FPT HEADS OF PROSECUTIONS COMMITTEE
REPORT OF THE WORKING GROUP ON THE PREVENTION OF MISCARRIAGES OF JUSTICE

9. FORENSIC EVIDENCE AND EXPERT TESTIMONY


9. FORENSIC EVIDENCE AND EXPERT TESTIMONY

I. INTRODUCTION

Properly qualified and admissible expert testimony can be powerful evidence. It can identify a potential suspect to the exclusion of all others. It is a significant assistance to the trier of fact in appreciating specific facts and circumstances in a prosecution that are outside of its general knowledge and understanding. On the other hand, tainted, tailored and unsubstantiated expert evidence, couched in scientific terms and language, based on unreliable fact and ultimately debunked science has long been recognized as a leading cause of wrongful convictions.[207] Following on the heels of recent public inquiries, judicial pronouncements and interventions by advocacy groups, the current trend is:

  • The admission of expert evidence depends on its relevance to a fact in issue, the necessity to assist the trier of fact on exceptional issues that require special knowledge outside their normal experience, the absence of any exclusionary rules and the proper qualifications of the expert;
  • Judges maintain their duty as “gatekeepers” to prevent the distortion of the fact-finding process by excluding the admission of inappropriate and unnecessary expert testimony;
  • The ultimate role of the trier of fact is not to be usurped by expert evidence;
  • Appropriate and non-misleading language be used in reporting forensic conclusions; and
  • Forensic evaluation services no longer be the exclusive domain of the state.

Expert evidence has traditionally been admitted as an exception to the rule against opinion evidence, to assist the trier of fact to understand and rule on complex and technical issues that may be above the general level of knowledge. The basic underlying premise of expert scientific evidence is that the opinion to be considered by the trier of fact given by someone with special knowledge and training is the result of disinterested, objective and scientifically sound reasoning. However, some expert opinions can present difficulties to the trial process. Sometimes, it appears the experts are not terribly impartial. Some are far from expert. On occasion, their evidence may be seen as virtually infallible, having more weight than it deserves, with the result that the evidence distorts the normal fact-finding process at trial. Finally, sometimes objective sciences such as DNA later show that the opinions tendered in evidence were simply wrong.[208]

II. CANADIAN COMMISSIONS OF INQUIRY

Among the primary focuses of the Morin and Sophonow Inquiries were the mishandling and improper testing of forensic evidence, reliance on unreliable scientific data and the tainted expert opinion testimony.

a) The Commission on Proceedings Involving Guy Paul Morin

Recommendation 2 - Admissibility of hair comparison evidence

Trial judges should undertake a more critical analysis of the admissibility of hair comparison evidence as circumstantial evidence of guilt. Evidence that shows only that an accused cannot be excluded as the donor of an unknown hair (or only that an accused may or may not have been the donor) is unlikely to have sufficient probative value to justify its reception at a criminal trial as circumstantial evidence of guilt.

Recommendation 3 - Admissibility of fibre comparison evidence

Evidence of forensic fibre comparisons may or may not have sufficient probative value to justify its reception at a criminal trial as circumstantial evidence of the accused's guilt. However, the limitations upon the inferences to be reliably drawn from forensic fibre comparisons need be better appreciated by judges, police, Crown and defence counsel. This requires better education of all parties, improved communication of forensic evidence and its limitations in and out of court, in written reports and orally.

Recommendation 4 - Admissibility of preliminary tests as evidence of guilt

Evidence of a preliminary test, such as an ‘indication of blood,' does not have sufficient probative value to justify its reception at a criminal trial as circumstantial evidence of guilt.

Recommendation 5 - Trial judge's instructions on science

Where hair and fibre comparison evidence or other scientific evidence is tendered as evidence of guilt, the trial judge would be well advised to instruct the jury not to be overwhelmed by any aura of scientific authority or infallibility associated with the evidence and to clearly articulate for the jury the limitations upon the findings made by the experts. In the context of scientific evidence, it is of particular importance that the trial judge ensure that counsel, when addressing the jury, do not misuse the evidence, but present it to the Court with no more and no less than its legitimate force and effect.

