PAS Breath Test — The Roadside Test That Can Make or Break Your Case
The Preliminary Alcohol Screening (PAS) test is the handheld breathalyzer used roadside during a DUI stop. Most people don't know that you can legally refuse the PAS test if you're over 21 and not on DUI probation. And if you took it, the results are often unreliable.
PAS devices are screening tools, not precision instruments. We challenge their use at your APS hearing.
Challenging roadside breath test evidence
PAS ChallengesDevice ExpertsStatewideBilingual 🇺🇸🇲🇽PAS Test vs. Evidentiary Breath Test — Know the Difference
📱 PAS Test (Roadside)
- • Handheld portable device
- • Used BEFORE arrest as a screening tool
- • Less accurate — wider error margin
- • Can be refused by drivers 21+ (not on probation)
- • Often not properly calibrated
- • Affected by wind, temperature, mouth alcohol
🏢 Evidentiary Test (Station)
- • Desktop-grade machine or blood draw
- • Used AFTER arrest as official evidence
- • More accurate — stricter calibration requirements
- • Cannot be refused (implied consent applies)
- • Subject to Title 17 regulations
- • Controlled environment testing
Your PAS Test Rights
Over 21, No Probation
You CAN refuse the PAS test with no additional penalty. The officer must inform you of this right.
Under 21
You CANNOT refuse the PAS test. Zero tolerance law requires compliance. Refusal = automatic suspension.
On DUI Probation
You CANNOT refuse the PAS test. Probation terms require compliance with all chemical testing.
How We Challenge PAS Test Evidence
Device Calibration Records
PAS devices require regular calibration — often monthly. We subpoena the specific device's calibration history. Missed or late calibrations make the results inadmissible.
Environmental Factors
Roadside testing exposes the device to wind, temperature extremes, vehicle exhaust fumes, and other environmental contaminants. We document conditions that could affect accuracy.
Operator Error
Officers must follow specific procedures: proper observation period, correct number of samples, minimum wait time between tests. Shortcuts invalidate results.
Mouth Alcohol Issues
Recent drinking, burping, GERD, dental work, or even chewing gum can trap alcohol in the mouth and produce falsely high PAS readings. Without a proper 15-minute deprivation period, the result is unreliable.
Right to Refuse Was Not Communicated
If you're over 21 and not on probation, the officer must inform you that the PAS test is voluntary before administering it. If they didn't, we challenge whether your consent was valid.
Expert Help at a Fair Price
PAS test challenges require technical knowledge of device specifications, calibration standards, and testing protocols. We have the expertise — at a price that makes sense for your situation.
Free consultation • Flat-fee pricing • No hidden costs
Important: DMV APS California provides administrative hearing representation services. We are not a law firm and do not provide legal advice or criminal defense representation. For criminal DUI charges, please consult a licensed attorney. Our services are limited to DMV administrative hearings and related compliance assistance.
⚖️ Important: We are trained DMV Administrative Per Se (APS) hearing advocates and licensed insurance professionals — not attorneys. We do not provide legal representation. For criminal DUI defense, consult a licensed attorney.
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