False Positives from DUI Tests: Knowing Your Legal Options

James Novak

The people of Phoenix have a strong advocate in our law firm. We offer expert DUI defense strategies, always focused on providing clients with fair hearings and proper legal consideration from the authorities.

While law enforcement relies on technology to make assessments of sobriety, sometimes their DUI tests are flawed and inaccurate. A breathalyzer test, for example, may result in a false positive and an unjust drunk driving arrest. Let’s explore the issue in more detail.

What Is a False Positive?

In basic terms, a false positive is a test result that wrongly indicates that a condition is present when it is not actually present. In the case of DUI and sobriety tests, this means that the test you have taken incorrectly finds that your BAC is above the legal limit when it is actually still within the legal limit.

What Kinds of DUI Tests Can Result in a False Positive?

All kinds of DUI tests can lead to false positives. This includes blood, breath, and urine tests. Some of the most common false positives are linked to breathalyzer tests, however. This makes sense since breath is a highly unreliable way to measure the amount of alcohol in a person’s bloodstream.

Causes of False Positive DUIs

There are numerous reasons why false positives may occur with sobriety tests. Some of the most common causes of false positives include:

  • Improper Equipment Calibration – When a breathalyzer test is not properly calibrated, this could lead to wildly inaccurate or inconsistent readings with regard to BAC.

  • Diet Issues May Affect Results – People who are on low-carb diets or have certain dietary practices may have increased levels of acetone present on their breath. Breathalyzer tests may read the acetone as alcohol.

  • Medical Conditions and Medications – Cases of heartburn and acid reflux have been known to procedure elevated BAC results in breath tests. If you are on any medications, this can also lead to issues with DUI test accuracy.

  • Timing of the Test – Timing is crucial when it comes to DUI tests. For breath tests, if you vomit or drink within 15 minutes of taking a breathalyzer, your BAC may show up higher. Similarly, blood and urine tests may yield different results depending on when samples are taken and when your last drink or trip to the restroom occurred.

  • Environmental Contamination of Samples – If any sample is contaminated by other objects in the environment, it can potentially result in a false positive or an inaccurate result regarding BAC.

  • Poor Sample Storage Practices – Blood and urine samples stored for a long period of time or at certain temperatures can affect the results of lab analysis.

  • Errors in the Lab – When analyzing blood or urine samples in the lab, various kinds of human error can lead to false positives and generally incorrect test results.

Challenging a False Positive DUI

Challenging a false positive can prove difficult. In order to fight a false BAC reading, you need skilled legal help, such as a DUI defense attorney who has expertise when it comes to inaccurate tests and readings. In a number of cases, challenging a false positive DUI is a way to have charges dropped and penalties reduced if not eliminated outright.

If you feel that you have been unjustly accused of driving while under the influence of alcohol, it’s important to speak with a skilled defense attorney about your case.

Speak with an Experienced DUI Attorney

To learn more about your legal options following a false positive on a DUI test, be sure to contact an experienced DUI defense attorney today. Our team of legal experts will fight to ensure you receive a fair shake from the authorities.

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About James E. Novak

James E. Novak participates in several legal organizations including The Arizona Attorneys For Criminal Justice, The Association of Trial Lawyers of America, and others.

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