Recommendation 6 - Forensic opinions to be acted upon only when in writing
  1. No police officer or Crown counsel should take action affecting an accused or a potential accused based upon representations made by a forensic scientist which are not recorded in writing, unless it is impracticable to await a written record. Where a written record is not obtained prior to such action, it should be obtained as soon thereafter as is practicable.
  2. The Crown Policy Manual and the Durham Regional Police Service operations manual should be amended to reflect this approach. The Ministry of the Solicitor General should facilitate the creation of a similar policy for all Ontario police forces.
  3. Where a written record is only obtained after such action, and it reveals that the authorities acted upon a misapprehension of the available forensic evidence, police and prosecutors should be mindful of their obligation to take corrective action, depending upon the original action taken. Corrective action would, for example, include the immediate disclosure of the written record to the defence and, if requested, to the Court, where the forensic evidence has been misrepresented (even inadvertently) in Court. It would also include the re-assessment of any actions done in reliance upon misapprehended evidence.
Recommendation 7 - Written policy for forensic reports

The Centre of Forensic Sciences (CFS) should establish a written policy on the form and content of reports issued by its analysts. The Centre should draw upon the work done by forensic agencies elsewhere and the input of other stakeholders in the administration of criminal justice who will be receiving and acting upon these reports. In addition to other essential components, these reports must contain the conclusions drawn from the forensic testing and the limitations to be placed upon those conclusions.

Recommendation 8 - The use of appropriate forensic language

The Centre of Forensic Sciences should endeavour to establish a policy for the use of certain uniform language which is not potentially misleading and which enhances understanding. This policy should draw upon the work done by forensic agencies or working groups elsewhere and the input of other stakeholders in the administration of criminal justice. This policy should be made public.

Recommendation 9 - Specific language to be avoided by forensic scientists

More specifically, certain language is demonstrably misleading in the context of certain forensic disciplines. The terms ‘match' and ‘consistent with' used in the context of forensic hair and fibre comparisons are examples of potentially misleading language. CFS employees should be instructed to avoid demonstrably misleading language.

Recommendation 10 - Specific language to be adopted

Certain language enhances understanding and more clearly reflects the limitations upon scientific findings. For example, some scientists state that an item ‘may or may not' have originated from a particular person or object. This language is preferable to a statement that an item ‘could have' originated from that person or object, not only because the limitations are clearer, but also because the same conclusion is expressed in more neutral terms.

Recommendation 11 - The scientific method

The ‘scientific method' means that scientists are to work to vigorously challenge or disprove a hypothesis, rather than to prove one. Forensic scientists at the Centre should be instructed to adopt this approach, particularly in connection with a hypothesis that a suspect or accused is forensically linked to the crime.

Recommendation 12 - Policy respecting correction of misinterpreted forensic evidence

A forensic scientist may leave the witness stand concerned that his or her evidence is being misinterpreted or that a misperception has been left about the conclusions which can be drawn or the limitations upon those conclusions. An obligation should be placed on the expert to ensure that these concerns are communicated as soon as possible to Crown or defence counsel. Where communicated to Crown counsel, an immediate disclosure obligation is triggered. The Crown Policy Manual and the Centre's policies should be amended to reflect these obligations. The Centre's employees should be trained to adhere to this policy.

Recommendation 13 - Policy respecting documentation of contacts with third parties
  1. The Centre of Forensic Sciences should establish a written policy requiring its analysts and technicians to record the substance of their contacts with police, prosecutors, defence counsel and non-Centre experts. This policy should regulate the form, content, preservation and storage of such records. Where such records are referable to the work done on a criminal case, they must be located within the file(s) respecting that criminal case (or their location clearly noted in that file).
  2. The Centre of Forensic Sciences should ensure that all employees are trained to comply with the recording policies.
Recommendation 14 - Policy respecting documentation of work performed
  1. The Centre of Forensic Sciences should establish written policies regulating the content of records kept by analysts and technicians of the work done at the Centre. In the least, these policies must ensure that the records identify the precise work done, when it was done, by whom it was done and the identity of any others who assisted, or were present as observers when the work was performed. The policy should also regulate the retention period and location of these records. All records referable to the work done on a criminal case must be located within the file(s) respecting that criminal case (or their location clearly noted in that file).
  2. The Centre of Forensic Sciences should ensure that all employees are trained to comply with the recording policies.
Recommendation 15 - Documentation of Contamination
  1. Where in-house contamination is discovered or suspected by the Centre of Forensic Sciences, the contamination should be fully investigated in a timely manner. The contamination and its investigation should be fully documented. A copy of such documentation should be placed in any case file to which the contamination may relate. The matter should immediately be brought to the attention of the Director, the Quality Assurance Unit and the relevant Crown counsel. The Centre's written policies should reflect these requirements.
  2. The Centre of Forensic Sciences should also reflect, in its written policies, the protocols to be followed by its employees to prevent the contamination of original evidence.
  3. The Centre of Forensic Sciences should ensure that its employees are regularly trained to comply with the policies reflected in this recommendation.
Recommendation 16 - Documentation of Lost Evidence

