DUI Defenses That Work
Being charged with a DUI does not mean you will be convicted. Arizona prosecutors have the burden of proving every element beyond a reasonable doubt. That standard is high, and DUI cases are full of opportunities for the defense.
The defenses below are not theoretical. They are strategies that get used in Arizona courtrooms every week and produce real results—dismissed charges, suppressed evidence, reduced convictions, and acquittals at trial. We have personally employed every single one of them.
Challenging the Traffic Stop
The Fourth Amendment requires reasonable suspicion. If the defense can show the officer lacked it, all evidence gathered after the stop may be suppressed.
We once got a full suppression because the officer’s own dashcam showed our client driving perfectly within the lane for two minutes before the stop. The officer wrote “observed weaving” in his report, but the video told a different story.
Challenging BAC Test Results
The BAC number is the centerpiece of most DUI cases. Breath tests are vulnerable to calibration issues, operator error, observation period failures, and medical conditions. Blood tests are vulnerable to chain of custody failures, improper preservation, and laboratory error. Independent retesting frequently produces different results.
Rising Blood Alcohol Defense
After your last drink, BAC continues to rise for 30–90 minutes. If tested well after the stop, your BAC at testing may have been higher than at the time of driving. A BAC of 0.16 at testing might have been 0.12 while driving—the difference between an extreme DUI and a standard DUI, or even below the legal limit.
Actual Physical Control
Arizona courts use a “totality of the circumstances” test. Factors include whether the engine was running, where the keys were, whether the vehicle was parked, whether the person was in the driver’s seat, and whether they appeared to be sleeping. If the evidence suggests you were sleeping it off, this defense can be very effective.
Constitutional Violations
The Fourth, Fifth, and Sixth Amendments all come into play. Miranda warnings, warrantless blood draws, and denial of access to counsel can all affect the admissibility of evidence.