THE JUDICIAL REVIEW

EXPERT EVIDENCE:  CAUSATION, PROOF AND PRESENTATION^*

The Hon Justice Michael Kirby AC CMG

^**LAW IN THE WORLD OF SCIENCE AND TECHNOLOGY

          The initiative of Monash University Law School in Australia in setting up the world's first International Institute of Forensic Studies is timely, and admirable.  I congratulate Professor (formerly Justice) George Hampel on his imagination and lateral thinking in linking this endeavour with the other for which he is justly honoured, namely the Australian Advocacy Institute, of which he is chairman.  A concern about forensic studies necessarily overlaps with a desire to improve advocacy standards.  Forensic studies today must address the growing complexity of technology. It must do so in the highly structured world of formal decision-making.

          Every judicial officer, and most members of independent tribunals, have from time to time to consider the admission of expert evidence. In earlier times, most such evidence, at least in civil trials, was medical testimony.  Sometimes such testimony was relatively clear-cut - addressed to whether a particular medical condition (typically on the part of a claimant for money compensation) was caused by a specified injury or whether physical incapacity was consistent with the injury complained of and sufficiently serious to support a contention of inability to perform specified activities.  In the case of such medical evidence, proof that the expert was trained in the medical discipline, and certified or otherwise qualified to practise in that discipline, was enough to oblige the admission of the evidence before the judge, jury or tribunal.

          However, with the advances in scientific knowledge and the increase in technological capacity, the proof, reception and consideration of forensic evidence has become much more complex.  The three great advances of science in the twentieth century were nuclear physics, informatics and genomics.  These three are, of course, inter-related.  Without nuclear physics, it is unlikely that the space programme would have got off the ground.  Without the space programme, the need to miniaturise data processing would probably not have been felt.  Without such miniaturisation, there would have been no computers and telecommunications would have remained primitive.  Without computers, the analysis of the human genome would have been painfully slow, perhaps impossible.  Certainly, it would not have been possible to map the human genome and to complete the Human Genome Project within the fifteen years fixed when that project was launched in 1990.

          The difficulty for humanity presented by these technological advances, is that, unlike the mechanical technologies of earlier generations, it is not now possible even for highly intelligent and well educated lay people, to comprehend the details of the sciences that I have mentioned or the technologies that have come in their wake.  Lay observers can comprehend some of the political, social, economic and personal implications of nuclear physics, informatics and genomics.  But they find it difficult to understand exactly how these sciences actually operate.  What Einstein's theory of relativity really means?  What is an atom?  What causes a chain reaction?  How does a computer actually operate?  How is a message on the Internet technologically "uploaded" and where precisely (if anywhere) the source of the electronic signals exists?  How genes in fact adhere to the double helix and how they actually operate to cause their physiological manifestations in an actual living human being?

          The incapacity of even educated people to understand questions such as these presents serious social consequences for every legal system.  For example, they make it difficult to expect prompt responses from national legislatures, still less from international institutions, to the social implications of the comparatively rapid advances in human scientific and technological capacity.  In Australia, recently, we witnessed an instance of this difficulty.  I refer to the debates occasioned by the proposed involvement of our scientists in the cloning of human stem cells for therapeutic (but not reproductive) purposes.  Ensuring that parliamentary democracies can respond in informed and rational ways to such developments is a major challenge for the ongoing success of democratically accountable lawmakers.  Unfortunately, the experience of the past century teaches that the number and complexity of the scientific and technological advances will increase rather than diminish.  This presents a critical institutional problem^[1.

          During the past two decades I have had the good fortune to work on the legal ramifications of two of the three scientific areas identified, namely within the OECD on the implications for privacy and data security of informatics and within UNESCO, HUGO and elsewhere on the ethical implications of genomics.  This experience has taught me the urgent need to adapt our constitutional, judicial and legal systems to the realities of the world of science and technology that exists today.

