DEFENDING AGAINST A QUANTITATIVE ANALYSIS FOR A FORENSIC PURPOSE
Issues in Cross-examining Government Scientists About Measurement Science
Help for Canadian Criminal Defence Lawyers Defending DUI Charges
Image below of "reliability" definition is from Hodgson, Brian T., "The Validity of Evidential Breath testing", Can. Soc. Forensic Sci. J. Vol. 41 No 2 (2008) pp. 83-96. See also R. v. St‑Onge Lamoureux,  3 SCR 187, 2012 SCC 57 (CanLII):
Contact us at 905-273-3322 if you are a Canadian criminal defence lawyer and you need help developing a defence to a DUI charge under Bill C-46.
A good starting point is to think about issues that can be raised during cross-examination of Crown witnesses. Over 40 years, we have learned how to build good defences and win DUI trials. Now we help our colleagues, throughout Canada, find "evidence to the contrary" that is permitted under Bill C-46, and use expert evidence to displace "conclusive proof".
If you are a Canadian criminal defence lawyer, we can help you to defend a DUI in Canada through:
3. Hands-on training with evidentiary breath testing equipment
5. Private Consultation
The following are proper and relevant issues to be raised, and purposes for, cross-examinations on the scientific reliability of measurement instruments used for forensic purposes, including breath instruments and drug testing instruments:
To obtain admissions that the 2012 Alcohol Test Committee Position Paper:
- is a position paper
-is not a scientific article
-is not a research paper
-does not have any external references in international literature
-does not have any references outside of the CSFS Journal
-has no references to international metrology
-has positions not supported by empirical research
-is not scientific opinion, it is position
To obtain admissions that the opinion of the Crown expert (and indirectly the 2012 ATC Position Paper) that single point control test(s) at time of use are adequate to establish reliability is based upon a hypothesis that has no empirical study to support the hypothesis.
To challenge the assumption by the Crown expert (and indirectly the 2012 ATC Position Paper) of continued linearity of response in aging instruments.
To challenge the Crown to produce any empirical study that supports the Crown expert's (and the ATC's) hypotheses.
To ultimately suggest that the 2012 ATC Position Paper is not based on science, but rather policy.
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 it is no longer capable of maintaining the analytical variability of the type or class.
To suggest that the instrument in the matter before the Court may no longer have the linearity of the class or type 8000C because it no longer exhibits the linearity established during evaluation of the type or class.
To establish that we have some evidence, that the linear kind of relationship, the created linear relationship that’s done by means of the calibration curve in terms of the – how the instrument works, in the case before the Court, we’ve got a possible interpretation that the relationship that normally should appear linear, the way that Ms. Martin found...is not linear.
To explain to the Court that creation of the calibration curve during factory calibration or re-calibration of an 8000C instrument takes something which is inherently non-linear and turns the instrument into a measuring device that can be used as if it were linear.
To suggest that if the instrument has lost that capability, over time, through drift, then the instrument ceases to be reliable and ceases to be a member of the type or class 8000C.
To confirm that when new instruments are being evaluated, various solutions are used between 50 and 400 mg/100mls.
To confirm that when new instruments are being evaluated, the specified accuracy requirement is +/- 5 percent of the BAC with a precision requirement of +/- 3 mg/100mls under 100 mg/100mls and +/- 2.5 percent for readings greater than 100.
To confirm that the purpose of such evaluation is to ensure the accuracy and reliability of breath tests. This process is "type approval" in the international literature.
To obtain an admission that the manufacturer advertises that its instrument is accurate plus or minus 3 milligrams per 100 mls and standard deviation doesn’t exceed 3 milligrams per 100 mls.
To obtain an admission that under the ATC Best Practices document, new instruments must be individually inspected before being placed into service to ensure that they initially meet the manufacturer's specifications.
This process is "initial verification" in the international literature.
To obtain an admission that under the ATC Best Practices document, instruments in service must be individually inspected, periodically, to ensure that they continue to meet the manufacturer's specifications.
This process is "subsequent verification" in the international literature.