Where original evidence in the possession of the Centre of Forensic Sciences is lost, the loss should be fully investigated in a timely manner. The loss and its investigation should be fully documented. A copy of such documentation should be placed in any case file to which the original evidence relates. The matter should immediately be brought to the attention of the Director, the Quality Assurance Unit and the relevant Crown counsel. The Centre's written policies should reflect these requirements. In this context, original evidence extends to work notes, communication logs or other material which is subject to disclosure.

Recommendation 17 - Reciprocal disclosure

Reciprocal disclosure of expert evidence should be established. The defence should be obliged to disclose to the Crown in a timely manner the names of any expert witnesses it intends to call as witnesses, along with an outline of the witnesses' evidence.

Recommendation 18 - Joint education on forensic issues

The Centre of Forensic Sciences, the Criminal Lawyers' Association, the Ontario Crown Attorneys' Association and the Ministry of the Attorney General should establish some joint educational programming on forensic issues to enhance understanding of the forensic issues and better communication, liaison and understanding between the parties. The Government of Ontario should provide funding assistance to enable this programming.

Recommendation 19 - Creation of an Advisory Board to the Centre of Forensic Sciences

An advisory board to the Centre of Forensic Sciences should be established consisting of Crown and defence counsel, police, judiciary, scientists and laypersons. It should be created by statute.

Recommendation 20 - Quality Assurance Unit
  1. The recent establishment of a quality assurance unit by the Centre is to be commended. The unit's staffing and mandate should be reflected in written policies. Dedicated funds should be allocated to the quality assurance unit, adequate to implement this recommendation. The unit's budget should be insulated from erosion for operational use elsewhere.
  2. The unit should consist of at least seven full time members. The Centre should be encouraged to hire at least half of the unit's members from outside the Centre. At least one member of the unit should have training in biology.
  3. The unit should include a training officer, responsible for internal and external training.
  4. The unit should include a standards officer, responsible for writing, or overseeing the writing of policies.
Recommendation 21 - Protocols respecting complaints to the Centre of Forensic Sciences
  1. In consultation with the advisory board, the Centre should establish, through written protocols, a mechanism to respond to, investigate and act upon complaints or concerns expressed by the judiciary, Crown and defence counsel, or police officers. The protocols should identify the person(s) to whom a complaint or concern should be directed, how it should be investigated and by whom, to whom the results should be reported and what actions are available to the Centre at the conclusion of the process.
  2. Trial and appellate judges should be encouraged by the Centre, through correspondence directed to the Chief Justice of Ontario, the Chief Justice of the Ontario Court of Justice (General Division), and the Chief Judge of the Ontario Court of Justice (Provincial Division) to draw to the Director's attention, in writing, any concerns about testimony given by the Centre's scientists. Judges should be encouraged by the Centre to identify judgments, rulings or comments made by the Court in instructing the jury which are relevant in this regard. Transcripts should generally be obtained by the Centre of the relevant judicial comments, together with the witness' testimony.
  3. The Crown Policy Manual should be amended to provide that Crown counsel should draw to the Centre's attention such concerns, together with such particulars that will enable the matter to be investigated by the Centre. This policy should be encouraged through correspondence directed to the Ontario Crown Attorneys' Association.
  4. The private bar should be encouraged by the Centre, through correspondence directed to relevant organizations, including the Criminal Lawyers' Association and the Canadian Bar Association — Ontario, to draw to the Centre's attention such concerns, together with such particulars that will enable the matter to be investigated by the Centre.
  5. Police officers should be encouraged by the Centre, through correspondence directed to relevant police forces, or through the Ministry of the Solicitor General, to draw to the Centre's attention such concerns, together with such particulars that will enable the matter to be investigated by the Centre.
Recommendation 22 - Post-Trial Conferencing

The Centre of Forensic Sciences should establish a case conferencing process to assist in evaluating performance.

