Reforming the law on expert evidence

Nowhere in the interface between medicine and the law is conflict more evident than in court. Although the two disciplines appear to have one thing in common -- to seek "the truth" -- the truth as relevant to medicine may well differ in nature from the truth as relevant to the law.

Further, the approaches used by the two disciplines to establish their respective truths are fundamentally different. Common law process is based on an adversarial system in which opposing parties present evidence to a judge or jury who determine the outcomes. Litigants construct their cases largely by selecting evidence that is advantageous to themselves, rather than the "absolute truth". In contrast, Western medicine is based on scientific evidence. It seeks to establish its "truth" through rigorous scientific methods which are foreign to the legal profession in its training and practice.

In the curial interface between medicine and the law, science is moulded into an uneasy and unnatural use within a system of intellectual combat alien to the scientific method. Enmeshed in this process are expert witnesses.

The task of the expert witness was characterised by The Hon. Gordon Samuels, Governor of New South Wales and past President of the New South Wales Court of Appeal, in his 1997 AMA (NSW) Oration Medical truth and legal proof (in this issue of the Journal). He described this task as twofold: "to furnish basic scientific or technical data", and "to present inferences and conclusions from the facts which the judge or jury, for lack of specialised knowledge, cannot draw themselves".¹ The duty of experts is to the court. They should impartially assist the court to understand the technical evidence, and not act as champions or advocates for the instructing and paying party. Understandably, some experts may find it difficult to recognise the need for impartiality and to accept this need if they have assisted in preparing the case before trial.

The challenge to the trial judge is to ensure that the expert is qualified on the issue before the court and that only relevant and reliable opinions are accepted from that expert. The problem is that the procedural rules relating to evidence permit the judge a wide-ranging power of discretion to carry out these duties. There is no threshold test in common law for the admissibility of expert evidence which takes into account its reliability. Evidence could be given by an academic with limited practical training, by a retired practitioner who has not practised for many years, or indeed by anyone with a recognised general medical degree without regard to specialisation. The discretion exercised by judges in some recent Australian trials has resulted in decisions which have caused concern in the medical community. The following cases are illustrative.

In Woods v. Lowns & ors,² the issue was whether it was reasonable for the defendant paediatric neurologist not to have prescribed rectal diazepam for epilepsy in a child in 1987. The plaintiff's expert from the United Kingdom asserted that the omission to prescribe rectal diazepam fell short of the standard of good medical practice, although he was aware, and the court accepted, that it was universal practice of paediatric neurologists in Australia in 1987 not to prescribe this form of the drug. Although this expert was expressly criticised by the trial judge for acting as an advocate for the plaintiff rather than as an independent witness, his evidence might appear to have influenced the resulting judgment.

Secondly, in Curtin v. Holliday & anor,³ a specialist oncologist gave evidence on the issue of early diagnosis of breast cancer by a general practitioner. The evidence of an expert in the advanced treatment of cancer is arguably irrelevant and perhaps unreliable in relation to the standard of practice applicable to a general practitioner. Thirdly, the evidence of a general surgeon on a renal physician's treatment of rhabdomyolysis was admitted by the judge in a jury trial,⁴ despite the surgeon's forced concession that he had never treated the condition, nor been involved in its management, and had not discussed such a condition at a scientific meeting. The general surgeon was arguably not qualified to provide the required evidence at issue.

Governor Samuels' oration discusses reform initiatives on the use of expert evidence in the United States and their potential application in Australia. The US Supreme Court, in Daubert v. Merrell Dow Pharmaceuticals, considered the issue of scientific validity of expert testimony.⁵ The decision outlined indicators which would assist a court in determining scientific reliability: whether the assertion can be and has been tested; whether the theory or technique has been subjected to peer review and publication; and the known or potential rate of error. These indicators represent a move away from the pre-existing test (widely, but not universally, in use in the US), which refers to mere "general acceptance" within a relevant scientific community. While this US decision has no direct applicability in Australia, the test for reliability may be a useful model for procedural reform.

