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Downloaded Data is a Key Source of Information to Find Out Reason for Re-calibration

Updated: May 21, 2022


The approved instrument referred to, in the case below, was sent out for a recalibration, a few days after the client's subject tests. We wanted to know WHY. What caused the need? Were consistently low cal. checks after the client's tests the reason? Were consistently low cal. checks before and after the client's tests the reason? Was there a significant change, over time, in the precision of the instrument, somewhere between March 6, 2015, April 14, 2015, and May 20, 2015?


Purposes of this cross-examination:


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."


To establish the need for an O'Connor order to produce the technicians' contemporaneous documentation that went with the periodic inspections of March 6, 2015, April 14th, 2015, and 20th of May 2015.

Q. So, I’m still looking at – going back to Exhibit 12 page 1. [Maintenance log of local police service for this Intoxilyzer]


Excerpt from Exhibit 12

A. Yes. Q. Periodic inspection concludes: "consistently low cal-checks. Requires recalibration." So, I – I’m just looking for where’s the data that could possibly – again, using the methodology for determining accuracy and precision, as defined by the Centre of Forensic Sciences, or as deemed by the Centre of Forensic Sciences, where’s the data that could possibly have supported consistently low cal-checks requires recalibration as a decision? A. That would be in the downloaded data that you have. There’s no hard copies that were provided.


Q. But in the download data that we looked at, there as nothing – again, using your deeming method – or, I’m sorry, the Centre’s deeming method in terms of checking accuracy and precision, there’s nothing there to indicate a problem with accuracy or precision, and certainly not a problem with accuracy and precision that would cause a need to send the instrument out for recalibration. A. You would have to ask the author of this document what he meant by that. Maybe he’s referring – if there’s nothing in the – there’s no additional information in the downloaded data, then maybe he’s referring to the consistently low calibration checks that are occurring during breath tests or stand alone calibration checks. Q. And we would need to see the data that was generated that went along with these periodic inspections of March 6, 2015, April 14th, 2015, and 20th of May 2015 in order to see if there was data that supported that decision. Try and figure out what it is that caused that decision that was made to take the instrument out of service and send it for recalibration by the manufacturer. A. That is correct.




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