You have rights under the United States and Texas Constitutions against unreasonable search and seizure as it relates to traffic stops. For example, it is not permissible for a Texas law enforcement officer to pull you over simply because he or she “thinks” or “suspects” you may have been drinking. Officers often pull people over after they have left a bar, even when they have not actually seen any crime being committed.
Officers are required to have a reason to pull you over, such as a traffic violation. Officers often claim they saw violations such as:
If the traffic stop can be shown to have been inappropriately begun in violation of your constitutional rights, all evidence that was collected as a result of that illegal traffic stop can be kept out of court. This could result in dismissal of the charges against you.
Other types of constitutional violation defenses exist to help protect your rights against unwarranted or illegal charges of DUI/DWI. This especially applies to unconstitutional searches or seizures of your car, your person, or other aspects of the traffic stop. Constitutional violations can result in making the evidence collected as a result of the illegal search inadmissible, meaning the prosecutor cannot use it against you.
Another common constitutional violation occurs when law enforcement officer fails to properly follow the law regarding sobriety checkpoints. These checkpoints are designed to catch intoxicated drivers on the road by screening each passerby that goes through the checkpoint. However, law enforcement is expected to ensure that the checkpoint meets all of the constitutional requirements, otherwise any evidence collected is inadmissible. An experienced lawyer knows how to analyze your unique situation for constitutional violations that can be used as a defense in your case.
These so-called “tests” rely on the officer’s interpretations of the result of the test, which can be inaccurate, to say the least. These “tests” are also susceptible to false positives when a person has a physical or mental condition that may interfere with the testing, such as:
The results of a field sobriety test can be challenged in various ways to show that the officer was inaccurate in his or her observations.
In order to order a blood draw, police are required to have either your consent or a valid warrant. A person’s blood is subject to a higher level of privacy interest under the 4th Amendment to the U.S. constitution, therefore a violation of those requirements will result in the inadmissibility of the blood results.
Most challenges to a blood draw in a DWI case involve challenges to the way the sample was taken or challenges to the validity of the sample itself. The following are some of the most common reasons a blood draw is challenged.
If any of these or other defects exist, you can challenge the results of the blood draw and effectively defend yourself against this evidence.
Breath tests all too often create false-positive indicators of intoxication. A breath test can detect the presence of alcohol when you have not been drinking, such as when:
You can also challenge the accuracy of breath test results due to other issues with the testing or your particular body situation. For example, a person with a high body temperature (i.e., from a fever) will have a higher diffusion of alcohol into your lungs. If you had a fever at the time of your arrest, it can cast doubt on the breath test.
Other health conditions can also impact the breathalyzer test, such as having COPD. Those with COPD may not be able to produce an accurate breath sample. Those who are diabetic naturally produce acetone in their breath, which can incorrectly read as alcohol on a breath test.
All breath tests, both portable and those at the station, are expected to be properly calibrated and routinely checked for accuracy. This must be done by a person who possesses the proper licensing qualifications to perform these checks. The prosecution is required to provide this information to the defense. Any issues with the improper calibration of the test can result in the inadmissibility of it.
The same is true if the test is not administered according to the strict protocol put in place. Breath tests must be performed after a 15 minute waiting period or the results can be inaccurate. If performed incorrectly, the breath test can be deemed inadmissible as evidence against you.