Recommendation 23 - Audits of the Centre of Forensic Sciences

The Centre of Forensic Sciences should, in consultation with its advisory board, engage an independent forensic scientist (or scientists) no later than October 1, 1998, to specifically evaluate the extent to which the failings identified by this Inquiry have been addressed and rectified by the Centre. The scientist's (or scientists') final report should be made public.

Recommendation 24 - Monitoring of Courtroom Testimony

The Centre of Forensic Sciences should more regularly monitor the courtroom testimony given by its employees. Monitoring should, where practicable, be done through personal attendance by peers or supervisors. Monitoring should exceed the minimum accreditation requirements. All scientists, regardless of seniority, should be monitored. Any concerns should be promptly taken up with the testifying scientist. The monitoring scientist should be instructed that any observed overstatement or misstatement of evidence triggers an immediate obligation to advise the appropriate trial counsel.

Recommendation 25 - Training of Centre of Forensic Sciences employees

The Centre of Forensic Sciences' training program should be broadened to include, in addition to mentoring components, formalized, ongoing programs to educate staff on a full range of issues: scientific methodology, continuity, note keeping, scientific developments, testimonial matters, independence and impartiality, report writing, the use of language, the scope and limitations upon findings, and ethics. This can only come with the appropriate allocation of funding dedicated to training.

Recommendation 26 - Proficiency testing

The Centre of Forensic Sciences should increase proficiency testing of its scientists. Efforts should be made to increase the use of blind and external proficiency testing for analysts. Proficiency testing should evaluate not only technical skills, but interpretive skills.

Recommendation 27 - Defence access to forensic work in confidence
  1. The Centre of Forensic Sciences, in consultation with other stakeholders in the administration of criminal justice, should establish a protocol to facilitate the ability of the defence to obtain forensic work in confidence.
  2. The Centre should facilitate the preparation of a registry of duly qualified, recognized, independent forensic experts. This registry should be accessible to all members of the legal profession.
Recommendation 28 - The Role of the Scientific Advisor

A ‘scientific advisor,' contemplated by the Campbell mode, serves an important role and addresses concerns identified at this Inquiry. The use of a ‘scientific advisor' should, therefore, be encouraged. There should be no prohibition upon the designation as scientific advisor of a forensic scientist who is directly involved in the forensic examinations associated with the case. This is impracticable. However, mindful of the concerns identified at this Inquiry, the CFS should encouraged, where practicable, to designate a scientific advisor who is not also the scientist whose own work is likely to be contentious at trial.

Recommendation 29 - Post-conviction retention of original evidence

The Ministries of the Attorney General and Solicitor General, in consultation with the defence bar and other stakeholders in the administration of criminal justice, should establish protocols for the post-conviction retention of original evidence in criminal cases.

Recommendation 30 - Protocols for DNA testing

The Ministries of the Attorney General and the Solicitor General, in consultation with the forensic institutions in Ontario, the defence bar and other stakeholders in the administration of criminal justice, should establish protocols for DNA testing of original evidence.

Recommendation 31 - Revisions to Crown Policy Manual respecting testing

The Ministries of the Attorney General and Solicitor General should amend the Crown Policy Manual on physical scientific evidence to reflect that forensic material should be retained for replicate testing whenever practicable. Where forensic testing at the instance of the authorities is likely to consume or destroy the original evidence and thereby not permit replicate testing, the defence should be invited, where practicable, to observe the testing. Where defence representation is impracticable (or where no defendant is as yet identified), a full and complete record must be maintained of the testing process, to allow for as complete a review as possible.

