GUEST EDITORIAL 0 Forensic Science Society 1987

Forensic science and the justice system in the late twentieth century

JAJ FERRIS

Department of Pathology, University of British Columbia, 2211 Westbrook Mall, Vancouver, BC, Canada V6T 1WS

The historical evolution of the forensic sciences, with the formation of multiple sub-specialities including almost every subject known to man capable of supporting the designation science, has in large part been dictated by the evolution of science itself. At the turn of the century, it became apparent that contemporary scientific techniques could be used to support the police in their criminal investigative roles. Until that time the principal scientific input into crime investigation had been from university departments of forensic medicine and pathology, but it soon became apparint .that almost all branches of the newly developing scientific revolution could be applied to the field of crime investigation. The general philosophy that appeared to develop, and is still with us today, is that any scientific technique which can be applied to such work can be absorbed into this new, ever-expanding community of forensic sciences.

As we approach the end of the twentieth century, the increasing rate of discovery in basic biology, bio-engineering and computer science, has inundated the forensic community with a wide array of technical innova- tions. Because of the improved systems of communication and public education provided by all forms of media, the general public and the courts are aware of these technical advances and consequently the public and the judicial system demand a second to none forensic science service that takes full advantage of every new expensive technology. How is it going to be possible to fulfil these expectations in the face of continuing limitations on funds and resources?

It is apparent that the only way to reconcile these rising expectations for forensic science services within the limited resources available is by collaboration between laboratory professionals in all fields of forensic science in the cost-effective use of laboratory facilities.

It is difficult at present to persuade new graduates from universities to accept standards of pay and promotion no longer comparable with industry. If we are unable to offer such new recruits an opportunity to take part in innovative research and development, they will be rapidly disillusioned and flee the system. The immediate consequence of this will be a reduction in standards of scientific evidence and a rapid realization that forensic science

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has become no more than a second-class laboratory support system presenting barely credible evidence in court. I would suggest that the general morale in the forensic community is already suffering as a direct consequence of budget cut-backs on training and recruitment.

How to maintain a high quality of forensic laboratory service in the face of constraints on funding will continue to be a critical issue until the end of this century. One obvious approach is to pool professional and technological resources into larger laboratory communities. It is apparent, however, if we look at the funding support available to the various branches of forensic science and forensic pathology, that the direct budgets available to the traditional forensic science laboratories far exceed those available to areas such as my own, namely forensic pathology. However, if we look beyond these traditional budgets and barriers, and see that the forensic pathology community invariably operates as part of large university-based clinical laboratories, and if we consider forensic pathology as simply representing a division of the whole field of laboratory medicine, a comparison of the relative financial resources available to the forensic pathologist and non- medical forensic scientists shows a significantly altered fiscal picture.

For example, in the city of Vancouver in British Columbia there are four principal hospitals associated with the University of British Columbia. The hospital at which I am based, Vancouver General Hospital, used to be the largest hospital in Canada and is one of the largest hospitals in the Commonwealth. Today, as a result of specialization in some areas of clinical medicine and decentralization in others, this hospital, in terms of its overall size, has lost some of its past glory but not its reputation.

Our University Department of Pathology Chairman oversees not only the operation of this huge department but also all of the academic and research activities involving the whole of laboratory medicine in this hospital group. The laboratory budget for Vancouver General Hospital is approximately $15 million CAD but the laboratory budget for the entire group is approximately $40 million. In addition to this direct funding, over $6 million of research grant money is placed on an annual basis at the disposal of the laboratory staff. Since most of the pathologists in the group have university appointments and since these hospitals have a long traditional association with the university, there is a general understanding that up to 25% of the time of all members of the University Department of Pathology may be devoted to academic pursuits. This means that not only is there a $6 million research budget directly funded, but there is an additional "hidden component" of $4 million applied directly to research and development funded through the health care budget.

Working within this large department of pathology with its own specialty laboratories whose location is dictated only by logistical convenience, I can

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draw upon almost any resource component of this network to support the activities of my forensic pathology service. Comparing this with the problems associated with funding of forensic laboratory services, which are administered and directed by government, who invariably find themselves working in isolation from the rest of the scientific community, one can rapidly see that not only is there a technical resource advantage to a university-based forensic science service, but the financial resource potential is very considerable indeed.