          One segment of that adaptation concerns the way in which courts and tribunals, as part of the constitutional system for resolving criminal and civil disputes, do so where the dispute is affected, to whatever degree, by the resolution of a contested issue of expert scientific evidence.  Everyone who deploys public power in a country like Australia - legislative, executive or judicial - does so on behalf of the people.  It is therefore necessary for those who enjoy that privilege and obligation, to find efficient and accurate ways to exercise their power when it involves contested questions of a scientific or technological character.  This is the subject that I wish to address.  It is timely to do so because the Australian Institute of Judicial Administration has recently published a comparative study in the survey of Australian magistrates concerning their perspectives on expert evidence^[2.  This report followed an earlier one concerned with the perspectives on expert evidence of judges throughout Australia^[3.

          From an analysis of these reports it may be hoped that some lessons can be drawn that will assist judicial decision-makers, and the advocates who appear before them, in resolving contested questions of causation and in improving proof and presentation of expert evidence where this is likely to be determinative of the outcome of a criminal or civil case.

EVIDENTIARY CONFLICTS AND COURT EXPERTS

          It should not be thought that the problem of receiving contested expert evidence, and deciding between differing expert opinions, is a new one.  Such problems existed long before the advent of nuclear physics, informatics and genomics.  Recent developments have simply exacerbated the problems and increased their complexity.

          From time to time, including in the recent surveys of judges and magistrates in Australia, proposals have been made to resolve contests between experts by the simple device of the court appointing its own expert in the discipline concerned.  Such a person, it is hoped, would objectify the process of decision-making; ensure the most reliable and up to date evidence for the decision-maker; and maintain standards of scrupulous impartiality such as befits the making of contested decisions in courts of law or independent tribunals.  On the face of things, this seems a sensible solution^[4.  It has some analogies in specialist fields of legal practice, as in the entitlement of a judge, conducting a disputed claim to intellectual property rights, to appoint an expert in the field to assist the court^[5.  In such cases, the courts were always at pains to insist that, depending on the governing law, the judicial officer, with or without cross-examination, should secure whatever help was possible from the "independent" report but without necessarily being bound to accept it^[6.

          Beguiling as may seem the notion of transferring difficult questions from a judicial responsibility to independent experts, anyone who has had even a brief acquaintance with the practical running of cases in courts will know that such a solution would not necessarily be just or appropriate^[7.

          When I was a young legal practitioner, engaged in workers' compensation cases, I soon learned of the high quality expert witnesses who would give evidence on contested issues, generally favourable, or opposed, to the causative relevance of work-related incidents to a given medical pathology.  Thus, in the field of cardiac catastrophes, there was a well-known list of physicians who would offer their opinions that coronary occlusion was never caused or precipitated by unusual effort.  On the other hand, there was list, equally long, of physicians who held that such cardiac catastrophes were often, if not invariably, related to some external or internal effort, including that associated with work^[8.  The witnesses were equally impressive.  Some of them were truly outstanding in the oral presentation of their opinions.  Most importantly, I quickly came to the view that virtually all of them were speaking with complete sincerity, personal neutrality and integrity.  They were doing so by reference to their individual experience and to a mass of conflicting research and scientific data.  This was not a case of fraudulent evidence or evidence motivated by self-interest, in the hope of building a forensic practice.  It was simply a difference, deeply held, of medical aetiological opinion^[9.

          If the solution of choosing a court appointed expert had been adopted in such a case, it is beyond doubt that the selection of an expert from one list or the other would, effectively, in practice have determined the outcome of most cases.  Unless the judicial officer rejected the technical evidence of such an expert, and substituted his or her opinion based upon temporal or other probabilities^[10, the power of decision-making would effectively be transferred from the independent court to the expert.  In a case involving a claim for compensation this could, in a particular matter, be seriously unfair to a claimant or a defendant and its insurance company.  But in a case concerning a criminal trial, it could be calamitous - most especially because much of the expertise and routine experience in the forensic areas of scientific importance to criminal trials ordinarily resided in police or other public authorities, generally working in support of the prosecution.

          My experience with expert forensic evidence presented me, as a young lawyer, with the basic problem of contested expert testimony.  It also tended to knock over the solution, commonly propounded, of court appointed experts.  Such a solution might work in some areas.  But in the areas with which I became familiar, it would have foreclosed neutral decision-making.  With all its imperfections, committing a contested issue to an independent decision-maker, obliged to choose from the logic of the case and the evidence between contesting experts, seemed a better solution than evading the problem by appointing a court "expert".