Recommendation 32 - DNA data bank

A national DNA data bank, as contemplated by Bill C-3, now before Parliament, is a commendable idea, proven in other jurisdictions, and it should be adopted in Canada.

Recommendation 33 - Backlog at the Centre of Forensic Sciences

The Centre of Forensic Sciences should eliminate its backlog through increased use of overtime and an increased complement of scientists and technicians to enable it to provide timely forensic services. This can only come with the appropriate allocation of government funding specifically earmarked for this purpose.

Recommendation 34 - Forensic research and development

The Centre of Forensic Sciences should dedicate resources to research and development. The Province of Ontario should provide adequate funding to implement this recommendation.

Recommendation 35 - Resource requirements

The specific recommendations referable to the Centre of Forensic Sciences involve, by necessary implication, the infusion of additional financial resources into the Centre. It is imperative that such an infusion occur, to ensure that the Centre can serve a pre-eminent role as a provider of critical forensic services, that it can do so in an impartial, accurate and timely manner, and that future miscarriages of justice can thereby be avoided. In this context, miscarriages of justice include both the arrest and prosecution of the innocent, and the delayed or failed apprehension of the guilty.

b) The Inquiry Regarding Thomas Sophonow

  • POLICE NOTEBOOKS
    At the present time, officers, upon retiring or leaving the force, are required to keep their notebooks. This is unsatisfactory. At the Inquiry, evidence was given by conscientious officers that notebooks, which they kept in their homes after retirement, had been lost or irreparably damaged by fire or flood. This should not happen. The Municipality should be responsible for saving officers' notebooks. They should be kept preferably for 25 years, or at least 20 years, from the date that the officer leaves the force or retires. There are changes that occur in forensic science; witnesses emerge; or new physical evidence is discovered; and any of these elements may make a reinvestigation necessary. In those circumstances, the original notes would be of great importance. I realize that storage is a problem. However, the notebooks might be preserved by way of microfiche. In any event, storage should not become an insurmountable problem for the Police Service or the Municipality. The notes must be kept on file for the requisite time.
  • EXHIBITS (whether filed in court or gathered in the course of the investigation)
    These exhibits should also be stored for at least 20 years from the date of the last appeal or the expiry of the time to undertake that appeal. These should be preserved for the same reasons set out for the preservation of police notebooks. They should only be given to someone, such as an officer who investigated the crime, if a court order to that effect is obtained. Notice of such an application should be given to the Attorney General of the Province and to the accused. Exhibits should not be given to a police officer or former officer unless a court order has been obtained.
  • MATERIAL LINKING SUSPECTS TO A CRIME
    Whenever the police seek to link material at a crime scene to a particular geographic location or a specific manufacturer which, in turn, links a suspect to a crime, that material must be tested if a test can identify a specific location or manufacturer. The duty to perform the test lies with the prosecution, whether it be the police or the Crown. The failure to perform the test on the material in question constitutes a serious omission. As a consequence of that omission, evidence as to the material's location or provenance must be ruled inadmissible.
  • RAISING PREJUDICIAL ISSUES WITHOUT ADEQUATE EVIDENCE
    Crown Counsel should always maintain high standards of fairness in their role of prosecutor. That duty requires them to consider issues carefully and to exercise great restraint before raising an issue which will be highly prejudicial to the accused in situations where there is little evidence to support it. To do so may well result in an Appellate Court very properly finding that the trial was unfair.

III. MACFARLANE PAPER

Bruce MacFarlane Q.C., following an analysis of the perils of the reliance on unreliable forensic evidence and faulty expert opinion testimony, made the following recommendations:[209]

The risk that scientific evidence may mislead a court has several dimensions. Organizationally, a forensic laboratory may be too closely linked with law enforcement and the investigative function, causing scientists to feel aligned with the police. The very nature of the proposed evidence (or its manner of presentation) may be so imprecise and speculative that whatever probative value it may have is significantly outweighed by its prejudicial effect. During the trial, defence counsel need the tools to test the accuracy and value of the evidence through an effective cross-examination. I will deal with each in turn.

a) Organizational Issues

Forensic labs should be independent from the police. Ideally, that means an independent, stand-alone organization with its own management structure and budget. If located within a policing or law enforcement organization, it should minimally be segregated into a specific branch or division, with a separate management structure and budget, physically located away from investigative units.