To obtain admissions as to the manufacturer's specifications for accuracy and precision in its advertising, in the information given to the evaluator during type approval, and in the servicing/maintenance documents given to the people who do work on these instruments on a regular basis.
To obtain an admission that although the local police service appears to be doing annual and periodic inspections, they are doing so without reference to the manufacturer's specifications for accuracy and precision across the measuring interval of the instrument.
To obtain an admission that when government scientists conduct quantitative analysis to determine blood alcohol concentration using blood, urine, or serum, they use positive and negative controls.
To obtain an admission from the government scientist that when they conduct such quantitative analysis they use a low control, an expected midpoint control, and a high control.
To obtain an admission from the government scientist that they would never use just one control at 100 mg/100mls.
To obtain an admission from the government scientist that using just one midpoint control would be unacceptable laboratory practice.
To suggest that use of only one mid-point control in a laboratory does not assist in checking linearity.
To suggest that use of only one mid-point control in a laboratory to obtain a quantitative analysis in a laboratory would not be in compliance with ASCLD/LAB accreditation.
To obtain an admission that if the bracketing controls failed then the result is at best qualitative rather than quantitative.
To establish that if there is an indication in the maintenance records that the instrument was taken out of service for consistently low checks, it is necessary to obtain disclosure or production of the contemporaneous documentation by the inspector, who made that decision, and the printouts obtained by the inspector from the Intoxilyzer to understand the context and significance of that decision to take the instrument out of service.
To suggest that there is empirical evidence in the matter before the Court of change in response by the approved instrument at the lower end of the measuring interval (reading much lower) and at the upper end of the measuring interval (reading slightly higher) without corresponding change in response at the single data point control test level.
To suggest that linearity has therefore changed, and in other words, the calibration curve programmed into the instrument, at the factory or on the last re-calibration, is no longer reliable.
To lay the foundation for the O'Connor order.
To connect the lack of multi-point calibration of an approved breath instrument with the lack of adequate multi-point calibration of the Elisa screening system (lack of multiple (5) calibrators) - the confusion of quantitative and qualitative analysis - criticized in the Motherisk Inquiry report.
To challenge the evidence of the government expert as to the adequacy of single point control tests to establish linearity in an instrument, that has not recently been re-calibrated across the measuring interval.
To suggest that the empirical evidence in the facts of this case - the annual inspections - supports the inference that the calibration curve has shifted, rotated, or stretched (or more correctly that although the learned calibration curve was fixed at time of last calibration, it is now different -shifted, rotated, or stretched, over time - from what the correct calibration curve would be if the instrument was properly re-calibrated) i.e. accuracy and precision have drifted over time.
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.
To explain to the Court, the differences between ABA (Esc Esc B) and ACA (Esc Esc C) sequences.
To confirm that ABA sequences are not recorded in COBRA data but ACA sequences are recorded in COBRA data.
To explain to the Court why the calibration checks at 40 or 50, 100, and 300 during annual inspections do not appear in COBRA data disclosed.
To obtain an admission from the government scientist that a review of the documents from 3 annual inspections reveals a trend such that indications in the lower portion of the measuring interval are reading low and indications in the upper portion of the measuring interval are reading high, in other words, the response of the instrument to known levels of alcohol standard has drifted such that there has been a trend in change in the accuracy of the instrument.
To consider the alternative explanation that the inspectors are not following the same standard operating procedures during inspection from one annual inspection to the next.
To obtain an admission that further disclosure or production of information from the inspector on the annual inspections is necessary to properly assess these anomalies.
To obtain an admission that the inspection procedure and use of the instrument continued even though the results were outside the low end of the range / tolerance.
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 response had shifted well beyond not only a 3 mg% tolerance, but well beyond a 10mg% tolerance.
To suggest to the CFS scientist that the calibration curve has shifted.
To suggest to the CFS scientist that the instrument's response is no longer as accurate and precise as it should be per manufacturer's specifications.
To suggest that police are not following their very generous 10 mg% tolerance SOPs.
To obtain an admission that measurement results on the instrument are no longer reliable.
To obtain an admission that the police did not stop use of the instrument and report the non-conformance to a superior.
To demonstrate that when the particular instrument was first placed into service, the tolerance verified by the independent authorized service centre for each of three test values was +/- 3 mg/100mls.
