Defending against a DUI (Driving Under the Influence) charge is a serious and complex legal matter, but several common defenses can be employed depending on the specifics of the case. These defenses aim to challenge the validity of the prosecution’s evidence or to assert that the defendant’s rights were violated during the arrest process.
Challenging The Traffic Stop
One of the most fundamental defenses in a DUI case is challenging the legality of the traffic stop that led to the arrest. Under the Fourth Amendment, law enforcement must have reasonable suspicion or probable cause to stop a vehicle. If the police stopped the driver without a legitimate reason—such as observing a traffic violation or erratic driving—the stop may be deemed unlawful.
For example, if a driver was pulled over merely because they were driving late at night or in a certain neighborhood without any indication of illegal activity, the defense could argue that the stop was unjustified. If the court agrees, any evidence gathered after the stop, including breathalyzer results or field sobriety test observations, may be suppressed, significantly weakening the prosecution’s case.
Questioning The Accuracy Of Field Sobriety Tests
Law enforcement commonly uses field sobriety tests (FSTs) to establish probable cause for a DUI arrest. However, these tests are subjective and can be unreliable. A defense attorney might argue that the FSTs were improperly administered or that external factors, such as poor road conditions, bad weather, or the defendant’s physical or medical conditions (e.g., balance issues, anxiety), affected the results.
For instance, if a driver fails a walk-and-turn test but was wearing high heels or was on uneven ground, their performance might not accurately reflect impairment. Additionally, a person with a medical condition that affects balance could perform poorly on FSTs despite not being impaired. Questioning the validity of these tests can cast doubt on the prosecution’s evidence.
Challenging Breathalyzer Or Blood Test Results
Breathalyzer and blood test results are critical pieces of evidence in most DUI cases, but they are not infallible. There are several ways to challenge the accuracy of these tests:
- Calibration and Maintenance of Equipment: Breathalyzers must be regularly calibrated and maintained to produce accurate results. If the device used in the defendant’s case was not properly calibrated, the results could be inaccurate.
- Improper Administration: The officer must follow specific protocols when administering a breath test. Failure to adhere to these protocols—such as not observing the defendant for the required time before testing—can result in unreliable results.
- Medical Conditions and Substances: Certain medical conditions, such as acid reflux or diabetes, can affect breathalyzer readings. Additionally, substances like mouthwash or medications can contain alcohol or interfere with the test, leading to falsely elevated readings.
Challenging the accuracy of these tests can be a powerful defense, especially if the breathalyzer result is close to the legal limit.
Rising Blood Alcohol Concentration (BAC) Defense
The rising BAC defense is based on the idea that a driver’s blood alcohol level may have been below the legal limit while they were driving but rose to an illegal level by the time they were tested. Alcohol takes time to be absorbed into the bloodstream, so if a person drinks shortly before driving, their BAC might still be rising when they are pulled over.
For example, if a driver consumed alcohol shortly before being stopped and their breathalyzer test occurred an hour later, their BAC might have increased during that time, resulting in a reading above the legal limit even though they were under the limit while driving. This defense is particularly relevant when there is a significant delay between the traffic stop and the BAC test.
Defending against a DUI charge requires a detailed examination of the circumstances surrounding the arrest and the evidence collected. Common defenses include challenging the legality of the traffic stop, questioning the accuracy of field sobriety and breathalyzer tests, and using the rising BAC defense. Each case is unique, and a successful defense often hinges on the specific facts and the ability of a DUI lawyer to challenge the prosecution’s evidence effectively.
Thanks to our friends at May Law, LLP for their insight into DUI cases.