AUTONOMIC DYSPRAXIA AND CONTESTED EXPERTISE

          As it happened, soon after I began to practice, a case was argued before the High Court of Australia concerning the approach to be taken to conflicting evidence.  In Commissioner for Government Transport v Adamcik^[11, the claimant, a widow, sought damages for a fatal injury to her husband.  He had been a tram conductor in the employ of the Commissioner.  Before his accident he had been in apparent good health with no apparent manifestation of any disease.  Then, through negligence, he was knocked off the tram.  He was admitted to hospital and discharged after ten days.  Three days later symptoms of leukemia appeared.  Three weeks later still he was re-admitted to hospital with a diagnosis of acute lymphatic leukemia.  Six months later he died as a result of this condition.  The claimant alleged that his death had resulted from the initial accident. 

          Substantial expert medical evidence was called to the effect that leukemia was a disease of unknown origin.  The defendant's experts, medical witnesses of great distinction, stated that it was most unlikely that the onset of the disease was caused by trauma in the accident.  In their opinion, that onset was probably no more than a coincidence - although they could not say that a relationship was impossible because the state of medical science had not reached the point of specifying all of the incidents of leukemia.

          Obviously, in favour of the claimant widow was the sheer temporal sequence of events described.  However, decision-makers must often be reminded (and remind themselves) of the fallacy of post hoc ergo propter hoc, ie because an event follows another in point of time does not necessarily mean that it was caused by the other^[12.  The issue in the case became had the widow, in her case, produced sufficient evidence of causation to sustain the decision, which was a verdict of a jury in her favour.

          Issues of causation often present the trickiest part of claims for damages or compensation dependant on medical evidence.  Mrs Adamcik's case was an illustration of those difficulties.  On the point in issue, the High Court divided.  The division concerned the weight (if any) that could properly be given by the jury to the evidence of a minority medical opinion tendered before the jury by Dr B G Haines.

          Dr Haines was not only a graduate in medicine and a member of the Royal College of Physicians.  He was also a consulting physician and an honorary physician at a large Australian public hospital.  He gave evidence that, in his opinion, emotional disturbances operating in conjunction with other agents could be a factor in producing leukemia.  Under cross-examination he went further.  In the words of Justice Windeyer, he asserted, "without qualification or restraint"^[13 that "mental states and emotional disturbances are the cause of all, or nearly all, diseases except those of infective origin".  Dr Haines agreed that this was not an accepted view.  He agreed that, as yet, he was unaware of positive adherents to the view other than himself.  But he claimed that medical science was coming steadily to the idea and he expected that, in due course, it would receive general recognition.  Dr Haines had published a book on psychosomatic medicine under the title Autonomic Dyspraxia.  This was his theory and he stuck to it.  The lawyers for the Commissioner dismissed it as "the assertion of an eccentric person that the earth is flat"^[14.  For them, it was not true evidence.

          Justice Windeyer rejected the "flat earth" analogy.  Indeed, he pointed out that Dr Haines could claim that it was others, not he, who, through ignorance or orthodox mind-set, were adhering to a flat earth theory.  Justice Windeyer went on:

"The most that could be urged against Dr Haines' evidence is that the cause of leukemia is not, in a positive sense, known, and that his view is thus unproven and not accepted by others, not that it can be scientifically established as false".

          In the end, the majority of the High Court concluded that it was not for judges to choose between the competing schools of scientific opinion put before the jury in that case by witnesses who, after all, were (without exception) lawfully qualified in the discipline involved.  Because the case had not been heard by a judge sitting alone, there were no expressed reasons for the preference of the jury for Dr Haines' evidence over that of Sir William Morrow and other experts called by the defendant.  The issue thus came down to whether there was any evidence before the jury that sustained Dr Haines' opinion.  The High Court majority held that there was.

          Inevitably, expert evidence will vary in accordance with the "present state of knowledge"^[15.  According to Justice Windeyer, the proper approach in such a case was^[16:

"The jury could consider whether [Dr Haines'] opinion was honestly held.  It was for them to consider whether, as counsel suggests, he was a charlatan.  They might think so or they might regard him as an earnest but misguided proponent of an incorrect theory or as a discoverer and prophet or in some other way".