To demonstrate that the initial verification matched the manufacturer's published specifications of accuracy +/- 3 mg/100mls.
To demonstrate that when the particular instrument is subsequently being annually checked, by the police service rather than the independent service centre, at each of the three test values, the checklist indicates that the acceptable tolerance is now +/- 10 mg/100mls.
To demonstrate that the instrument's calibration is no longer being verified in accordance with the manufacturer's specifications.
To demonstrate that the police service is not adhering to the best practices document of the ATC.
To establish that "traceability" is a scientific concept used in Canada.
To define "traceabilty" in a Canadian context.
To establish that "calibration interval" is a scientific concept used in Canada.
To explain the two English meanings of "standard" by reference to the difference in French between "etalon" and "norme" in the NRC document in English and French.
To introduce the concept of "calibration interval" in the international literature.
To explain the function of internal standards, the ITP, internal test procedure to the Court.
To obtain an admission that the ITP system needs annual or periodic maintenance, just like the optical bench, so that the instrument can continue to function in accordance with manufacturer's specifications.
To obtain an admission that any adjustment or re-calibration of the optical bench also requires re-calibration of the internal standards.
To establish that the hypothesis by the ATC/CFS, that any drift in instrument response (what Hodgson describes as significant drift in accuracy and precision over time) will always be caught by a single point control test, is not supported by any empirical study.
To establish that there is no study abstracted in Wigmore on Alcohol that establishes the ATC/CFS hypothesis empirically.
To confirm that the new calibration curve created after a re-calibration compared with the old calibration curve prior to recalibration can move up, move down, move sideways, or rotate in either direction around an axis that may or may not be at 100 mg/100mls.
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.
To obtain admissions about the differences between new instruments and aging instruments.
To lay the groundwork for the argument that traceability of the measurement results to the SI units is through the calibration of the individual instrument to reference standards - the étalons.
If reliability, requires traceability, then the Certificate of Calibration and the identity of the reference standards used during that calibration are relevant to the reliability of the measurement result.
To educate the Court about the calibration sequence run on the approved instrument at the factory.
To obtain an admission from the Crown expert that without the proper auto-calibration creation of a unique calibration curve, the instrument is not reliable.
To educate the Court about the Analytical Theory of the 8000C Optical Bench including Emitter, Sample Chamber, Dual Detectors, Inverse Logarithmic relationship, and building the Calibration Curve based on the theory that differing ethanol concentrations have differing % absorption of IR light.
To lay the groundwork for the importance of calibration and re-calibration respecting the reliability of any approved instrument.
To explain the auto-calibration function of the instrument that is run at the factory or the Authorized service Centre.
To lay the groundwork for why changes to the relationship between electrical signals coming off the detector and true indication result in drift in accuracy and precision, i.e. loss of reliability.
To obtain an admission that calibration or re-calibration needs to be done by an entity that is accredited by ASCLD/LAB ANLAB to ISO 17025 standards.
To obtain an admission that the local police service or local service centre which has conducted a re-calibration does not have such accreditation. The cross-examiner should have gone further on this issue to expand this line of questioning to Mega-Tech, Davtech, and GCS Technical Services.
To educate the Court as to the "why" of the unreliability of an approved instrument to measure across the measuring interval if it has not been recently calibrated, inspected, maintained, re-calibrated.
It seems strange to think that a modern "approved instrument" has to "learn" - that it has a kind of artificial intelligence. In reality it's true, an approved instrument has to learn the meanings of 67 mg/100mls, 94 mg/100mls, 117 mg/100mls, and 184 mg/100mls. The artificial intelligence uses extrapolation from its response during calibration to known values (from a NIST reference - un étalon with an unbroken chain of connection to SI units of the CGPM/BIPM in Paris) (maybe 0, 50, 100, 200, 300 or 0, 40, 80, 100, 300) that it is shown. This "calibration" is done by the calibrating or re-calibrating technician at the factory or Canadian Authorized Service Centre. A Certificate of Calibration is then prepared. This learning should never take place in the hands of the police. It should be done by a neutral entity that knows what it is doing and follows Standard Operating Procedures.
