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    Maybe the Instrument Is No Longer Linear Enough to Be An "8000C"
    Stephen Biss
    • May 22, 2018
    • 5 min

    Maybe the Instrument Is No Longer Linear Enough to Be An "8000C"

    Purpose: To explore the analytical variability of the 8000C as determined by the Alcohol Test Committee during evaluation of the 8000C prior to type approval. To compare the analytical variability of the individual 8000C used in the subject tests for the client with the analytical variability of the type or class 8000C determined by the Alcohol Test Committee. To suggest that the instrument in the matter before the Court may no longer be a member of that class or type because
    19 views0 comments
    BAC Analysis in a Lab Without Bracketing Controls is at Best Qualitative not Quantitative
    Stephen Biss
    • Apr 27, 2018
    • 4 min

    BAC Analysis in a Lab Without Bracketing Controls is at Best Qualitative not Quantitative

    We have a serious problems in the Canadian criminal justice system. One of them is the failure of Parliament and the Courts to recognize the differences between a qualitative measurement (a screening device result like a rapid home use COVID test kit or a roadside breath ASD, PBT, or ADSE tester result) and a quantitative measurement that results in criminal law sanctions. The Criminal Code and our case law, to some extent recognize the differences between an approved instrum
    8 views0 comments
    Change at One Point but Not at Another Point that is Equivalent
    Stephen Biss
    • Apr 13, 2018
    • 5 min

    Change at One Point but Not at Another Point that is Equivalent

    This is a sample excerpt from a cross-examination of a Crown expert using data from periodic inspection of an approved instrument. The multiple-point control test data from an annual periodic inspection in Ontario or from a re-calibration as in Vallentgoed can be very useful to the defence in cross-examing a breath tech or a Crown expert to identify drift in accuracy and precision over time. Purpose: To suggest that there is empirical evidence in the matter before the Court o
    1 view0 comments
    Police Fail to Correct a Linearity Problem on In-House Annual Inspection
    Stephen Biss
    • Mar 29, 2018
    • 6 min

    Police Fail to Correct a Linearity Problem on In-House Annual Inspection

    Let's suppose that you obtain disclosure or Freedom of Information documents respecting In-house Periodic Inspections by your local police service of their approved instruments. What can you do with that information? Purpose of this example cross-examination: To obtain an admission from the CFS scientist that the disclosed annual maintenance records indicate that the police failed to take any steps to correct control tests on inspection that indicated the instrument's respons
    9 views0 comments
    Why Does the ATC Say Single Point Control Tests are Good Enough?
    Stephen Biss
    • Mar 25, 2018
    • 6 min

    Why Does the ATC Say Single Point Control Tests are Good Enough?

    Purpose: To explore the differences between a measurement instrument that has a linear relationship between the thing measured and the result v. a measuring instrument that has a calibration curve. To search for an admission that the calibration curve can shift up or down, left or right, or rotate around a point over time. To cross-examine the CFS expert on the lack of empirical study supporting the ATC/CFS hypothesis that a single point control test can always detect drift.
    8 views0 comments
    Response Drifts Over Time
    Stephen Biss
    • Mar 23, 2018
    • 3 min

    Response Drifts Over Time

    In an article relied upon by the SCC in St. Onge, Brian Hodgson stated: Defence lawyers need to educate themselves about the meanings of "drift" and "over time". What is it that actually "drifts"? What happens "over time". Are these concepts important to clarify during any cross-examination of a Crown expert? Can the reality of drift over time be satisfied by single point control tests? Is more required to maintain reliability over time? The ATC and CFS regularly opine that a
    4 views0 comments
    What is measurement?
    Stephen Biss
    • Feb 15, 2018
    • 6 min

    What is measurement?