          The majority rejected the defendant's challenge to the jury's verdict.  There was some evidence before the jury that a probable link existed between trauma and death.  In law, that was enough. Justice Taylor came to the contrary conclusion^[17:

"… [Dr Haines'] evidence was of no value whatever in the case and … it fails to provide any ground for finding that the deceased's leukemia resulted from a disturbance of his hypothalmic activity rather than from some other cause.  There was no other evidence in the case which suggested that any such disturbance took place and, accordingly, it is clear that the opinion initially expressed by Dr Haines was based upon an assumed set of facts of which there was no proof at the trial".

          It would be interesting to know whether advances in knowledge about the aetiology of leukemia in the forty years since Adamcik's case, supports the conclusion of Dr Haines or of the distinguished experts ranged against him.  His theory of "autonomic dyspraxia" might not have been embraced by medical science.  But his view that physical trauma and consequent emotional disturbances could sometimes trigger various forms of malignant processes might be supported today by majority expert opinion in the discipline.  On such questions of expertise there is often no final and uncontestable opinion.

          In Adamcik, all of the judges involved were mercifully spared the obligation to decide the issue for themselves and to give reasons for their decision.  However, in the intervening forty years, in most parts of Australia, civil jury trial of such cases has largely been abolished^[18.  Even in criminal matters, disputed questions that once were invariably determined by juries are now increasingly brought before judicial officers sitting alone.  In Australia, such persons are obliged to give reasons for all important determinations^[19.  These trends have meant that, the ability of our legal system to commit disputes about expert evidence to the enigmatic jury, as often as was possible in the past, has been lost.  Accordingly, judicial officers must understand the technicalities of the clash of scientific evidence.  They must do so sufficiently to be able to give convincing reasons for preferring one conclusion over another.

          These are the main reasons why the issue of expert evidence is not only an increasingly puzzling one, by virtue of the growing complexity of the evidence itself.  It is an increasingly important one, by virtue of the shift in decision-making towards imposing the duty on individual judges and magistrates to decide, and explain, how and why they have decided as they have.

THE 2001 MAGISTRATES' SURVEY

          It is in this context that the comparative study of the views of Australian magistrates on expert evidence becomes important.  At the time it was conducted in 1998, there were 401 Australian magistrates.  Their numbers have lately been increased by the creation of the Federal Magistrates' Service.  The survey investigated the experience of these judicial officers in the presentation of expert evidence in civil and criminal trials.

          Given the huge volume and great diversity of work that is performed by this branch of the Australian judiciary, the survey invited responses that would reflect a large measure of judicial experience and opinions based on that experience.  Remarkably, 203 of the then magistrates, or 50.62% of the Australian magistracy, responded.  I say remarkably because a response was not obligatory.  Somehow, it had to be squeezed into the enormous workloads that are imposed upon all sections of the magistracy.  The return was approximately the same as that earlier provided by the companion judicial survey in which 244 of the 478 trial judges of Australia (or 51.05%) had responded^[20.

          An interesting feature of the work of magistrates is that, more commonly than judges, they are sometimes obliged by their duties to perform quasi-inquisitorial functions, as in fulfilling the tasks of the oldest judicial office in the English-speaking world, the coroner, and in children's and juvenile courts and specialist tribunals where protective obligations are imposed on the Bench.  As well, the magistrate's survey was conducted after the coming into force of the Evidence Act 1995 (Cth) and (NSW).  The survey of the judiciary had been conducted before the uniform Evidence Acts were implemented.

          It might be said that the type of person who responds to surveys of this kind, amidst other duties, is somewhat more engaged in the intellectual issues than the non-respondents may be.  But making all due allowance for such considerations, the opinions of the authors of the survey was that, as with the judicial response, the  magistrates' return was accurate and representative.