To connect evidentiary breath testing in Canada, the Criminal Code, and the Weights and Measures Act section 4(1) to the Metre Convention and the organizations created by the Metre Convention specifically the CGPM and the BIPM.
To establish the primacy of the CGPM/BIPM and its SI units and vocabulary in any consideration of measurement science in Canada and internationally.
To establish that Canada is a member state of the Metre Convention.
To lay the groundwork for an argument that there is a Principle of Fundamental Justice protection under Charter section 7 related to fair measurement in accordance with the international system of units, the SI units.
To the lay the groundwork for the principle that every measurement result must be traceable to the SI units.
To connect the concept of measurement standard, reference standard, étalon to Canadian law, Canadian constitutional law, and international measurement science.
To suggest to the Court that if measurement is a comparison, then it must always be a comparison to the international measurement standard, reference standard, étalon.
To develop the concept that, in metrology, accuracy is not a number. It is something that we work towards. It does not make sense to say that a particular measurement result "is accurate". We can take certain steps to encourage accuracy such as using the mean or average of many results. The proper approach is provide a measurement result that is as accurate as possible together with a statement of the uncertainty of the measurement.
To ultimately suggest that searches of breath are unreasonable and violate section 8 of the Charter, if police are using, for forensic purposes, "approved instruments" that are not capable of rendering reliable "quantitative analyses".
To apply the findings and conclusions of the Motherisk inquiry Report in Ontario to evidentiary breath testing in Canada.
To establish why it is essential that approved instruments, in fact, be capable of conducting "quantitative analyses" as defined in the Motherisk Inquiry Report.
To connect the Criminal Code and its wording about concentration of alcohol in units of blood with the International system of SI units.
To establish the importance of SI units and their definitions according to the CGPM when construing and applying the Criminal Code of Canada, with respect to offences defined in terms of a concentration of alcohol in units of blood.
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 applicability of the definitions in the VIM to the matter before the Court and the Criminal Code respecting:
measurement (as a comparison)
metre & kilogram
To obtain an admission from the CFS scientist that the traceability of a measurement result on an approved instrument or a truck weigh scale is through the calibration of the instrument at the factory or a proper recent re-calibration by the manufacturer or factory authorized service centre. At the time of calibration a calibration curve is created to establish a relationship between the electrical signal coming off the detector in the AI or the weigh scale and the digital indication. That isn't done using controls at time of use.
To clarify that calibration of a gas chromatogaphy instrument used for blood, urine, serum analysis is done quite differently at time of use. A calibration curve on a gas chromatograph is created electronically at time of use.
Traceability of a measurement result on an AI is therefore through the manufacturer's Certificate of Calibration or re-calibration certificate. The Certificate, reference standards, and methodology at the time of calibration or re-calibration are therefore relevant (and essential) to reliability of the measurement result.
To obtain admissions from a CFS scientist respecting the factors that influence reliability in a laboratory
To suggest that there are multiple components to "reliability"
To lay the groundwork for an argument that reliability means a lot more than a formula of two tests 15 minutes apart with 02 agreement and control tests between 90 and 110
To define scientific "reliability" using ISO 17025
To educate the Court about good laboratory practice.
To obtain an admission from the CFS scientist, that good laboratory practice requires contemporaneous documentation.
To obtain an admission from the CFS scientist that good laboratory practice requires that a technician stop, document, and report whenever an anomaly occurs.
To apply good laboratory practice to breath testing for a forensic purpose.
To further challenge the Crown's suggestion that the anomalous low cal. checks that occurred in this breath truck were not caused by a door opening from time to time in winter.
To support the O'Connor application for production of contemporaneous documentation by the QT who obtained the group of low cal. checks. Documentation would shed light on possible causes of the low cal checks, any troubleshooting attempted, and the likelihood that their cause was a problem with Intoxilyzer precision.
To use the cross-examination of the CFS scientist to educate the Court about Henry's Law.
To cross-examine a CFS scientist on use of Guth 2100 wet-bath simulator under Canadian cold operating conditions.
