• Stephen Biss

Start By Defining "Reliability" don't focus on "Accuracy"


To remind the Court, "thing 1" in 258(1)(c) is unconstitutional under Charter 11(d) (R v St-Onge) but is saved by section 1.

To remind the Court that 258(1)(c) is saved by section 1 because of Parliament's purpose which is weight consistent with scientific reliability.

To demonstrate to the Court that the SCC in St-Onge relied on the paper by Brian Hodgson. To bring that paper before the Court and make it an exhibit.

To ask the government scientist to concede the definition of "accuracy" in the Hodgson paper.

To ask the government scientist to concede the definition of "precision" in the Hodgson paper.

To ask the government scientist to concede the definition of "reliability" in the Hodgson paper, at least as it refers to instrumental reliability. The paper also contemplates other components of scientific reliability, i.e. good laboratory practice, see abstract.

To highlight the portion of the definition of "reliability" that contemplates "drift" ... "over time".

To demonstrate that such a definition requires empirical evidence of accuracy and precision at one time compared with accuracy and precision at a subsequent time.

To suggest that the ATC/CFS approach to determination of scientific reliability "at time of use" is not empirical - it is not an empirical approach and the approach is not supported by the scientific literature.

To suggest that the approach by the ATC/CFS of relying on a single data point control test, to determine reliability, renders any analysis by the instrument "qualitative" rather than "quantitative".

To connect such misuse with the principles of the Motherisk Inquiry Report.

To lay the groundwork for the argument that Criminal Code forensic use of what Parliament contemplates is a quantitative analysis instrument, in a manner that only results in a instrument qualitative analysis will result in an unlawful search under Charter section 8.

See pages 6-7 of the Motherisk Inquiry Report on confusion of qualitative and quantitative analysis as being unacceptable for a forensic purpose:

ELISA is widely used in both forensic and clinical toxicology as a screening test. It is intended to determine quickly if a sample is negative and merits no further testing or if it is a preliminary positive, in which case the sample must be tested again using another method (a confirmation test) to determine if the sample is in fact positive. e requirement to carry out a confirmation test on any preliminary positive results from immunoassay-based screens, such as ELISA, was highlighted in the literature and in all internationally recognized hair-test- ing standards well before 2005. Indeed, the Immunalysis kits that MDTL used included an explicit warning for the user about the preliminary nature of the ELISA results.

Until August 2010, MDTL reported its ELISA results to customers without a confirmation test. It reported its ELISA results – both qualitatively (as positive vs. negative) and quantitatively (in the form of a numerical drug concentration for positive samples). Such a practice is inconsistent with internationally recognized forensic standards and is unacceptable for two important reasons.

First, unlike confirmation techniques such as gas chromatography–mass spectrometry (GC-MS) or liquid chromatography–tandem mass spectrometry (LC-MS/MS), ELISA cannot identify the substances within a sample. Second, MDTL’s practice of using ELISA to quantify drug concentrations is simply unheard of in forensic toxicology lab- oratories. No forensic toxicology laboratory in the world uses ELISA testing the way MDTL did.

See pages 52-53 of the Motherisk Inquiry Report on number of calibrators required for quantitative v. qualitative analysis:

#accuracy #precision #reliability #Hodgson #drift #overtime #Motherisk #quantitativeanalysis

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