7 Defenses to Common Evidence Used in DWI Cases

Driving while intoxicated (DWI) is a serious offense in Texas that can result in severe legal penalties, including fines, license suspension, and even jail time. If you are facing a DWI charge, it is crucial to understand the evidence that may be used against you in court.

While your arresting officer may have had you undergo tests, gathered video evidence, or even reported that you admitted to being under the influence, there are several ways in which you can have that evidence thrown out or made inadmissible in the courtroom. Having an intelligent and diligent Killeen DWI defense attorney can help to ensure that you do not face penalties for a crime for which you were improperly charged or tested.

1. Field sobriety tests

Field sobriety tests (FSTs) are commonly used by police officers to determine if a driver is under the influence of alcohol or drugs. These tests typically include the horizontal gaze nystagmus (HGN) test, walk-and-turn test, and one-leg stand test. During the HGN test, the officer will ask the driver to follow a pen or flashlight with their eyes while the officer observes. The walk-and-turn test requires the driver to walk heel-to-toe in a straight line, turn, and then walk back. The one-leg stand test requires the driver to stand on one foot for a certain period. However, FSTs are not always accurate, and many factors can affect a driver’s ability to perform these tests, such as physical disabilities, medical conditions, and nervousness.

A skilled defense lawyer can challenge the accuracy of FSTs in court by arguing that the officer did not administer the tests correctly or that other factors, such as poor lighting or uneven terrain, affected the driver’s performance. Additionally, a Killeen defense lawyer may be able to argue that the FST results were not reliable due to the driver’s physical condition or other factors.

2. Breath tests

Breath tests, also known as breathalyzers, are another common form of evidence used in DWI cases. These tests measure the level of alcohol in a driver’s breath and provide an estimate of their blood alcohol concentration (BAC). However, breath tests are not always reliable and can be affected by a variety of factors, such as the temperature of the breath, the presence of mouth alcohol, and other substances in the mouth.

A skilled defense lawyer can challenge the accuracy of breath tests by arguing that the machine was not calibrated correctly, that the officer administering the test was not properly trained, or that other factors affected the test results.

3. Blood tests

Blood tests are the most accurate form of BAC testing and are often used in DWI cases when a driver refuses to take a breath test or when the results of a breath test are in question. However, blood tests are not infallible and can be affected by factors such as the storage and handling of the sample, contamination, and errors in the testing process.

A skilled defense lawyer can challenge the accuracy of blood tests by arguing that the sample was mishandled, that the testing equipment was not properly calibrated, or that the lab made mistakes during the testing process.

4. Field observations

In addition to FSTs, police officers may rely on their observations of a driver’s behavior, speech, and appearance as evidence of intoxication. For example, an officer may note that the driver had bloodshot eyes, slurred speech, or smelled of alcohol. While these observations can be used as evidence in a DWI case, they are often subjective and can be challenged in court. Police officers can also be influenced by their own personal biases before, during, and after they pull you over.

A skilled defense lawyer can challenge field observations by arguing that the officer’s perceptions were inaccurate or that the driver’s behavior was the result of factors other than intoxication, such as fatigue or medication.

5. Video evidence

Video evidence is becoming increasingly common in DWI cases, as many police vehicles are now equipped with dashboard cameras and officers often wear body cameras. Video evidence can be extremely valuable in defending against DWI charges, as it can provide a visual record of the events leading up to an arrest. Video evidence can capture the manner in which a defendant was driving, any field sobriety tests that were administered, and the defendant’s interactions with the arresting officer.

However, video evidence is not always reliable. For example, a dashcam video may not accurately capture the driver’s behavior due to a poor angle or low lighting. Similarly, body cameras can be obstructed by clothing or movement, or may not capture the entire interaction between the defendant and the officer. Additionally, police officers may not always turn on their body cameras, which could lead to gaps in the video evidence.

Your defense lawyer may be able to challenge the admissibility of video evidence by demonstrating that it is unreliable or that it was obtained in violation of your constitutional rights. For instance, if the arresting officer did not have a valid reason to pull you over, any video evidence that was obtained during the stop may be inadmissible. Similarly, if the officer failed to administer field sobriety tests in accordance with established standards, any video evidence of those tests may be subject to challenge.

In some cases, your defense lawyer may be able to argue that the video evidence should be suppressed based on the “fruit of the poisonous tree” doctrine. This doctrine holds that evidence that is obtained as a result of an illegal search or seizure is itself inadmissible. For example, if the officer illegally stopped you and then obtained video evidence of your conduct during the stop, that evidence could be suppressed as fruit of the poisonous tree.

6. Challenge the legality of the traffic stop

In order to stop a driver on suspicion of DWI, a police officer must have reasonable suspicion that the driver is engaged in criminal activity. If the officer lacked reasonable suspicion or if the traffic stop was conducted in violation of the driver’s constitutional rights, any evidence obtained as a result of the stop may be inadmissible. A defense lawyer can challenge the legality of the traffic stop and argue that any evidence obtained thereafter should be suppressed.

7. Challenge the admissibility of incriminating statements:

If a driver makes incriminating statements during the course of a DWI investigation, those statements may be used as evidence against them in court. However, the admissibility of these statements may be challenged if the driver was not properly advised of their Miranda rights, or if the statements were obtained through coercion, threats, or promises. A defense lawyer can challenge the admissibility of incriminating statements and argue that they should not be admitted as evidence in a DWI case.

A DWI charge can have serious consequences for a defendant, including fines, license suspension, and even jail time. However, by working with an experienced defense lawyer, it may be possible to challenge the admissibility of evidence and improve the chances of obtaining a favorable outcome in the case. If you have been charged with DWI, it is important to seek the advice of a knowledgeable defense attorney as soon as possible.

At Mary Beth Harrell Criminal Defense and DWI Lawyers, we understand the severity of DWI charges, and our DWI attorneys in Killeen and Copperas Cove possess the necessary skills and resources to mount a strong defense on your behalf. Our objective is to get the DWI charge dismissed, seek a plea reduction to a lesser offense, or obtain an acquittal in court. We have extensive experience questioning police officers and examining the evidence to build a solid defense strategy.

If you have been arrested for DWI, it is crucial to have a skilled criminal defense attorney by your side. To schedule a consultation and learn more about your rights and legal options, please call us or complete our contact form. Our legal team represents clients in Killeen, Copperas Cove, Temple, Belton, Waco, and other areas of Coryell, McLennan, and Bell Counties.