To build a case for O'Connor production of contemporaneous documentation by the QTs who obtained the groups of low cal. checks in the breath truck in winter.
During Direct Examination, the CFS expert had suggested in response to the Crown's request for the simplest explanation for anomalous low cal. checks, that the door being left open on the breath truck in winter could cause repeated cal. checks below 90. The purpose of this cross-examination was to suggest that if this was the case, then QTs of this police service are not using the simulator in accordance with manufacturer's recommendations for minimum ambient operating temperatures.
To obtain an admission from a CFS scientist that expectation of ATC Best Practices Recommendation is for annual inspection of wet-bath simulator to ensure it meets manufacturer's specifications.
To obtain an admission from a CFS scientist that manufacturer's specification for a Guth 2100 simulator is 34.00 +/- .05 degrees C, not just 34.0 +/- .2 degrees C.
To obtain an admission from a CFS scientist that uncertainty of measurement is not novel science.
To simplify the concept of Type A Uncertainty of Measurement to make it more understandable to a trial judge.
To obtain an admission from the CFS scientist that Uncertainty of Measurement is not novel science.
To explain calculation of average, precision, and standard deviation in simple math terminology.
To connect CFS documents that talk about coverage factor with the international literature of Uncertainty of Measurement.
To obtain admissions as to the differences in inspections, in inspection standard operating procedures, and completeness of an independent inspection v. an in-house annual or in-house periodic inspection by the local police service.
To establish that these inspections are inadequate unless accompanied by complete documentation - that needs to be produced on the O'Connor application.
To challenge the CFS expert's position that inconvenient data should be excluded for the purpose of calculating precision.
To obtain an admission that the local police service is not properly assessing accuracy and precision during periodic inspections because they are not assessing under stable conditions.
To illustrate the importance of an O'Connor order requiring production of officer's contemporaneous documentation at the time of the inconvenient data to determine the cause of the data that the CFS expert seeks to exclude, rather than speculating that the data is caused by something other than drift in accuracy and precision.
To consider the possibility that the recorded simulator temperatures (all exactly 3400) might be wrong and that there is a serious problem with documentation of simulator temperature.
To obtain an acknowledgement from a CFS scientist that even though he would exclude data outside (Maximum Permissible Error) 90 to 110 in calculating precision, at least one police service in Ontario is using data outside 90 to 110 in calculations of precision during periodic inspection.
To challenge the opinion that data outside maximum permissible error (outside +/- 10 mg%) should be excluded from any calculation of precision. The cross-examiner should have called evidence in reply from a statistician or other expert in outliers.
To establish a better methodology for calculating precision of an approved instrument in service.
To apply CFS methodology using control checks re calculation of uncertainty of measurement in blood/urine analysis to evidentiary breath testing.
To educate the Court as to the inadequacy of calculation of the instrument's precision by the local police service, close in time to the subject tests.
To obtain admissions from the CFS expert as to proper methods for calculating precision.
To confirm defence expert evidence that the local police had stopped doing linearity checks by the time of this periodic inspection.
To obtain admissions about the use of historical control test data by the Centre of Forensic Sciences in Toronto to calculate standard deviation and uncertainty of measurement.
To obtain an admission that the same approach could be used with historical data of Intoxilyzer control tests to prepare statistical data of accuracy and precision at different points in time so as to assess drift in accuracy and precision over time, in other words, reliability.
Confirming why disclosure of COBRA or other downloaded data is relevant to understanding the reasons why an instrument needed to be sent to the factory for re-calibration.
To establish the need for an O'Connor order to produce documentation of what was meant by "Consistently low cal checks in the maintenance log.
To establish the need for an O'Connor order to produce the technicians' contemporaneous documentation that went with the periodic inspections of 3 separate dates.
To establish non-compliance with the Standard Operating Procedure respecting entering accurate data into the tombstone data prior to a configuration of the alcohol standard or a subject test.
To establish improper use of the Esc Esc E function checking date and time.
To establish bad practice in recording or amending location data in the instrument.
To establish the unreliability of some of the information on the Intoxilyzer Test Record notwithstanding Criminal Code section 258(1)(f.1).
To explore the lack of a lab setting when accuracy and precision of the instrument are checked on periodic or annual inspection.
