Breathalyzer Tests in Arizona DUI Cases: Understanding the Process and Potential Challenges

Breathalyzer tests play a crucial role in Arizona DUI cases, providing law enforcement with a measurement of a driver’s blood alcohol concentration (BAC). However, these tests are not infallible and can be challenged under various circumstances. Understanding how breathalyzers work, the factors that affect their accuracy, and Arizona’s implied consent law can help those facing DUI charges build a strong defense.

How Breathalyzers Work

Breathalyzers estimate a person’s BAC by measuring the amount of alcohol in their breath. When alcohol is consumed, it enters the bloodstream and is eventually expelled through the lungs. The breathalyzer detects this alcohol and calculates an estimated BAC.

Common breathalyzer devices used in Arizona include:

• Intoxilyzer 8000 – A widely used device that measures infrared light absorption to determine BAC.
• Alco-Sensor FST – Often used for preliminary roadside testing before an official breath test at the police station.
• Intoxilyzer 9000 – A newer model with improved accuracy and digital record-keeping capabilities.

Challenging Breathalyzer Results

Although breathalyzer tests are considered scientific, various factors can compromise their accuracy. Here are some common ways to challenge breathalyzer results:

1. Machine Calibration and Maintenance Issues

• Breathalyzers must be regularly calibrated to ensure accuracy.
• If the machine was not maintained correctly or calibrated per regulations, the results may be unreliable.
• Maintenance logs can be examined to identify any inconsistencies or lapses in required upkeep.

2. Operator Errors and Testing Procedures

• Law enforcement officers must follow strict protocols when administering breath tests.
• Failure to observe the driver for the required period before testing (typically 15 minutes) may lead to inaccurate results.
• Improper training or procedural errors by the officer can compromise the validity of the test.

3. Medical and Environmental Factors

• Certain medical conditions, such as acid reflux or diabetes, can produce falsely high BAC readings.
• Residual mouth alcohol from mouthwash, breath sprays, or recent alcohol consumption can skew results.
• Environmental factors like exposure to chemicals (e.g., paint fumes or cleaning agents) may interfere with the test.

Arizona’s Implied Consent Law

Under Arizona’s implied consent law, drivers automatically agree to submit to a breath, blood, or urine test if arrested for DUI. Refusing a post-arrest breathalyzer test carries serious consequences:

• First refusal: 1-year driver’s license suspension.
• Second refusal (within 84 months): 2-year driver’s license suspension.
• Additional penalties: The refusal can be used as evidence against the driver in court.

However, officers must follow proper procedures when requesting a breath test, including informing the driver of the legal consequences of refusal.

Conclusion

Breathalyzer tests are a common tool in Arizona DUI cases, but they are not foolproof. Understanding how they work, their potential flaws and the impact of implied consent laws can be critical in challenging a DUI charge. Consulting an experienced DUI defense attorney can help identify weaknesses in the prosecution’s case and build a strong defense strategy.