It is misleading, however, to suggest that such apparent disparities in budgets for research and development between medical laboratories and forensic science laboratories occur only in Canada. I would suggest to you that such differences in funding are typical throughout the Western world. Consider, however, the very great shortfall in funding not only for research and development but for routine forensic sciences in the Third World where governments everywhere are attempting to divert what funds they have available to them to health care. It is a political fact of life that health care will always take priority over the forensic sciences for funds. If we can accept this and learn to live with it, the solution to some of our budgetary problems for the human, biological and toxicological aspects of forensic sciences may become more apparent.

At present the forensic science laboratory services can be divided into several distinct groups. Much of forensic biology is human biology; toxicology is really a form of laboratory-based applied pharmacology; forensic serology and immunology, which in many laboratories are now distinct from forensic biology, are unashamedly direct developments from laboratory medicine.

No one would suggest that the nature of the samples submitted to forensic science laboratories is in any way directly comparable to the type of material routinely investigated in a medical laboratory. Nevertheless, the problems in the area of body fluid and body fluid stain examination are relatively constant, namely, sample deterioration with age, sample size, drying, distortion and decomposition. There is no real reason, however, why the particular problems associated with forensic science field work cannot be applied at an early stage during the research and development of a new clinical technique. There is no reason why medical research laboratories could not be developing forensic procedures in parallel with the procedures required for patient care and diagnosis.

The ELISA technique as it develops in forensic immunology offers an opportunity to add an invaluable parameter to the area of body fluid identification. The major disadvantage, however, seems to be the cost of purchasing fully-automated equipment such as dispensers and spectrophoto- meters. Although some success has been demonstrated with manual

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techniques, such automated procedures, if available, are going to allow for the more cost-effective use of immunoglobulin allo-typing. Such automated equipment is available in many clinical hospital laboratories.

In the area of forensic toxicology, the pattern of work of the forensic toxicologist is often dictated by the pressures of the judicial system. Most forensic toxicology laboratories are concerned primarily with the detection of crime by the identification of restricted drugs or by the identification of toxic or fatal levels of drugs. Coroners, however, involved in the investiga- tion of death and, in particular, in the investigation of human factors associated with unnatural deaths, may not be directly concerned with the identification either of restricted drugs or toxic levels of drugs. It may become important to identify drugs at therapeutic or below therapeutic levels. Many forensic toxicology laboratories are unwilling, or unwilling to take the time, to analyze for drugs in concentrations that may have no criminal significance.

In my own area in British Columbia, the segregation of forensic toxicology services into criminal and non-criminal is now almost complete. The Royal Canadian Mounted Police (RCMP) Crime Laboratory is concerned almost exclusively with toxicology tests as part of an investigation of criminal activity. The British Columbia Coroners Service, however, requires an extensive and speedy toxicology service. As a result, a separate provincial forensic science laboratory has been established, funded directly by the Coroners' Office, with the resulting duplication in equipment and staffing, and the attendant problems of quality control associated with any division of responsibilities.

The Department of Clinical Toxicology at Vancouver General Hospital is one of the largest and best-equipped toxicology laboratories in the country and yet its responsibility is almost exclusively in the area of clinical toxicology, research and development. Each of the laboratories considers itself expert and of course, the quality of results produced by the laboratories is comparable.

Unfortunately, quality of service is often assessed by the consumer, usually the police and courts, not on the basis of accuracy or reproducibility of results, but on the rapidity with which results are produced. For example, the average turnaround time for toxicological screening in the RCMP Crime Laboratory is 6 weeks. The average turnaround time in the Coroners' toxicology laboratory is 10-14 days. The average turnaround time for toxicological screening in the hospital toxicology laboratory is 6 hours for a preliminary result with a full final follow-up report within 12-24 hours of the sample being received.

The reasons for the significant disparity in turnaround time between these three laboratory services is a reflection, not of the quality of staff or

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equipment, but of a combination of the pressures and expectations of their role, and therefore directly reflects the overall budgeting. No forensic toxicologist will deny that with adequate financing he would be unable to compete in terms of turnaround time and quality with any clinical laboratory anywhere in the world. However, realistically, this funding is not available and will not be available.

