Breathalyzer Defenses

There Are Many DUI Breathalyzer Defenses We Can Raise

Below are a few examples of Breathalyzer defenses that could be raised in a DUI breath test case. The examples listed are for use in detecting operator error in the operation of Breathalyzer Models 900 and 900A.

  1. Was the instrument properly warmed up?
    • To what temperature was the instrument heated prior to use?
    • For how long a period was the instrument allowed to warm up prior to use?
    • What was the temperature of the room or place where the instrument was stored prior to its use in this case?
    • When was the sample chamber thermometer checked by the operator?
  2. Were the operator’s hands clean while administering the test?
    • When and in what manner did the operator last wash his or her hands prior to the commencement of this test?
    • What substances were, or may have been, on the operator’s hands or fingers while operating the instrument during this test?
  3. Were the required sterilized implements properly installed?
    • Was a new, factory-sterilized, bubbler tube attached to the end of the delivery tube prior to the commencement of the test?
    • Was a new, factory-sterilized, mouthpiece attached to the intake tube prior to the taking of the breath sample?
    • Did the operator’s hands or fingers at any time come into direct physical contact with either of these implements?
  4. Were satisfactory ampoules properly selected and installed?
    • Where and in what manner were the ampoules stored prior to use?
    • What was the lot, batch, or control number of the test ampoule?
    • What was the lot, batch, or control number of the reference ampoule?
    • Was each ampoule gauged for both thickness and quantity of solution prior to use, and what did the gauging indicate?
    • Were there any smudges, smears, fingerprints, or other visual impediments on the glass of either ampoule?
    • In what manner was the top broken off of the test ampoule?
    • Did any foreign substances enter or come into contact with the solution in the test ampoule after its top was broken off?
    • Was the amount of solution in the test ampoule regauged after the top was broken off, and what did the gauging indicate?
  5. Was the bubbler tube properly installed?
    • After being inserted inside the test ampoule, was any part of the bubbler tube resting on or touching the bottom of the ampoule?
    • After being inserted inside the test ampoule, was the bubbler tube pointing toward or touching the glass on the side of the ampoule?
  6. Was the instrument properly purged with room air?
    • In what manner was room air forced into the instrument?
    • For how long a period was room air forced into the instrument?
    • For how long a period after the green “piston up” light came on was room air forced into the instrument?
  7. Was the instrument properly calibrated on room air?
    • Did the room air sample bubble evenly into the test ampoule?
    • For how long a period did the room air sample bubble into the test ampoule?
    • Was a 90-second reaction period observed immediately following the end of bubbling?
    • How long after the end of bubbling was the BAC of the room air sample recorded?
    • What BAC was reported on the room air sample?
    • In what manner was the instrument adjusted after the room air BAC was reported?
    • What were the results of any further tests run on room air samples and what further adjustments were made to the instrument?
  8. Was a proper sample of breath obtained for testing?
    • For how long a period, by whom, and in what manner was the defendant observed prior to the taking of a breath sample?
    • For how long a period did the defendant hold his or her breath immediately prior to exhaling into the instrument?
    • For how long a period did the defendant exhale into the instrument?
    • For how long a period after the green “piston up” light came on did the defendant continue to exhale?
    • Did any bubbling occur in the test ampoule while the defendant was exhaling?
  9. Was a proper reaction period observed?
      For a Model 900:
    • In what manner was the reaction period timed by the operator?
    • How long after the end of bubbling did the timed reaction period begin?
    • How long a reaction period was timed by the operator?
    • How long after the end of the timed reaction period was the BAC of the breath sample recorded?
      For a Model 900A:
    • How long after the “READ” light came on was the photometric light turned on?
    • How long after the “READ” light came on was the BAC of the breath sample recorded?
  10. Was the BAC of the breath sample properly measured?
    • When did the operator turn on the photometric light?
    • When did the operator begin to balance the galvanometer?
      * Note – In the Model 900A, the galvanometer is replaced by a null meter, which is operated in the same manner as a galvanometer.
    • How long did it take the operator to balance the galvanometer?
    • Where on the galvanometer scale was the galvanometer needle when the reported BAC was marked on the test record slip?
  11. Was the simulator test properly administered?
    • Was the breath testing instrument purged with room air in the manner described in (6) above?
    • Was the instrument calibrated on room air in the manner described in (7) above?
    • What type or model of the breath-alcohol simulator was used in the simulator test?
    • What was the alcohol concentration of the solution in the simulator, and how was the concentration ascertained?
    • When was the alcohol concentration of the simulator solution last tested prior to the defendant’s breath test, how was it tested, and who performed the test?
    • What was the simulator temperature at the time of the simulator test?
    • In what manner was the simulator hose connected to the intake tube on the breath testing instrument?
    • For how long a period after the green “piston up” light came on was the simulator hose connected to the intake tube?
    • Was a 90-second reaction period observed in the manner described in (9) above?
    • Was the BAC of the simulator sample measured in the manner described in (10) above?
  12. If more than one sample of the defendant’s breath was tested on the instrument, repeat (1) through (10) above for each sample tested.

These are only a few examples of how an attorney who specializes in DUI cases can begin to build Breathalyzer defenses for DUI breath test cases. If you or a loved one has been arrested for impaired driving and took a breath test, don’t feel your case is lost. The attorneys listed at TeamDUI.com work to WIN or reduce your case and provide the best legal services. Contact TeamDUI.com at 1-844-TEAM-DUI (1-844-832-6384) for a no-cost case evaluation with a DUI-DWI litigation lawyer today.

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