Picture this scenario: you’re driving down the Banksville Road when suddenly you see flashing lights in your rearview mirror. Even though you just had a drink or two, the police officer arrests you for driving under the influence (DUI). At the police station, a chemical breath test shows that you’re well above Pennsylvania’s legal limit of .08% blood alcohol concentration (BAC) for driving.
You know that you weren’t actually intoxicated. Could this be a situation where the machine got it wrong? False positive breath tests are a very real phenomenon. While there are a number of reasons that this can happen – including improper administration of the test – certain medical conditions can also lead to a false positive breath test.
To understand how this can happen, it is important to learn how breath tests work. While the science behind these tests is a bit complex, chemical breath tests basically measure the amount of alcohol in your breath and convert that number into a BAC.
These tests rely on deep lung air, which is closest to your blood supply. When a person takes a deep breath for a breath test, this air passes through the throat and mouth as they blow out into the machine. Some medical conditions may lead to the presence of mouth alcohol, which can skew the breath test results.
Below, we break down which medical conditions may lead to a false arrest for a DUI – and what you can do about it.
Digestive Disorders
Some digestive disorders can cause your body to produce mouth alcohol. In particular, gastroesophageal reflux disease (GERD) and acid reflux can cause stomach acids and/or alcohol to flow from the stomach back up into the esophagus. When this happens, a breath test may incorrectly register that you are drunk because your deep lung air picks up some of the alcohol as you exhale.
Other digestive disorders that may affect the results of a chemical breath test include hiatal hernias and heartburn.
Diabetes or Low Blood Sugar
A person who has diabetes or who has low blood sugar (hypoglycemia) may also lead to excessive mouth alcohol. This is due to the way that the human body breaks down fat, which results in a byproduct known as ketones. In diabetics, the body breaks down fat for energy instead of carbohydrates due to insufficient insulin (the hormone that helps deliver glucose to the rest of the body). Similarly, people who have hypoglycemia may also produce a lot of ketones as their bodies burn fat for energy.
A byproduct of ketone production is isopropyl alcohol. Excess ketones and isopropyl alcohol are excreted in the breath and in urine (which often gives off a “fruity” smell). Although this substance is different from ethyl alcohol – which is found in alcoholic beverages – it may still trick a breath test. At the same time, low blood sugar can cause a variety of symptoms, including confusion, blurry vision, sweating and anxiety – all of which may be mistaken for intoxication.
Some Diets
Cutting carbs is a popular way to lose weight. However, when a person stops eating carbohydrates, it can cause their body to produce ketones – just like what happens in a person with low blood sugar or diabetes. As a result, a person on a high protein, low carb diet or even someone who is on a crash diet may have a false positive breath test due to the secretion of isopropyl alcohol.
If you have been arrested for a DUI in Pittsburgh and believe that a medical condition or your diet may be to blame, you may be able to fight back against the DUI charge. By introducing scientific evidence and strong legal arguments, the charge against you may be dismissed or reduced.