To explore the lack of Standard Operating Procedures when accuracy and precision of the instrument are checked on periodic or annual inspection.
To challenge the Crown's assertion that the AI will automatically shut down if anything is out of tolerance or ATC or manufacturer's specifications.
To remind the Court of the concept of "reliability" used by the SCC in St-Onge.
To educate the Court as to the definitions of "accuracy", "precision", and "reliability" used by Brian Hodgson in his paper relied on by the SCC in St-Onge.
To focus on drift in accuracy and precision over time from:
the manufacturer's specifications,
and/or the accuracy and precision of the 8000 that was evaluated,
and/or this specific instrument when first placed into service,
as compared with accuracy and precision close to time of use.
To support argument that the Maintenance History shows that the instrument was taken "out of service", for "consistently low cal. checks" and as a result "requires calibration". Can the matter not be distinguished from Vallentgoed where the maintenance log revealed that the instrument was taken out of service for routine maintenance and periodic re-calibration?
To support argument that the Maintenance History reveals that the instrument was taken out of service for a specific problem. Can the matter not be distinguished from Jackson para 135 (see green, orange, and blue highlighting below)?
To suggest that there is a problem with the CFS / ATC approach to assessing accuracy and precision if this instrument needed to be taken out of service - the instrument passed the CFS / ATC criteria and yet was taken out of service for some mysterious reason.
To suggest that full documentation of the mysterious reason should be the subject matter of an O'Connor order.
To distinguish R. v. Jackson on the basis of a difference in facts. The instrument in Jackson was new. See Jackson paragraph 135 highlight in red. The instrument in the matter before the Court was about 6 years old.
To suggest that ATC/CFS scientists cannot provide any scientific opinion of the reliability of aging instruments out in the field without conducting an empirical study of instruments sampled from the field.
To suggest that ATC/CFS scientists have no idea whether or not instruments in the field are performing in accordance with manufacturer's specifications.
To identify the lack of any system of "verification" in Canada that instruments in the field are performing in a manner similar to the instruments originally evaluated and given type approval.
To contrast the evaluated accuracy and precision of instruments evaluated by the ATC with actual accuracy and precision of instruments in the field.
To suggest that unlike gas pumps and retail meat scales, in Canada, we have no system in place to control "verification" that an individual instrument conforms to "type approval" of an approved instrument.
To suggest that in Canada we have no system of mandatory periodic verification of individual instruments in the field to ensure that they conform to type approval.
To obtain admissions respecting the inadequacy of ATC / CFS recommendations in requiring "stability of metrological characteristics" over time.
To obtain admissions that the Diagnostics test function only checks stability over a few seconds at best, not over weeks, months, or years following calibration by the manufacturer.
To underline the concept of "over time" in Hodgson's definition of "reliability".
To challenge the ATC hypothesis or policy that "each test stands on its own".
To identify the hypothesis as faith or policy, not scientific opinion.
To demand the wording of the hypothesis and the empirical testing methodology if it is a scientific opinion.
To identify exactly what other anchoring information ATC/CFS considers essential to reliability notwithstanding this sweeping statement.
To identify exactly what other information they label irrelevant.
To obtain an admission that this is not scientific opinion.
To educate the Court as to the difference between scientific opinion and technical opinion.
To separate the difference between a priori logical opinion and an opinion based on empirical science.
To identify the lack of empirical studies using "sampling" of aging instruments in the field.
To establish that the ATC Position Paper is not a consensus document generally accepted by all forensic toxicologists.
To introduce the concepts of "metrological control" and "metrological supervision" to the Court.
To establish that the international literature indicates that all of the approved instrument's software is legally relevant to reliability of the measuring system.
To distinguish "audit trail" (e.g. COBRA data) from instrument software (e.g. source code)
To identify that the international standard for MPE for instruments in service, 6 mg% at target 100 is much tighter than 10 mg%.
To identify that the international standard for MPE for instruments after repair is tighter than instruments in service.
To raise the concept of MPE after repair and in service at various target values across the measuring interval.
To show that the ATC recommendations for operational procedures at time of use do not account for the need during inspections to regularly conduct control tests at target values other than 100 mg/100mls.
