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Why Should Members of the Bar Obtain Increased Continuing Education Respecting Forensic Measurement?

Why Should Students of Forensic Science Care About Forensic Measurement?

Excerpt from Report of the Motherisk Hair Analysis Independent Review page xix Glossary:

qualitative (result)

A result that provides an indication of drug presence as a positive (yes) or negative (no), rather than providing actual quantitative results.


quantitative (result)
A result that is reported containing the actual concentration of the drug in a sample, indicating a degree of precision and accuracy.

Excerpt from Report of the Motherisk Hair Analysis Independent Review pages 4 - 6:

Use for Forensic Purposes

MDTL’s hair tests were forensic in nature, and the service it offered to child protection agencies and law enforcement was a forensic one. A hair test can be forensic even if it is never tendered as evidence and even if no court proceeding is ever initiated. What distinguishes a clinical test from a forensic test is the purpose behind the test. If the test is either carried out or used for a legal purpose, it is a forensic test.

To be used in child protection or criminal proceedings, forensic tests must be carried out in accordance with forensic standards. International forensic standards are articulated in several sources:

•    international guidelines on the science of hair testing (including the consensus statements of the Society of Hair Testing), as well as on the standards of forensic toxicology laboratories generally (including, for example, the guidelines of the Society of Forensic Toxicologists and the American Academy of Forensic Sciences);

•    the standards that are required to be met for the accreditation of forensic laboratories (including the requirements under ISO 17025:2005, General requirements for the competence of testing and calibration laboratories);

•    best practices that are commonly accepted and recognized by forensic toxicology laboratories around the world; and

•    the academic literature on the science of hair testing and the interpretation of hair test results.

Although the leaders of MDTL had relevant experience as research or clinical toxicologists, none of them had any formal training or experience in forensic toxicology. Indeed, none of them considered themselves to be forensic toxicologists. Perhaps this lack of training and experience is why neither MDTL nor the Hospital for Sick Children (SickKids or the Hospital) appears to have appreciated that the Laboratory was engaged in forensic work and that it was required to meet forensic standards. The result was inevitable: MDTL’s testing and operations fell woefully short of internationally recognized forensic standards.

Adequacy and Reliability

The hair-strand drug and alcohol testing used by MDTL between 2005 and 2015 was inadequate and unreliable for use in child protection and criminal proceedings. I explain these conclusions below with reference both to MDTL’s analytical practices and to its interpretation and communications practices.

Analytical Practices: 2005–10

In the 2005–August 2010 period, MDTL’s analytical practices for drugs of abuse suffered from two fatal flaws:

1. the Laboratory relied on the unconfirmed results of its enzyme-linked immunosorbent assay (ELISA) tests[2] – a preliminary screening test – both qualitatively (to distinguish positive hair samples from negative ones) and quantitatively (to calculate the drug concentration in the sample); and

2. the Laboratory had no written standard operating procedures for the hair tests it carried out, thereby calling into question the reliability and standardization of all its testing procedures.

Although there were other deficiencies, these two alone were sufficient to render MDTL’s hair tests inadequate and unreliable during this period.

[2] A glossary of scientific terms appears at the beginning of the Report.

Excerpt from Report of the Motherisk Hair Analysis Independent Review pages 240-241:

6.    Recommendations for the Justice System

45. In Chapters 9 and 10, I consider the manner in which hair-strand drug and alcohol testing has been used in child protection and criminal proceedings.12 The use of forensic science in court proceedings poses many challenges. As a first step, the scientific evidence that is proffered must itself be accurate and reliable. I have concluded that the MDTL hair test evidence was neither.

46. Commissioner Goudge’s recommendations arising from his review of forensic pathology apply with equal force to the science of forensic toxicology as it relates to hair tests. Of particular relevance are his many recommendations aimed at reducing the risks of an expert opinion being misunderstood: for example, his emphasis on the importance of forensic training, the careful use of terminology and plain language in opinion evidence, transparency, and clear communication of those areas where there are limitations on or controversy concerning the opinion.

47. The Goudge Report provides recommendations for the courts. Those recommendations include the judicial responsibility to set the parameters of the area of expertise and to ensure threshold reliability of both the witness and the science. Following the inquiry’s recommendations, the National Judicial Institute, which is a judge-led organization, increased its science and expert evidence education for judges and made available on its website a Science Manual for Canadian Judges.[13] I too recommend ongoing and expanded judicial education regarding expert evidence, particularly expert scientific evidence.

48. I also recommend increased education for members of the bar. Counsel must be increasingly vigilant to ensure that justice is not undermined by the use of flawed forensic evidence. Counsel should ensure that they understand the scope and limitations of a forensic toxicologist’s (or any expert’s) expertise and opinions. They should exercise care to seek to qualify an expert properly and to set precise parameters on that expert’s area of expertise. Counsel must not frame questions that invite forensic experts to stray outside their expertise or the outer boundaries of the science. Lawyers should be vigilant through their questions about the use of terminology that may breed misunderstanding or misinterpretation.

49. I commend Commissioner Goudge’s extensive recommendations to all participants in the justice system. Those recommendations continue to provide crucial guidance on how the legal community must use science in the interests of justice.

[13] National Judicial Institute, Science Manual for Canadian Judges (Ottawa, 2013), online:

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