          I will not recount all of the results of the survey.  But I agree with the authors that the results explode the myth that judicial appointment and service are enough to convert a lay person, inexpert in scientific and technological disciplines, overnight into a highly perceptive and informed decision-maker, able in every case to determine accurately the true or preferable expert opinion from one that is more suspect.  On the contrary, as a result of the survey, it is clear that improvements are needed in relation to expert evidence and its evaluation in courts of law.  Such improvements would include:

§                    Training of judicial officers in approaches to such problems and in the rudiments affecting commonly recurring scientific and technological issues;

§                    Improvements in the skills of advocates, including greater time in preparation for, and improved capacity in the presentation of, the evidence-in-chief of experts and in cross-examining them on their testimony;

§                    Education for the experts themselves, so that they will express their opinions in ways that avoid unintelligible technicalities, jargon or partisan rhetoric;

§                    Use of improved technologies of presentation of data for explaining and illustrating scientific and technological evidence; and

§                    Introduction of improved means of ensuring, so far as possible, the equality of arms in access to expertise that will ensure that the parties and the court will be able to render expert opinions, adduced in a trial, truly accountable to the law so that areas of expertise will be clarified and proffered expert opinion put under real scrutiny, and not simply accepted as gospel.

          Earlier investigations overseas have shown that the problem of partisan experts is not confined to Australian courts.  Lord Woolf, in his investigation of judicial process in England, had mentioned the growing judicial concern about the loss of independence and impartiality on the part of experts^[21.  In referring to this phenomenon, I am not, of course, overlooking a natural (and probably unavoidable) tendency of any expert, to some extent, to view the problem to be solved through the eyes of the party that first presented the problem and then called the expert to court to give evidence as to its solution.  To some extent, such a variation from Platonic notions of perfect impartiality has to be tolerated in any system of adversarial or accusatorial justice.  The two lists of physicians, having expertise in cardiac aetiology indicates that there is a measure of innocent partiality that the law acknowledges and allows for.

          But this is not the concern that is expressed in the magistrates' survey.  In fact, amongst the items in the performance of expert witnesses of which the magistrates of Australia complained most vigorously, the chief of these (29%) was bias on the part of the expert^[22.  Next in importance was the obscurity of the language of expert evidence (19%).  Equal to this was poor cross-examination of expert witnesses by advocates who failed to test their testimony as the magistrate thought would be necessary and helpful (19%).  Next in importance was the poor preparation of the advocate calling the expert witness and leading him or her through evidence by examination-in-chief (9%).  Of equal concern was the tendency of some experts to exceed their proved qualifications, perhaps in pursuit of justification of their conclusion and support for the party who called them (9%).  The final chief problem in this list was the failure of those calling expert witnesses to establish the factual foundation properly for the opinions that the experts proffered.  It is clear law, repeatedly stated by the High Court, that an expert opinion, based upon factual premises, depends for its acceptability (and usually admissibility) upon proof of those premises by admissible evidence^[23.

          It is important to note that, in their survey responses, the magistrates were not so much concerned about any risk that the expert was usurping their judicial function.  Nor were the majority anxious that they felt incompetent to resolve clashes of experts in highly technical areas.  Judicial officers know that someone has to do this.  Their resolution may not always be perfect; but it will be made and explained and will thereby discharge the public and social function of the courts.  Subject to appeal or review, it will, virtually invariably, quell the controversy.  Nor was a major focus of concern proof that particular witnesses had relevant expertise in the subject matter before the court.  The problem of Dr Haines and his autonomic dyspraxia theory has not lately loomed large in the day to day work of Australian courts.  But the increasing complexity and technicality of evidence about information technology and biotechnology makes it likely that some species of expertise will exist that will produce challenges to the competence, and entitlement, of a person claiming expertise to offer his or her opinion.

          Put bluntly, most of the concerns revealed in the Australian magistrates' survey relate to the very proper demand which the magistrates felt that they should not simply accept opinions (including from one side or the other) in a contested case simply because the person expressing that opinion had a proved expertise or qualification.  Life in the courts makes one sceptical and demanding about data.  It teaches the need for scrutiny, even of apparently honest and well intended evidence, in the knowledge that honest and well intended witnesses can sometimes make serious mistakes with grave personal and economic consequences.  It is a reassuring feature of the magistrates' survey that an analysis of the most serious problems which the magistrates identified concerning expert evidence suggests that they are all related to the deeply felt need of these judicial officers to ensure that such evidence could be safely accepted and adopted as part of their reasoning process towards the conclusion in a case.  In so far as the judicial officer suspects that the expert may be impermissibly biased; may not have been led accurately and properly through the basic evidence; may not have been helped or encouraged to express that evidence in language that will truly be understood; and may not have been tested by carefully prepared, knowledgeable and informed cross-examination, the resulting outcomes will be unsatisfactory.  It could even lead to an unintended injustice.