To demonstrate that we have no metrological supervision to ensure that linearity is checked, that manufacturer's specifications are honoured across the measuring interval.
To demonstrate that searches of breath using"approved instruments" are unreasonable in Canada if there is no system in place to supervise and audit police maintenance of their instruments.
To suggest that an AI is a quantitative analysis instrument and an ASD is a qualitative analysis instrument and suggest that the Crown/CFS are confusing this distinction as happened at the Motherisk Lab.
To suggest that such confusion, if it persists, will lead to unconstitutionality of various Criminal Code sections or section 7 and 8 Charter violations.
To neutralize the CFS scientist's assertion that anomalous data should be excluded from calculation of precision.
To establish that the ASTC/CFS is not sampling from aging instruments out in the field tpo determine error rates.
To establish that the ATC/CFS is not allowing for drift in precision of instruments as they age without re-calibration.
To suggest possible acceptable or normal error rates.
To obtain an admission that the ATC Position Paper of 2012 contradicts the federal government policy in the Fairness at the Pumps Act.
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 the infrared spectrum at approximately 9.4 microns, your detection limit will certainly be degraded and precision will also suffer in most instances, if you are no longer taking the reading at the absorbant’s maximum.
To obtain an admission as to what may happen if the detector becomes dirty.
To obtain admissions from the Crown expert to enable argument that Vallentgoed can be distinguished on its facts - particularly respecting:
- recent re-calibration on a regular calibration interval
- calibration by a service provider independent of the police.
To introduce the concept of "calibration interval".
To obtain admissions as to the importance of calibration interval in the international scientific literature.
To obtain an admission that neither the ATC/CFS nor the manufacturer mandate a calibration interval for approved instruments, though the manufacturer so specifies for ASDs.
To introduce some international standards on reliability including ISO 17025.
To introduce the concept of "uncertainty growth".
To connect "reliability", "calibration interval", and "uncertainty growth" "over time".
To obtain admissions that the published studies dealing with the linearity of approved instruments assume a new instrument recently calibrated by the manufacturer.
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:
Creating a Calibration Curve
Limits to Beer's law
No longer linear when the molar absorptivities differ
Instrumental Deviations from Beer-Lambert law
Polychromatic Radiation rather than Monochromatic IR
To suggest that aging filters at the end of the sample chamber result in changes in bandwidth and more polychromatic light so less linearity.
To expose over-simplification by Crown experts.
To obtain admissions that the concept of single point control test(s) at time of use, is adequate to verify that calibration has not changed over time, is not good measurement science.
To obtain admissions that checks of linearity during annual maintenance or other periodic inspection are necessary to confirm linearity, to confirm that the instrument is still calibrated across the whole measuring interval.
To obtain an admission that although the Beer-Lambert Law suggests that the relationship between concentration in the sample chamber and the measurement result is linear (after adjusting for the logarithmic relationship of absorption/transmittance) is linear, there are instrumental deviations in the Beer-Lambert Law.
To separate the concepts of "calibration" from "control checks".
To clarify that "calibration" is something that happens at the factory, not at time of use by a qualified technician.
To clarify that control tests at time of testing are simply a verification (to use the CFS scientist's words) that calibration hasn't changed over time (note Hodgson concept of "over time" in his paper referred to in St-Onge).
To educate the Court about the meaning of "traceability" in measurement science.
To obtain an admission that there is a relationship between the calibration certificate (Certificate of Calibration) from the factory and the reference standards used during the factory calibration.
To obtain an admission that there is a relationship between the calibration certificate from the factory and the scientific reliability of the measurement result at time of use.
To introduce the NIST Certificate for the reference standards used at the time of calibration at the factory.
If you are a defence lawyer or attorney and you need help in drafting a cross-examination using some of these issues and purposes, please contact us at 905-273-3322. Online Courses and Continuing Education Programmes are also available.
Please find below, a simple explanation of the creation of the Intoxilyzer 8000C calibration curve at the factory or during re-calibration by the Canadian Authorized Service Centre. This video is an excerpt from one of our online courses for defence lawyers.