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How Accurate Are Chemical Tests for DUI?

police officer looking at woman's license while she holds breathalyzer in driver's seat

How Accurate Are Chemical Tests for DUI?

Breath, blood, and urine tests are taken as evidence for DUI of alcohol and drug cases. Did you know, though, that there are many factors that could make these test results inaccurate? Let’s discuss some of the ways chemical tests may fall short.

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Breathalyzer Results

1. Medical Conditions

Some medical conditions can affect accurate breath test readings.

Digestive disorders may cause your stomach contents to travel back up through your esophagus, pushing the presence of alcohol into your breath.

Individuals with diseases that affect blood sugar are also at risk of getting inaccurate BAC results. This is due to fat in the body turning into ketones, which in turn causes the liver to produce acetone that can be detected as drinking alcohol during a breath test.

Some examples of these disorders include:

  • Acid reflux
  • Diabetes
  • Heartburn
  • Hypoglycemia

2. Mouth Alcohol

Mouth alcohol refers to a small amount of alcohol stuck in one’s mouth or throat that can be detected during a breath test. This may be from alcohol stuck in food between the teeth, or even alcohol content from recently used mouthwash.

Breath tests may pick up on this residual alcohol in the mouth, leading BAC to appear higher than it is.

3. Device Errors

If the breathalyzer malfunctions or is not properly calibrated, it could lead to inaccurate readings. Thousands of DUI cases have been fought and won after proving that the breathalyzer was not properly maintained and drivers were being inaccurately charged with driving under the influence.

Blood Tests

Blood tests are generally known to be more accurate than breath tests. Still, there are reasons why blood test results may not paint an accurate picture for DUI. First, if the sample is stored improperly, it can affect the results. In some conditions, the blood sample could ferment, causing the BAC reading to be high. Additionally, the wrong person’s sample could have been tested and used as evidence due to a lab mixup.

Jacksonville DUI Lawyers

Think again if you feel you can’t fight your DUI charges because you blew above the legal limit. Our team at First Coast Criminal Defense knows that chemical test results are not always accurate, and we can create a creative defense on your behalf. Call us at (904) 474-3115 to speak with one of our Florida DUI defense attorneys.