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  • Writer's pictureJustin Sparks

What Is a Chemical Test for DUI Offences? Deep Dive and Why You May Need a DUI Defense Attorney

A DWI in Texas constitutes a misdemeanor offense. However, before any charges can be levied against you, intoxication must be proven. This may take the form of a urine, breath, or blood test. The idea is to measure blood alcohol concentration (BAC) and where it compares to the legal limit of 0.08%.

Additionally, the arresting officer may observe the loss of typical use mental or physical faculties. While the chemical test options are heavily relied upon, they are not necessarily always accurate. What makes it worse is that the implied consent laws in Texas create a big problem for those implicated in refusing a chemical test.

Nevertheless, you may be able to avoid strong penalties with an experienced DUI defense lawyer in your corner.

Refusing Chemical Testing Under Texas Law

Refusing Chemical Testing Under Texas Law

Thanks to provisions outlined in the Texas Transportation Code 724.011, by driving in public in Texas, you have given implied consent to chemical testing. So, while there may be other states in which you can say no to the chemical tests, Texas happens not to be one of them.

Should you refuse to submit to chemical testing, you can face consequences that vary based on your history of test refusal. Here's a quick breakdown of what the penalties look like:

  • First time refusing a chemical test - 180 day license suspension period

  • Second or higher chemical test refusal within 10 years - two-year license suspension period

Note, however, that if refusal to submit to chemical testing nets you a driver's license suspension, you can apply for an occupation license, which allows you to drive for school, work, or household necessities.

Types of Chemical Tests

When pulled over in Texas for being suspected to be under the influence, the officer usually asks a few questions and then informs you that a test is about to be conducted. Again, the intention is to ascertain where a driver's blood alcohol concentration measures up to the 0.08% legal limit.

Below is a brief look at blood tests, breath tests, and urine tests.

Breath Test

A preliminary breath test or breathalyzer is potentially the most common chemical testing mechanism of the three. Breath tests are likely used so often because of the simplicity of doing them, which means test results are easily available.

You're made to blow into a breath-testing device to have your blood alcohol content measured. Note that the reported blood alcohol level here is known to not necessarily be as secure as a blood test.

It's important to make a distinction here. While refusing chemical tests overall can result in consequences you can refuse to submit to the breath test in particular. Note, however, that this tends to mean a blood test is on the table next.

While blood tests do require a warrant, getting one is incredibly easy, and once the law enforcement officer has one, collecting blood samples becomes legal for a chemical test. It is at this point that your refusal has consequences.

Urine Test

A urine test is also known as a urinalysis and is notorious for being the least reliable testing method of all the DUI chemical tests. Drugs, for example, remain in a person's system way longer than alcohol does.

So, what you may have is a situation where urine test results indicate the presence of drugs when the driver is no longer driving under the influence. The idea behind DWI chemical tests is to confirm drug-influenced or drunk driving that a driver is currently doing.

Blood Test

While blood testing requires a warrant as indicated before, it is the most accurate chemical test type of the three. Typically, about 100 ml of blood is enough for this kind of alcohol test. A process known as gas chromatography is used to get the chemical test results in this case and it indicates if you're driving under the influence or not.

A breath or blood test can be used against you in court, but the former is less difficult to fight. An aggressive defense can use the shortcomings of a breath test to your advantage. However, the accuracy of blood testing makes this more difficult.

Therefore, you're advised to submit to breath tests for the best possible outcome. To help you out, it is important to seek an attorney's help on how to prepare for a DUI court hearing.

Concerns Surrounding DUI Chemical Tests

Concerns Surrounding DUI Chemical Tests

Alcohol testing doesn't necessarily provide an accurate representation of the amount of alcohol in a driver's system. A case made by a DWI attorney in Fort Worth TX aims to use this fact in court to fight against your charges. Here are a few of the shortcomings of urine, breath, or blood testing that attorneys may focus on.

Machines Not Properly Maintained

Breath testing machines have a natural margin of error even when they are adequately maintained. When maintenance is not being carried out as it should be, a test subject can get a result that doesn't represent the real situation adequately.

Law enforcement sometimes doesn't do what is necessary to keep the machines in proper working order, which helps your defense when your attorney speaks to it.

Residual Alcohol

The amount of alcohol present in the lungs is meant to be used when a breath analysis is used to ascertain whether drunk driving is taking place or not. Doing this accurately means officers should allow suspects about a 10-minute reprieve to ensure no alcohol is in the mouth. Failing to do this can also result in a favorable outcome for you.

Blood Sample Preservation

A blood sample must be handled correctly. If not, fermentation can occur, which means a driver's BAC is going to be inflated. A competent lawyer serving your cause is going to ensure that mishandled samples following BAC tests are not used against you.

Retain an Experienced Ft. Worth, TX Attorney if You've Been Accused of a DUI

Whether you have prior alcohol-related offenses or not, you want to ensure that you have the best law firm in your corner to provide the legal help you need. Remember the parameters of your attorney-client relationship means sensitive or confidential information provided is never shared. Having an experienced lawyer will help you deal with any issues related to DWI charges, including how to get a DWI record expunged in Texas.

Schedule a free, no-obligation consultation in Fort Worth, TX, today by calling Sparks Law Firm at (817) 381-7846. This free evaluation helps you to understand your DUI case situation and what a plan of action may look like.


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