Reforms have also been suggested in the UK, where Lord Woolf, Master of the Rolls, was appointed in 1994 to review the civil justice system in England and Wales. In his interim report, Lord Woolf recommended that the court should have "complete control" over the calling of expert evidence.⁶ This recommendation was reaffirmed, despite some opposition, in Lord Woolf's final report.⁷

In October 1996, the Chief Justice of the Federal Court of Australia, Michael Black, made some proposals regarding the use of expert evidence, and called for submissions from the Australian Law Council and other "professional bodies in the fields of economics, patents, trade marks, copyright, engineering and accounting".⁸ The Federal Court's initial proposal mirrored Lord Woolf's recommendation (above), but has since been amended to state that "the calling of expert evidence would usually be subject to the control of the parties, with the Court taking some control in exceptional cases".⁹ Other elements of the proposal included development of a code of conduct for experts, the requirement that expert evidence be addressed to the court, and the use of a panel of experts in a manner similar to that used with apparent success by the Australian Competition Tribunal. In this Tribunal, expert economists submit written statements before the oral proceedings. At the conclusion of all the evidence the experts give their opinions on the issues arising from the evidence and on the opinions of the other experts. They are entitled to modify their written views as much as they wish, so that the Tribunal can hear their present views after having access to all the evidence.

In addition, the Australian Law Reform Commission is including the issue of expert evidence in its review of the adversarial system of litigation in federal courts and tribunals.¹⁰

The Australian and UK initiatives are aimed at modifying the role of experts in the adversarial arena, so that they can metaphorically wear their laboratory or clinical coats rather than advocates' robes. The initiatives are likely to encourage judges to be more active as assessors, and thereby to make the common law system less adversarial. Interestingly, provisions in the New South Wales Supreme Court Rules permit, but do not oblige, judges to appoint their own experts.¹¹ In practice, these provisions have been rarely used, except in some patent cases.

Other possible reforms to the laws on expert medical evidence could include:

• The addition of a reliability threshold test, such as that outlined in the US Daubert decision;

• The requirement that evidence of accepted practice or standard within a specialised area be given only by someone with qualification and currency of practice in that specialised area;

• The involvement of learned medical colleges in establishing panels of accredited experts to be available to litigants and the courts, and in formulating a code of conduct for expert witnesses; and

• The adoption of some of the better elements of the Roman inquisitorial process in relation to expert evidence, such as the use of court-appointed experts or expert assessors to sit with, and advise, the judge.

The gap between medicine and the law is at its widest in the adversarial system of law. The proposals being considered by the Federal Court and the Australian Law Reform Commission should not be left entirely to the legal profession and the legislators, without input from other learned professions. Given the frequency of personal injury claims and the importance of medical expert evidence in these claims, the medical profession should take a significant role in the reform process.

Richard T T Tjiong
Chairman
United Medical Protection, Sydney, NSW

1. Samuels G. Medical truth and legal proof. Med J Aust 1998; 168: 84-87.
2. Woods v. Lowns & ors. Unreported, NSW Supreme Court, No. 14529, 9 Feb 1995.
3. Curtin v. Holliday & anor . Unreported, NSW Supreme Court, No. 20147/96, 19 Dec 1996.
4. Ford v. Garrick , NSW Supreme Court, No. 15966/88, 1994.
5. Daubert v. Merrell Dow Pharmaceuticals 113 Sct 2786 (1993).
6. The Right Honourable the Lord Woolf. Access to justice: interim report to the Lord Chancellor on the civil justice system in England and Wales. London: HMSO, 1995: 192.
7. The Right Honourable the Lord Woolf. Access to justice: final report to the Lord Chancellor on the civil justice system in England and Wales. London: HMSO, 1996: 139.
8. Black CJ. Letter to the Australian Law Council, dated 24 October, 1996. Available from the Registrar, Federal Court of Australia, Sydney, NSW.
9. Black CJ. Letter to the Australian Law Council, dated 20 August, 1997. Available from the Registrar, Federal Court of Australia, Sydney, NSW.
10. Australian Law Reform Commission. Review of the adversarial system of litigation. Issues Paper 20. Canberra: AGPS, April 1997: 7.76-7.79.
11. New South Wales Supreme Court Rules, Parts 39.2, 39.3.