Disparity in funding for research and development is becoming such a critical issue that important techniques are not being developed with the vigor that our courts and criminal investigative systems could reasonably expect. I would like to illustrate this point by giving the particular example of the application of DNA fingerprinting to forensic sciences.

The use of DNA analysis will revolutionize identification procedures in forensic immunology resulting in certainty as to the origin of tissue, provided material from a suspected source is available for comparison purposes. In the past twelve months, a series of papers have appeared in which a simple Southern blot technique has allowed for the positive identification of blood samples using a variety of human DNA probes. Jeffreys and colleagues have calculated that the probability of DNA fragments from any two unrelated individuals being identical when a two enzyme and probe system is used is considerably less than 5 x 10-19. These techniques have recently withstood the rigors of the British legal system and were upheld as valid in a case of disputed paternity.

Clearly, the next step is to apply these procedures to the identification of body fluid stains. We in Vancouver have outlined a simple DNA dot blot technique to differentiate human males and females, as well as humans from other animals, by the examination of dried bloodstains of varying ages. This work was performed in the Molecular Probe Laboratory in the University Department of Pathology in Vancouver where a wide variety of probes are routinely being used to assist with the identification of genetic abnormalities in children.

In order to develop independently a single DNA laboratory, the forensic science community would be required to invest approximately $250,000 US in equipment and facilities alone. Such a laboratory would require minimum staffing by two technologists specially trained in these procedures, since once an analysis has been initiated, it cannot be stopped halfway to allow for holidays or sick leave. In Vancouver, we have identified the cost of sharing this laboratory with a research and development program for forensic science. We have decided to develop a forensic science DNA fingerprint laboratory in conjunction with our existing hospital molecular probe laboratory and have recently received a research grant of $64,000 from the Attorney General in British Columbia and from the British Columbia Law Foundation to establish such a joint laboratory. Clearly, the

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satisfactory development of a DNA fingerprint laboratory in forensic science can most effectively and efficiently be done in conjunction with existing medical laboratories on the basis of sharing of facilities, training and existing knowledge.

I believe that the re-integration of laboratory services within forensic science and, in particular, the re-integration of medical laboratory services can be only to the long term advantage of the science of crime investigation. The technical and administrative problems associated with such a re- orientation of thinking are not insurmountable. The basic problems are the biases that have developed between the medical and non-medical branches of forensic science.

The traditional view is that forensic science conducted within a medical laboratory setting must be under the control of the forensic pathologist. This is not true. Forensic pathologists, in their efforts to find kudos and status, have insisted on financial and administrative independence from other branches of laboratory medicine and, as a result, they have found themselves isolated and deprived of funding. The forensic pathologist must also integrate himself with his clinical laboratory colleagues. Status is not achieved by independence. Reputation is based on quality of work.

The problems of the reintegration of forensic sciences have to be measured against the super-specialization that is occurring within all branches of forensic science. The current conflict within forensic sciences is that the technical expertise required to give evidence in court is such that it is almost impossible for the expert witness to have an overall comprehension of the relevance of his own particular area of expertise.

Opinion evidence, because of its special status within an adversarial judicial system, must be accepted with caution. The areas of expertise of the witness must be clearly defined. For example, forensic pathologists are expert in the interpretation of injuries, injury mechanisms and causes of death, both natural and unnatural. Bloodstain pattern analysis is an area of expertise in which most pathologists, and many forensic pathologists, have no training and have made no particular study. The opinions that they may express in this area may be on the basis of individual case experience rather than careful objective study. Such opinions are likely to be determined by what the expert may expect to happen, based on his understanding of basic principles, and not upon what he knows to happen, based on knowledge and experience. Any super-specialization must result in a narrowed area of expertise for the witness in court. This means that the scope of the opinion evidence witness has to be very clearly defined and limited to his own area of knowledge.

It is important, therefore, that the opinions expressed in court under the qualification of expert should be confined to the area of proven expertise,

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and that other opinions should be subjected to limited or very specific qualification. Without such witness control, the special privileges of the expert opinion witness may be abused and the court may be misled by opinions which fall short of the usual judicial standards associated with the qualified expert. It must always be remembered that titles, status or degrees should not allow an opinion witness to stray beyond his area of proven expertise.

