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What Causes Unreliable Breathalyzer Results?

What Causes Unreliable Breathalyzer Results?

What Causes Unreliable Breathalyzer Results?

When facing a DUI charge, your BAC (blood alcohol concentration) can mean the difference between a felony and a misdemeanor. Under California’s Implied Consent Law, all motor vehicle operators are required to submit to a chemical test (such as a breathalyzer test) if they are pulled over and suspected or drunk or drugged driving.

However, you may be surprised to know that the breathalyzer and other chemical tests are not always accurate. There are various conditions in which a breathalyzer test may result in an inaccurate reading of your BAC and potentially lead to unjust consequences in court.

If you were recently charged with a drunk or drugged driving offense, it’s essential to know your rights. A DUI conviction—especially if you have accrued prior offenses—can lead to serious penalties, including prison time, fines, and even a felony conviction.

Keep reading to learn common reasons why a chemical test alone usually isn't sufficient evidence for a DUI conviction in the California court.

Errors in DUI Breath Tests

There are certain steps that must be followed when an officer conducts a chemical or breathalyzer test. While drivers are required to consent to a chemical test when pulled over and suspected of drunk driving by a law enforcement official, it turns out these chemical tests aren’t always accurate.

Certain conditions are known to inflate or reflect inaccurate breathalyzer readings. In this case, the results and penalties of a given criminal case may be drastically altered. If your your initial reading was over the legal limit of 0.08% but that result is proved to be false, this could have positive implications for your case.

If you’re facing DUI charges and suspect that your breathalyzer reading was inaccurate, it’s critical to consult with a trusted criminal defense attorney to help determine the most effective legal strategy for your case.

Here are some common reasons why a DUI breathalyzer reading may produce inaccurate results:

#1. The officer didn’t conduct the appropriate 15-minute observation period.

Police officers are required to observe an individual suspected of drunk driving for a minimum period of 15 minutes. This is intended to prevent residual alcohol (commonly referred to as “mouth alcohol”) from affecting the breathalyzer reading.

Residual alcohol in your mouth can result in a falsely inflated BAC level. The law enforcement official is required to observe you for at least 15 minutes to ensure that 1) you don’t regurgitate, which can result in an inaccurate reading due to mouth alcohol, or 2) ingest additional substances during the 15-minute time window.

#2. You have a medical condition or diet that falsely inflated your BAC.

Certain medical conditions are known to inflate your blood alcohol concentration. Examples include diabetes, hypoglycemia, or a high protein diet can result in a falsely inflated BAC reading. This is due to your liver producing ketones that are excreted in your breath.

#3. The breathalyzer test was administered as part of an illegal search.

For a breathalyzer reading to be considered valid evidence in a criminal case, the officer who pulled you over must have had probable cause to do so. If the law enforcement official who pulled you over lacks probable cause, this can be a powerful defense in court, as it can result in certain evidence being dismissed from the legal proceedings.

#4. The breathalyzer wasn’t calibrated to provide an accurate reading.

Like all equipment, the breath test device isn’t immune to errors or system malfunction. For accurate results, the breathalyzer must be regularly calibrated. When used frequently without calibration, the test may be prone to inaccuracies. Unless law enforcement regularly checks for this issue, it’s impossible to know if the device was working properly.

How Does a BAC Reading Affect a Criminal Case?

Additionally, variances in human physiology can result in some individuals having inaccurate chemical readings. From a legal perspective, it’s impossible to prove guilt on the basis of one chemical test. Regardless of whether the breathalyzer device was functioning properly, the breath test alone is unlikely to determine the final outcome of your case.

Fortunately, there are various legal defense strategies you can employ to obtain a favorable outcome in court. It’s imperative to first secure the support of an experienced legal defense attorney who can assess the unique details of your case and establish the best path forward.

Award-Winning Criminal Defense in Oakland

Our firm understands how overwhelming it can be to find yourself on the wrong side of criminal law. Rest assured that our justice system is designed to protect your right to a fair trial regardless of the accusation you’re facing.

Our Oakland criminal defense attorney has successfully helped hundreds of clients achieve acquittals or dismissals for various criminal charges, from DUIs to drug crimes to theft. If you’re facing a criminal offense in California, don’t settle for less than the Bay Area’s top criminal defense attorney.

Criminal charges entail life-altering repercussions that can be severe. Don’t leave your future up to chance. Call the Law Office of Nabiel C. Ahmed at (510) 907-6600 today to schedule a free consultation.