b) Reliability Issues

  • Microscopic hair comparison evidence should be abandoned in favour of DNA testing on any matter of significance.
  • Expert evidence which advances a novel scientific theory or technique should be subject to special scrutiny by prosecutors and the judiciary to determine whether it meets a basic threshold of reliability, and whether it is essential in the sense that the trier of fact will be unable to come to a satisfactory conclusion without the assistance of an expert.
  • Forensic experts should avoid language that is potentially misleading. Phrases such as “consistent with” and “match”, especially in a context of hair and fiber comparisons, are apt to mislead. Other examples include the assertion that an item “could have” originated from a certain person or object – when, in fact, it may or may not have.

c) Effective Cross-Examination

During pre-trial disclosure, the defence will usually receive forensic reports outlining the tests that were performed and describing, in conclusive terms, the results reached. These are often inadequate for independent review.

  • Defence counsel should be provided with the underlying raw data: the actual test results, notes, worksheets, photographs, spectrographs, and anything else that will facilitate a second, independent assessment.
  • Defence counsel should be entitled to see the written correspondence and notes of telephone conversations between the investigators and the laboratory about the examination in question.
  • Defence counsel should receive a description of any potentially exculpatory conclusions that reasonably arise from any testing procedures undertaken by the laboratory relied upon by the prosecution.

d) Preservation of Exhibits and Notebooks

Increased anxiety over the possibility of wrongful convictions heightens the need to preserve key elements of a case for later review. At a minimum, in homicide cases, the prosecution and police file, exhibits tendered at trial, and evidence gathered but not used ought to be preserved for 20 years. Recently, DNA examination of a 24-year-old bodily sample has, in one fell swoop, both exonerated a convicted person in prison for 23 years (David Milgaard), and established the culpability of another (Larry Fisher).

These recommendations can be summarized into the following categories:

  1. Forensic laboratories must be independent entities separated from control by police and prosecution;
  2. Debunked forensic tests should not be relied upon in any form;
  3. Forensic language should be standardized to avoid misleading conclusions which potentially overwhelm the trier of fact and distort the fact-finding process;
  4. A database should be established to monitor the testimony of expert witnesses;
  5. Novel scientific study or technique should be subject to special scrutiny before being admitted into evidence;
  6. All inculpatory and exculpatory findings should be disclosed to the defence, including access to the raw data, the forensic laboratories and experts, and if possible, to the samples themselves to permit independent testing; and
  7. Procedures and protocols should be established for the preservation of exhibits and notes to permit future testing for later reviews.

IV. CASE LAW

The Supreme Court of Canada dealt with the changing role of the expert witness and the impact of their opinion evidence in R. vs. Mohan.[210] In that case, the Court said the admission of expert evidence depends on the application of the following criteria:

  1. relevance;
  2. necessity in assisting the trier of fact;
  3. absence of any exclusionary rule; and
  4. a properly qualified expert.

The Court also noted that expert evidence that advances a novel scientific theory or technique should be subject to special scrutiny to determine if it meets the basic threshold of reliability and necessity. Factors that will determine admissibility include:

  1. whether it can be, and has been, tested;
  2. whether it has been published and subjected to scrutiny or otherwise reviewed by other experts;
  3. its known or potential error rate;
  4. the existence of quality and control standards; and
  5. whether there is acceptance within the relevant expert community.

The closer the evidence approaches an opinion on the ultimate issue, the stricter the application of the scrutiny.

The Court was also cognizant of the damage caused by unreliable scientific evidence:[211]

ressed up in scientific language which the jury does not easily understand and submitted through a witness of impressive antecedents, this evidence is apt to be accepted by the jury as being virtually infallible and as having more weight than it deserves.

In R. vs. J.J.,[212] the Court expanded on its cautions and pre-conditions to the admission of expert opinion evidence. The Court was cognizant of the “dramatic growth in frequency” with which expert witnesses were called to testify and the need to impose “suitable controls…and precautions” on unreliable science.[213] Furthermore, the Court re-emphasized its direction that the trial judge should assume the role of “gatekeeper” to ensure not only fairness to the parties to present “the most complete evidentiary record consistent with the rules of evidence,” but to exclude expert evidence which may distort the fact-finding process. In reiterating the criteria to be applied by the trial judge in acting as gatekeeper, the Court accepted the criteria prescribed by the United States Supreme Court[214] which would be particularly helpful in evaluating the soundness of novel or newly developed and applied scientific techniques.

