if this is not the sort of environment you would like to find yourself in, providing expert reports is best avoided.

  1. Bolitho v. City and Hackney Health Authority [1997] 3 WLR 582.

Guidelines in Practice, September 2004, Volume 7(9)
© 2004 MGP Ltd
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