    Purpose: Cross-examination of a CFS scientist on the VIM. To connect "measurement" in Canadian evidentiary breath testing to "measurement" in the international literature, specifically the International Vocabulary of Metrology (the VIM Exhibit 18), referred to in most international scientific literature on measurement To define any measurement in Canada, including a measurement for a forensic purpose as a comparison. To obtain admissions from the CFS scientist as to the appli
    2 views0 comments
    Stephen Biss
    • Jan 13, 2018
    • 1 min

    Control Tests do not displace Formal Calibration Intervals

    Purpose: To separate conceptually control tests from calibration To obtain an admission that there are no "assessors" in the province of Ontario To obtain an admission that the historical maintenance records show a deterioration of performance - deterioration of linearity in this particular instrument The strategy of using control tests as indication of reliability depends upon completeness of records and transparency To obtain an admission that at the bottom of the valley in
    0 views0 comments
    Linearity Studies are Done on New Instruments not Aging Instruments
    Stephen Biss
    • Jan 12, 2018
    • 2 min

    Linearity Studies are Done on New Instruments not Aging Instruments

    Purpose: To obtain admissions that the published studies dealing with the linearity of approved instruments assume a new instrument recently calibrated by the manufacturer. Sample cross-examination of CFS expert on the inadequacy of studies relied upon by government scientists to maintain that approved instruments have good linearity - the studies were all done on new instruments, recently calibrated at the factory, not on aging instruments out in the field: Q. Well, every s
    2 views0 comments
    Instrumental Deviations from Beer-Lambert Law
    Stephen Biss
    • Jan 11, 2018
    • 10 min

    Instrumental Deviations from Beer-Lambert Law

    This blog entry explores the use of a university textbook during cross-examination of a CFS scientist on "Instrumental Deviations from Beer-Lambert Law". The purposes of this cross-examination included: To explore the reasons why measurement instruments in the field may deviate from the linearity alleged by the Beer-Lambert law. To introduce a university textbook dealing with inter alia: External Calibration Creating a Calibration Curve Limits to Beer's law No longer linear w
    24 views0 comments
    Beer-Lambert Law as Stated in Training Aid is Over-Simplified and Inadequate
    Stephen Biss
    • Jan 10, 2018
    • 10 min

    Beer-Lambert Law as Stated in Training Aid is Over-Simplified and Inadequate

    This blog entry contains excerpts from the cross-examination of a CFS scientist during an over 80 trial. It was suggested to the scientist that light in the Intoxilyzer sample chamber is polychromatic, rather than monochromatic. The Beer-Lambert Law as described in the CFS Training Aid assumes that the infrared light in the sample chamber is monochromatic, i.e. that there is one constant co-efficient for ethyl alcohol. Because the infrared infrared light in the sample chambe
    7 views0 comments

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    For more information respecting this database or to report misuse contact: Allbiss Lawdata Ltd., Mississauga, Ontario, Canada, 905-273-3322. The author and the participants make no representation or warranty  whatsoever as to the authenticity and reliability of the information contained herein.  WARNING: All information contained herein is provided  for the purpose of discussion and peer review only and should not be construed as formal legal advice. The authors disclaim any and all liability resulting from reliance upon such information. You are strongly encouraged to seek professional legal advice before relying upon any of the information contained herein. Legal advice should be sought directly from a properly retained lawyer or attorney. 

    WARNING: Please do not attempt to use any text, image, or video that you see on this site in Court. These comments, images, and videos are NOT EVIDENCE. The Courts will need to hear evidence from a properly qualified expert. The author is not a scientist. The author is not an expert. These pages exist to promote discussion among defence lawyers.

    Intoxilyzer®  is a registered trademark of CMI, Inc. The Intoxilyzer® 5000C is an "approved instrument" in Canada.

    Breathalyzer® is a registered trademark of Draeger Safety, Inc., Breathalyzer Division. The owner of the trademark is Robert F. Borkenstein and Draeger Safety, Inc. has leased the exclusive rights of use from him. The Breathalyzer® 900 and Breathalyzer® 900A were "approved instruments" in Canada.

    Alcotest® is a registered trademark of Draeger Safety, Inc. The Alcotest® 7410 GLC and 6810 are each an "approved screening device" in Canada.

    Datamaster®  is a registered trademark of National Patent Analytical Systems, Inc.  The BAC Datamaster® C  is an "approved instrument" in Canada.