Opinion evidence is dependent upon the reliability of observations and the accuracy, validity and relevance of evidence tested. Often the quality of evidence submitted to the expert for analysis is questionable. It is important that the expert should not be held responsible for the quality or integrity of evidence that he or she has not been responsible for collecting and selecting. Opinions are based on evidence available and such a basis should be clearly defined. The expert must be allowed the right to modify and change opinions if further evidence becomes available or if the reliability of certain evidence is subsequently questioned.

Tests performed by any particular expert are subject to certain standards of proof, and even in the most exact areas of forensic science, no conclusions can be considered absolute. Forensic experts, experienced in the require- ments and expectations of a particular judicial system, accept that standards of proof are measured in degrees of probability based on personal knowledge, training and experience. Numerical or statistical evaluations of such standards of proof may be either inappropriate or misleading when applied to expert opinions. Within the context of forensic science, qualita- tive tests performed by experienced scientists may have greater probative relevance than quantitative tests with their apparent, rather than real, reliability.

Reasonable doubt should not be measured in terms of statistical probabili- ties. Such numerical values may be inappropriate in determining reasonable doubt. If a particular standard of proof is required, it is for the court to advise the expert of this standard and ask him if his opinions and conclusions fall within, these, the court's, standards. The inexperienced expert must be made aware of these standards of proof, otherwise reasonable doubt may be equated with any standards short of absolute proof or conversely may be measured in terms of balance of probabilities. Clearly, this is exactly the sort of problem that may occur when the super-specialist with his relatively limited court experience may be unfamil- iar with the requirements of opinion evidence in civil or judicial proceedings and unless the terms of his evidence are clearly defined for him, significant confusion may arise.

I have heard it stated on a number of occasions in court that one can never draw a positive conclusion from a negative result. This statement, which is

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an apparent scientific truism, in the context of a criminal trial is fundamen- tally incorrect. It all depends upon the expectations of the results of a test. For example, a negative test for blood may mean either that no blood was present or that the procedure was incorrect. If it can be shown by parallel control tests that the procedure was correct, then a negative result can be reasonably considered to mean that blood was not present within the limits of that particular examination.

All scientific tests have defined limits of sensitivity, accuracy and re- producibility but this does not mean that a particular test is invalid or wrong because of these limitations. Similarly, experiments performed to test a particular hypothesis must be relevant to the theory being tested and any departures from this theory must be compensated for or explained. Any particular part of scientific evidence can be contested. However, it is the competence and experience of the scientist as an expert forensic witness that is the best measure of the real value of the opinion.

Clearly, then, one of the greatest problems confronting forensic science and the presentation of expert evidence in court is the training of the judicial system to understand the limitations and relevance of scientific evidence and the training of the forensic scientist to understand the requirements of the judicial system. If super-specialization within the forensic sciences is a fact of life, and I believe it is, the best ,way to overcome the problems and to improve the education and knowledge base of these super-experts is to have large integrated laboratories where individuals are aware of the areas of expertise of their colleagues and have frequent forums where they have an opportunity to hear and discuss the problems encountered by other forensic scientists in areas which they themselves may have no special experience.

Earlier I highlighted the importance of the reintegration of medical and non-medical forensic sciences. However, it may be that all of us, within the field of forensic science and medicine, because of our inherent biases, can no longer be completely objective and are perhaps not the best people to determine our own future. When it comes to a question of introducing a new technology in forensic science, perhaps such projects should be studied by a multi-disciplinary group including representatives of the judicial system, the police, forensic science, universities and the private sector. Decisions should be made with the full awareness of resource implications, department goals and the complex needs that the technicological advances must serve.

It is perhaps not wrong to relate cost benefit analysis to demands for capital equipment in a system that is not a revenue generator, but is subject to global budgeting. Efficient forensic laboratory services in the next few years must implement technicological changes by cost effective means. This may involve some reorientation of laboratory services, some decentralization of

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research and development and a sharing of expertise that cross traditional scientific boundaries.

Acknowledgement This paper has been abbreviated from the presentation made at the 56th meeting of the Australian and New Zealand Association for the Advancement of Science, Palmerston North, New Zealand, in January 1987.