Challenging Blood and Breath Test Results Losing Your Freedom Is Not an Option

Challenging Blood and Breath Test Results

Your case may hinge on the chemical test – which can be a breath test, a blood test or, in rare cases, a urine test. Challenging the reliability and accuracy of chemical test results is a hallmark of our practice. Our DUI attorneys have a reputation for winning victories based on challenging the reliability of blood and breath test results, tests and the machines used to conduct the testing, and demonstrating issues in the laboratories where the test were performed. Our efforts have resulted in:

  • The suppression by the trial court of all blood test results in 11 felony cases, after the judge found them to be unreliable at the conclusion of a 17-day-long challenge to their admissibility.
  • Removal of the Intoximeters RBT-IV® machine from the streets of Arizona.
  • Suppression of test results in more than 7,000 cases based on our challenge to the Intoximeters RBT-IV.
  • Suppression of test results and dismissal of cases throughout Arizona because of our demand for the CMI Intoxilyzer 8000® source code and software.

We routinely challenge the manner in which blood test are conducted in Arizona. Our work has exposed a history of significant issues with the blood testing equipment used in crime laboratories throughout Arizona. This includes:

  • The equipment used to test blood in the Scottsdale Crime Laboratory from 2009-2015 misprinted the names of the samples it was testing, and the vial numbers of the samples it was testing, and would stop collecting information in the middle of testing a blood vial from time to time.
  • In 2013, a blood testing device used in the Phoenix Department of Public Safety (DPS) laboratory had an issue that produced a false peak in all test results, requiring the lab to rebuild the machine from scratch.
  • After the rebuilt machine was put back in service in 2014, incorrect calibration values were used to test blood 62 times in a row with no one in the lab noticing.
  • In June 2015, DPS wrote to the manufacturer of the blood testing equipment that it used, PerkinElmer, complaining that the equipment “intermittently and unpredictably mislabeled the vial number that was injected on result printouts,” and demanded that the company create a plan to repair the equipment within 10 days, or refund the $376,668.90 DPS had paid for the equipment.
  • In October, 2015, after PerkinElmer had supposedly repaired the equipment, an incorrect vial number was reported for the sample being tested on one of the test runs. The test runs, of course, were designed to show that the problem had been eliminated.
  • To this day, the blood testing equipment use in DPS laboratories throughout Arizona still routinely misprints the vial numbers of the samples being tested (this occurred, for example, in 3 out of the 6 blood runs conducted by the Tucson DPS lab in June, 2018).

We also routinely challenge breath test evidence, demonstrating to judges and juries how a breath test can be artificially inflated by up to 34% by:

  • Breath and body temperature
  • Breathing patterns
  • Physiological variables unaccounted for by the testing equipment
  • Mouth alcohol
  • Machine error
  • False assumptions the machine makes about the rate at which alcohol is exchanged between the subject’s breath and blood (the partition ratio)


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