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Writer's pictureStephen Biss

Police No Longer Follow ATC Best Practices Respecting Tolerance

Updated: May 1, 2022



Purpose of this sample cross-examination:


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.

Q. All right, if we could turn please, to Exhibit Number 12? That’s the document with some of the records from [local] Police. And I think I may have to have [thje Crown expert] look on mine. First of all, page 9. February 15th, 2011, an inspection done by an entity called Thomas – I think it’s Thomas Electric. A. Yeah. Q. And specifically, in that document it appears that the inspector, the person conducting this inspection, whoever it is, working for Thomas Electric, it appears that they were checking linearity of the instrument at – and accuracy of the instrument, at a number of different values, but the range of values that we’re going to be – which were considered acceptable were plus or minus 3 milligrams per


100 mils. Have I got that right? A. That's correct. Q. And that’s across the board. That’s with respect to 40 solution, 80 solution, 100 solution, and... A. 300 solution. Q. ...300 solution. At each of those values. A. Yes. Q. So, they’re checking it at plus or minus 3 milligrams per 100 mils. Now as I recall, that range of 3 milligrams per 100 mils is similar to the manufacturer’s specifications for the accuracy of the Intoxilyzer 8000 or 8000C that we looked at earlier. A. Was it the manufacturer’s specifications or their brochure? Q. Let me just find the exhibit and we can check. THE COURT: Is that Exhibit 24, the.... MR. BISS: I think it’s Exhibit 25 Your Honour.

MADAM CLERK: Exhibit 25 is the excerpt from C.M.I. Incorporated, the manual. MR. BISS: At page 2, Exhibit 25, page 2. A. Yes. Q. So, Thomas Electric, it would appear, confirmed that at each of those values, to put it in another way, the instrument was reading 40 milligrams per 100 mils as being 40 milligrams per 100 mils plus or minus 3 percent. A. Three. Q. Plus or minus 3 milligrams or plus or minus 3 percent? A. It doesn’t give the units, actually. Q. All right. A. It says plus or minus .003. I think we can


safely assume that that’s 3 milligrams. So, the result is between 37 and 43 for the 40.

Q. All right. So, next step in my question is, in the best practiced document of the Alcohol Test Committee, that would be what was Exhibit 11 in our matter, the same page that my friend asked you about this morning, here we go, page 11. The indication there that under inspection, that all approved instruments included for active use in the program shall be individually inspected before being placed into service and periodically thereafter, to ensure that they initially meet and continue to meet the manufacturer’s specifications. That’s the recommendation. A. That’s what it says, yes. Q. From the Alcohol Test Committee. And that recommendation and the inspection report from Thomas Electric are consistent with each other because – I’m not sure tolerance is the right word – but the – the – Thomas Electric seems to be using the manufacturer’s specifications of plus or minus 3 as its acceptable or unacceptable interval within which to assess the accuracy of the instrument at each of the values. A. Yes. Q. But if we turn now to some other reports, so for example at page 10 of the same document, which I’ll show you in a moment, that’s in the document that is Exhibit 12, it appears now that [local] Police was the entity that was doing the periodic inspection. A. Yes.

Q. The date of it will be on the opposite page, I think. I think it was June the 1st, 2011. A. June 1st, 2011, yes. Q. The tolerance that [local] Police was


looking at on page 2 of the same.... A. Page.... Q. Yes, I’m sorry, page – page 10 which is page 1 of 2. The tolerance that they were looking at was now 10 milligrams per 100 mils. A. Plus or minus 10 percent. Q. Plus or minus 10 percent. A. Ten percent of the target, yes. Q. All right, and if we look at the rest of the documents that have come from [local] Police, it appears that [local] Police, in its periodic inspections has been checking the instrument at plus or minus 10 percent. You can do that if you like, and check each of them, but... A. I was just.... Q. ...June the 20th is at – June 20th, 2012 is page 28. A. So I’m assuming that each of these is a single test. Right? So when we look at the Thomas Electric Security Limited... Q. Yes. A. ...test procedure checklist. Q. Yes. A. Check sheet. I’m assuming that each of these are one test possibly using the same standard? Q. Yes. A. I don’t know, you’d have to.... Q. I don’t – we don’t – we don’t know that. A. We don’t know that, yeah. Q. Of course, we don’t have that information. This is the – this is at page 9. A. Yes. So we don’t know if that was run – one standard was run several times to get that result or


that... Q. Yes. A. ...any of the more average.... Q. Yes. A. Right. Q. But it appears that [local] Police, in running its same test – similar tests at 50, 100, and 300 milligrams per 100 mils has now changed the inspection from instead of the manufacturer’s specifications of plus or minus 3 has now shifted it to plus or minus 10 percent. A. Yes, correct. The same as the – the value that’s used for the calibration check. Q. So, the checks now, beginning on June the 1st, 2011 are no longer in relationship to the manufacturer’s specifications but have now changed to the plus or minus value that the Centre of Forensic Sciences recommends. A. That's correct. Q. So, this is no longer a check to see if the linearity of the instrument is good in accordance with manufacturer’s specifications, it’s – these are only calibration checks in accordance with the recommendations of the Centre of Forensic Sciences, which as I understand, just apply to 100 milligram per 100 mil solution. A. That's correct. You’d have to ask [senior breath tech] from the [local] Police why he chose


to change the standard. I believe most inspection reports that I’ve seen, whether it’s the O.P.P., Toronto Police Service, they tend to use the same target value of plus or minus 10 percent but the values that were obtained here, appear to be within the plus or minus 3 percent or 3 milligrams. Q. All right, so as of June the 1st.... A. Other than the result – sorry – other than


the result of 96.Q. Yes. So, as of June the 1st, 2011 the instrument, based on the values


that you can see there on page10, the instrument is still performing, when having a


calibration check at each of these values of 50, 100 and 300 is still performing in accordance


with the manufacturer’s specifications with respect to accuracy.


A. That's correct. And so, therefore, the linearity has been maintained.

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