In R. v. D.D.[215] the Court held that mere helpfulness, or a finding that the evidence might reasonably assist the jury, is not enough to admit an expert's opinion. Such opinion evidence is only admissible if exceptional issues require special knowledge outside the experience of the trier of fact. The Court also noted that the dangers associated with opinion evidence are not eliminated by the governing rules of admissibility.

As long as there is some admissible evidence to establish the foundation for the expert's opinion, the trial judge cannot instruct the jury to ignore the testimony. The trial judge must, however, warn the jury that the more the expert relies on facts not proved in evidence, the less weight the jury may attribute to the opinion.[216] The trier of fact can and must use good common sense in considering the value of expert evidence. It must consider the qualifications and impartiality of each expert. It must consider whether the evidence supports the assumptions upon which the opinion is based and it must consider the whole opinion itself.[217]

V. RECOMMENDATIONS AND GUIDELINES

In any given week, a prosecutor may be required to deal with a host of experts representing a diverse range of disciplines, such as: medical practitioners and pathologists, psychiatrists, psychologists, blood-alcohol analysts, traffic accident reconstruction analysts, forensic laboratory technicians, and fingerprint comparison analysts, to name a few. There is no question that over time and through experience, a prosecutor will develop a basic understanding in the areas of the regular expert witness. However, in an age of complex prosecutions, ever growing case loads and constraints on time and resources, the ability to remain current on significant developments and advances in these and other fields of expertise is limited. This is more apparent when new or novel areas of expertise arise and are to be relied upon in a specific prosecution.

Prosecutors would therefore benefit from seminars conducted by a variety of experts and incorporated in regular and ongoing education sessions. These sessions would be invaluable, as they would give prosecutors the opportunity, through direct contact and discussion, to receive more intensive training and insight into the various disciplines. These seminars could include:

  • the fundamental role of the expert;
  • explanation of the specific language or terminology used;
  • the steps undertaken to reach an opinion;
  • the certainty or qualifications on the opinion to be offered;
  • how to handle the defence expert and in particular identification of new developments or advancements that may have an effect on future opinions and prosecutions; and
  • proper techniques for the examination and cross-examination of the expert witness.

Besides the education sessions offered by individual prosecution services, prosecutors as a group would greatly benefit from the establishment of a centralized repository, which would catalog and collect all types of information and resources relative to experts. This repository, with access available to prosecutors from across the country, could include:

  • case law;
  • newsletters and articles;
  • reliability of current techniques;
  • the latest developments and advancements in specific fields of expertise;
  • sources of literature and study guides;
  • directories of professional organizations from across the country (including criteria for the qualifications of specific experts);
  • prosecution policies; and
  • teaching aids.

A Web-based model could be developed to permit online access and regular updating of the information to maintain its currency. This is cost-efficient and would maintain a transparent and objective source of information. The cost of funding this repository could be shared between the federal and provincial governments and operated by the participating organizations. Accordingly, it is recommended that the Heads of Prosecutions Committee consider the feasibility of the creation of this national centralized repository.

Prosecutors should not shy away from the use and reliance on novel scientific technique or theory in the appropriate situation, providing there is a sufficient foundation to establish the reliability and necessity of these opinions and that its probative value does exceed its potential prejudicial effects. Noting the perils from the historical misuse of expert evidence, a prosecutor should be diligent in obtaining and adducing sufficient evidence to meet the factors in support of reliability (i.e. can the theory or technique be empirically validated? Is there a professional association or society offering continuing education to its recognized members? Is there a meaningful certification program? Can the findings be reliably recreated and tested by qualified examiners?) Above all else, the prosecutor must be satisfied that this evidence will be used for a proper purpose.

The issues of reliability and necessity apply with like force to expert evidence sought to be adduced by the defence. Prosecutors should be equally diligent in assessing the proposed defence evidence and oppose its introduction if does not meet the fundamental criteria for admission or if its effect would be to distort the fact-finding process.

