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DUI Metrology Dictionary

duidictionary.com

Instrument malfunction (defence)

Post Bill C-2 we were able to use this "defence", really a negation of the presumption, if we were able to connect that malfunction with the reliability of the measurement result. That "defence" is gone now. Malfunctioning instruments result in conclusive proof, unless we can mount a constitutional challenge. Under Bill C-2, defence lawyers and judges had a lot of trouble with the concept of "malfunction". What is it? It is not just an error message. It should relate to the "function" of an approved instrument, namely to give a reliable QUANTIFICATION of the measurand, blood alcohol concentration, at time of use. Take a close look at the analysis in St-Onge Lamoureux and attempt to understand what "reliability" means in that judgment. I think poor calibration or lack of evidence of good calibration or re-calibration will result in a malfunction. I think poor use of standard operating procedures (individual or systemic) result in malfunction or operator error. Unique body or ambient presentations can result in malfunction (see body temperature in case referred to in St-Onge).

If you are a member of the public, please don't attempt to use what you see or read at this site in Court. It is not evidence. The author is not a scientist. The author has a great deal of experience in cross-examining scientists about these issues, but the author is not a scientist. Hire a criminal lawyer in private practice in Ontario. Your lawyer can retain an expert. The author is a retired lawyer, not a lawyer in private practice. Read the statement of the purpose of this web site below.

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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.

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