          When asked to identify the three factors that made the greatest impression in an expert witness, the Australian magistrates, in proportions virtually identical to Australia's judges and to similar surveys in the United States^[24 nominated (1) clear expression and explanation on the part of the expert; (2) demonstration that the expert had appropriate practical experience upon which to base the opinion; and (3) perceived impartiality in the presentation of the opinion. 

IMPROVING FORENSIC EVIDENCE

          From the survey of the Australian judiciary at all levels, there emerges a consistent expression of opinion that the advance in scientific and technological complexity, and the growing importance of such evidence in criminal and civil trials (together with perceptions of the imperfection of the current presentation of such evidence), require the implementation of reforms that will help improve the performance of the courts in deciding cases involving conflicting expert testimony.  Amongst the improvements that have been proposed are:

§                    The institution of court approved lists of experts, including experts of recognised experience and integrity, who have diverse opinions about contentious questions likely to arise in litigation;

§                    The provision of effective appellate scrutiny of trial preference for one expert opinion over another.  In this respect, the defects of basing conclusions on impressions of credibility, derived from the appearance of expert witnesses may need review, being even more unsatisfactory in such cases than similar differentiation in the case of lay witnesses^[25;

§                    The introduction of court rules, obliging the exchange of expert reports well in advance of the hearing and, possibly, the identification of all experts consulted (including those whose evidence may not be adduced in the trial);

§                    The introduction of procedures to permit a more informal oral interaction between expert witnesses themselves, so far as this is compatible with Australian constitutional norms and notions of fair trial.  The Federal Court of Australia^[26 has experimented with this form of exchange, which obviously has its own dangers and weaknesses but may sometimes allow a more effective clarification of the precise points of difference and agreement, when compared to the seriatim provision of expert testimony, often interposed between other evidence to suit the convenience of the experts;

§                    The introduction of a "declaration" or "special oath" which an expert, called to give evidence in a case is required to acknowledge in a formal manner.  The authors of the magistrates' survey proposed a somewhat wordy declaration.  The essence (by no means the whole) of it provides^[27:

"I declare that:

(1)I recognise that my overriding duty … is to the court, rather than to the party commissioning me and/or paying my fees.

(2)I have used my best endeavours to produce my report in sufficient time to enable proper consideration of it.

(3)I have made myself reasonably available for discussion of the contents … with professional representatives of all parties …

(4)I have provided with my report details of … qualifications/literature/co-compilers/instructions received.

(5)I have used my best endeavours, and will endeavour in any evidence that I am called to give,

(a)to confine myself … [to] those areas in which I am specially knowledgeable;

(b)to distinguish among the data … the assumptions that I have employed and the opinions at which I have arrived;

(c)to indicate those data … upon which I have significantly arrived;

(d)to give succinct reasons for each of the opinions which I express;

(e)to be objective and unbiased;

(f)to make the opinions which I express clear, comprehensible and accessible to those not expert in my discipline;

(g)to be scrupulous in terms of accuracy and care in relation to the data upon which I rely …

(h)to indicate whether I have been provided with all the data necessary …

(i)to indicate whether I have been appraised of any data … inconsistent with the opinions which I have expressed; and

(j)to indicate whether I have been unable for any reason to employ the methodology which I would prefer to use before expressing an opinion.

(6)If I become aware of any error … I will … notify those who have commissioned my report or called me to give evidence;

(7)I will use my best endeavours to ensure that my opinions and data are not misunderstood or misinterpreted by the court;

(8)I have not entered into any arrangement which makes the fees to which I am entitled dependant upon the views I express or the outcome of the case in which my report is used or in which I give evidence".

          Some of the foregoing proposals for reform would not be appropriate to the accusatorial criminal trial.  In Australia and other common law countries that form of trial is conducted in accordance with special rules.  The criminal trial does not proceed, at least normally, upon the principles of adversarial litigation.  It is a peculiar form of trial in which the prosecution must prove its case against the accused beyond reasonable doubt.  Ordinarily, the accused need prove nothing.  The High Court has had reason, in a number of recent cases, to lay emphasis upon this foundational principle of the criminal trial system in Australia^[28.  Without statutory authority, that principle must not be overlooked, even in well-intended endeavours to ensure that expert evidence is more accurate, understandable and accountable.