In the final analysis, the key issues to be considered are:

  1. The validity of the science;
  2. The qualifications of the expert;
  3. The quality and validity of the testing procedures;
  4. The objectivity and independence of the opinion;
  5. The proper evidentiary foundation being laid; and
  6. Relevance to an issue in dispute.

Prosecutors must be reminded of the existence and effect of Section 657.3 of the Criminal Code. While this section does not involve the issue of the admissibility of expert evidence, it does however create a number of statutory obligations on the party which intends to tender or call this evidence at a proceeding. Any party to the proceeding who intends to call an expert to testify must, no later than 30 days before the hearing, give notice to the opposing party of this intention, together with the name of the witness, description of the area of expertise and a statement of qualifications of the expert. The prosecutor must, within a reasonable time before the hearing, provide the accused with a copy of any report prepared by the expert, or if no report was prepared, a summary of the opinion anticipated to be given. The accused is obligated to disclose to the prosecutor any report of its expert, or in absence of a report, a summary of the opinion to be given by the expert. That obligation does not arise until after the prosecution has closed its case. If there has not been compliance with these provisions, the court may grant the opposing party an adjournment to prepare for cross-examination of the expert, order disclosure of the report or summary and permit the recalling of other witnesses to respond to matters raised by this expert, unless it is deemed inappropriate to do so.

Expert opinions and testimony represent one form of circumstantial evidence that may be presented at trial. If due care and diligence is employed in the presentation of the opinion, with attention to the establishment of the sufficiency of the factual underpinning supporting it and with the fairness of the trial process in mind, the possibility of a miscarriage of justice arising from its use is significantly reduced.

VI. SUMMARY OF RECOMMENDATIONS

  1. Prosecutors should receive training on the proper use, examination and cross-examination of expert witnesses during ongoing and regular education sessions.
  2. The Heads of Prosecutions Committee should consider the feasibility of establishing a national central repository to catalog and track, among others:
    • case law;
    • newsletters and articles;
    • reliability of current techniques,
    • the latest developments and advancements in specific fields of expertise;
    • sources of literature and study guides;
    • directories of professional organizations from across the country (including criteria for the qualifications of specific experts);
    • prosecution policies;
    • teaching aids.

    This applies to all Web-based models permitting online access to the data and regular updating of information to maintain currency.

  3. Prosecutors should not shy away from the use and reliance on novel scientific technique or theory in the appropriate situation providing there is a sufficient foundation to establish the reliability and necessity of these opinions and that the probative value does not exceed the potential prejudicial effects.
  4. Prosecutors should be reminded of the existence of Section 657.3 of the Criminal Code and the requirements and reciprocal obligations of disclosure imposed on all parties to a proceeding intending to tender expert evidence at trial.

  • [207] For example, as a result of concerns raised on the propriety of particular expert opinions, on April 23, 2003, the Deputy Attorney General of Manitoba announced the establishment of an advisory committee to examine criminal cases prosecuted in Manitoba where the Crown relied upon certain types of forensic evidence.
  • [208] See MacFarlane, at page 55. MacFarlane details the case of Fred S. Zain, a Serologist and State Trooper employed within the Serology Division of the West Virginia State Police Crime Laboratory. A judicial inquiry uncovered a massive fraud involving over one hundred and thirty four (134) of Zain’s court cases resulting in seemingly endless post-conviction habeas corpus proceedings that will extend well beyond Zain’s death in 2002.
  • [209] pp. 82-83.
  • [210] [1994] 2 S.C.R. 9.
  • [211] Ibid., at par. 19.
  • [212] [2000] 2 S.C.R. 600.
  • [213] This is the first decision of the Supreme Court of Canada to use the phrase “junk science.”
  • [214] Daubert v. Merrill Dow Pharmaceuticals, 509 U.S. 579 (1993).
  • [215] (2000), 148 C.C.C. (3d) 41 (S.C.C.).
  • [216] Lavallee vs. The Queen, (1990) 55 C.C.C. (3d) 97 (S.C.C.).
  • [217] R. vs. Muchikekwanape [2002] M.J. No. 253 (Man. C.A.).

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