top of page

Index to Tips for Discussion by Defence Lawyers

Updated: Aug 31, 2022

Tips for Defence Lawyers and Attorneys in Challenging the Reliability of Approved Instruments, Alcohol Standards, and Accessory Equipment such as Simulators and Simulator Thermometers

  1. Ask for disclosure of the serial number of the simulator used by the qualified technician during your client's approved instrument breath tests.

  2. Find out how many simulators were in use or available at the police detachment about the time when your client was being tested.

  3. Purchase a copy of the "Model 2100 Simulator Operational Manual" published by Guth Industries.

  4. Simulators are "accessory equipment" in the ATC recommendations and so they must be inspected annually to ensure that they "continue to meet the manufacturer's specifications".

  5. The manufacturer's specifications for a Guth 2100 simulator require that it maintain a temperature of 34.0 ±.05° C. An inspection verifying 34.0 ±.2° C. is not proof of compliance with manufacturer's specifications.

  6. The Centre of Forensic Sciences in Toronto recommends that a NIST mercury thermometer be used whenever police use the digital display on a Guth 2100 or 10-4D simulator.

  7. A diligent defence lawyer should find out the Standard Operating Procedures (SOPs) of the local police service respecting verification of the digital temperature display on the simulator.

  8. Learn Henry's Law in science. An understanding of Henry's Law is an essential tool for cross-examining a breath tech.

  9. Find out if police in your jurisdiction are using an RS232 interface between the Intoxilyzer® 8000C and the Guth 2100 simulator.

  10. A police officer using a Guth 2100 simulator can make use of up to three different simulator thermometers. Which one(s) did the officer use with your client?

  11. Which is more trustworthy: a digital thermometer or a mercury thermometer?

  12. When a new mercury thermometer is shipped to the police, the mercury column may separate in the upper bulb.

  13. Sometimes during use, the mercury column in the lower contraction chamber can separate.

  14. When police purchase a new mercury thermometer, they receive a Certificate of Calibration from Guth.

  15. The CFS 8000C Training Aid recommends that simulator tubing be short.

  16. It is very difficult for a qualified technician to read the mercury thermometer from a sitting position in front of the Intoxilyzer® 8000C attached to the Guth 2100 in the CFS recommended position.

  17. Always be specific about the thermometer to which you refer in a Stinchcombe letter.

  18. A Guth 2100 simulator will frequently indicate a digital display temperature of 33.9, 34.0 or 34.1. It is not always 34.0.

  19. COBRA data may reveal that a police service too frequently records temperatures at exactly 34.00.

  20. A local police service owns a simulator which had a perfect record of 34.00 temperature stability in 2012 and 2013.

  21. Six to eight months of seeing the same numbers can lead to the temptation to always record exactly 34.0.

  22. Defence lawyers should study COBRA data for clusters of low climbing cal checks at 3400.

  23. COBRA data of simulator temperatures such as 33.95 or 33.99 are indicative of use of an RS232 interface.

  24. Defence lawyers need to study the function of each of the Guth 2100 simulator probes.

  25. Study the block diagram at page 13 of the "Model 2100 Simulator Operational Manual". Notice that the digital thermometer does not appear to be independent.

  26. Defence lawyers need to understand the differences among the concepts: "calibration", "calibration check", and "inspection".

  27. Find out if the Inspector used a traceable reference thermometer, precise to at least 2 decimal places, when inspecting the Guth 2100 simulator.

  28. Make inquiries about chips and cracks in the simulator jar.

  29. If the glass jar of the simulator is screwed too tightly into the upper housing, the jar can develops chips and cracks.

  30. Appendix E of the CFS 8000C Training Aid recommends anecdotal notes in the Alcohol Standard Log. Anecdotal notes are useful in finding problems with jar tightness or bad seal.

  31. Disclosure of location changes of the DUI simulator between alcohol standard change and subject breath tests is essential to full answer and defence.

  32. A defence lawyer needs to gather COBRA data respecting changes of location in close proximity to the subject tests. The "best evidence" of location of the Intoxilyzer 8000C / Guth 2100 simulator combination over a series of days, prior to and after the subject tests, is the electronic record "location" field, initially stored in the 8000Cs short term memory, then automatically saved to a dbf file within the 8000C.

  33. In late 2013 and early 2014, some Ontario Police Services, starting with the OPP, began using COBRA V software, instead of COBRA IV software, to extract COBRA data from their Intoxilyzer 8000Cs.

  34. The use of an alcohol standard during evidentiary breath testing in Canada is not mentioned as a condition precedent to section 258(1)(c) but it seems that everyone in the judicial system and the scientific community in Canada assumes it is a condition precedent.

  35. One method of controlling continuity between alcohol standard change and subject breath tests is to write the date and time of change on the empty bottle and then leave the bottle on the desk. It is not a good method.

  36. Another method of controlling continuity is to write the details of the alcohol standard change on a whiteboard or blackboard. It is not a good method.

  37. Another method of controlling continuity is simply to look at the box containing yet unused alcohol standard bottles in order to get details of expiry and lot number. It is not a good method.

  38. Another method of controlling continuity is to write details on an alphanumeric seal and then attach the seal between the jar and the housing. Each officer using the alcohol standard records the seal number in his or her notebook and checks the seal number in the alcohol standard log.

  39. Be sure to check the alcohol standard log to determine if the outgoing seal number one week matches the incoming seal number the next week.

  40. The CalGuard feature in the Intoxilyzer® 8000C has limitations. It does not render an alcohol standard log unnecessary.

  41. Changing breath room ambient conditions can reduce wet-bath alcohol standard /simulator reliability.

  42. A functioning ambient fail system in the approved instrument is necessary for reliability of the alcohol standard / simulator system.

  43. A functioning air blank system in the approved instrument is a condition precedent to reliability of a cal. check.

  44. I suggest a qualified technician can deliberately or negligently compromise the air blank, ambient fail, and zero adjust systems on an approved instrument by placing the breath tube under the instrument.

  45. Alcohol in a simulator or on a person's breath can be made to disappear as a result of ambient air conditions in the breath room. That is a result of the zero adjust system on an IR instrument. It is normal functioning of an IR instrument. That zero adjust system, combined with the ambient fail system, is necessary on an IR approved instrument for a reliable result. It is the environmental conditions in the room that are affecting the results. Modern IR systems have safety features that are supposed to flag such environmental problems. That system doesn't work properly if the instrument is manipulated in such a way as to disable zero adjust / ambient fail. Error will not be flagged or apparent if those systems have been compromised. An unreliable cal. check or subject test may occur with no error flag.

  46. An "ambient fail" is a normal exception in a functioning approved instrument and is a flag that tells a conscientious qualified technician that something is wrong with his or her operation of the instrument, i.e. something is wrong with the environment in which the instrument is being used.

  47. A calibration check using a wet-bath or dry gas simulator is not reliable, not probative, if information about air blanks is not available.

  48. The reliability of the alcohol standard may be compromised by the presence of an interferent in the air.

  49. It is very possible to have 02 agreement, yet the results of the approved instrument and/or the alcohol standard in the simulator are not accurate or not reliable.

  50. Calibration of the ethyl alcohol quantification system in an approved instrument is not linear; it is a curve.

13 views0 comments


bottom of page