          Because of the explosion of scientific and technological data, and the sub-species of expertise that grows up as a consequence, it will probably soon be necessary for the High Court to examine the precondition to expertise that authorises a person, claiming to be an expert, to state an opinion in formal judicial proceedings.  In so far as this topic is affected by legislation, the legislation must be obeyed.  But otherwise, the developments of the common law in overseas jurisdictions present potential criteria that we in Australia might also consider.

          In Daubert v Merrell Dow Pharmaceuticals^[29, the Supreme Court of the United States suggested four tests for the reliability of expert testimony essential to its reception in a trial:

(1)        Whether the theory or technique can be or has been tested - is it falsifiable, refutable or testable?;

(2)        Whether the theory or technique has been subjected to peer review and publication as a means of increasing the likelihood that substantive flaws in methodology will be detected;

(3)        Whether the known or potential error rate is acceptable and whether standards exist and are maintained controlling the technique's operation; and

(4)        Whether the technique or theory has gained general acceptance within the relevant scientific community.

          The foregoing tests have proved controversial in the United States^[30.  Before their adoption in Australia, they would need consideration in the light of discussion that has followed their promulgation in the United States.  Moreover, the tests would need evaluation in the context of the Australian legal system which, as the Adamcik case demonstrates, has been willing to allow tribunals of fact a certain leeway in judging the existence of relevant expertise and has been somewhat resistant to excessive dependance upon legal enforcement of the standards of professional orthodoxy^[31.  Perhaps these features of Australian scepticism, like the tall poppy syndrome, derive from our early days as convict settlements and the high level of questioning that exists in this country towards authority, whether public, professional, scientific or anything else.

CONCLUSIONS

          The magistrates' survey on expert evidence shows just how far we have come in examining questions of this kind.  The use of judicial surveys is not new.  In the Australian Law Reform Commission's 1980 report on sentencing of federal offenders^[32, the Commission undertook a major survey of judicial opinions about aspects of sentencing.  The results then gave a unique insight into the opinion of judges and magistrates of that time about the controversies of sentencing, most of which have not disappeared.  The magistrates and judges invited to participate were individually requested to take part.  Even on that occasion 231 magistrates responded, an indication of the abiding conscientiousness of magistrates who then, as now, carried the heaviest load of criminal dispositions in Australia.

          In some ways the questions asked in the more recent expert evidence survey were more searching and complex, the issues being more particular and, in part, more opaque.  The returns by the Australian magistracy demonstrate the strongly felt need to improve the performance of Australian courts in the evaluation of the acceptability of expert evidence.  And the need that judicial officers of every rank feel that the presentation of expert evidence by expert witnesses, and through the advocates who call them and cross-examine them, needs to be improved if the courts' performance is to be maintained at a high level in the contemporary scientific environment and if the expert evidence is to be properly tested and scrutinised as it should be.

          These conclusions teach the need for improved training of judicial officers; improved preparation by advocates; improved presentation of expert testimony by witnesses; improved court rules and improved techniques for subjecting experts to proper, searching examination.

          Because decisions affecting individual liberty in the future will increasingly depend upon DNA evidence gathered by police rather than mere confessions and because civil entitlements will increasingly depend upon the evidence of experts (scientific, legal, accounting and otherwise), the judiciary and the legal profession (as well as experts themselves) must enhance the means of rendering experts understandable and accountable in the public courts of law.  This is why the magistrates' (and earlier the judges') surveys on expert evidence are so important.  It is also why the ongoing work of judicial and professional education, including in the International Institute of Forensic Studies and the Australian Advocacy Institute, are vital for the health of the rule of law and the proper discharge by our courts of their increasingly challenging and onerous duties when highly complex technological evidence is tendered in a contested case.

THE JUDICIAL REVIEW

EXPERT EVIDENCE:  CAUSATION, PROOF AND PRESENTATION

The Hon Justice Michael Kirby AC CMG

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