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  • Writer's pictureJustin Sparks

Can a DWI Blood Test Be Wrong? Get Legal Help from the Sparks Law Firm!

It's not uncommon for police officers around the country to catch young and old people drunk driving or even under the influence of illegal drugs. If those officers consider there are reasonable grounds to believe a driver is intoxicated, they may ask them to take a breath or blood test.

Drunk driving is a Class-B misdemeanor in Texas, so it's not something to take lightly. When people hear about DWI tests, they often think of the classic breathalyzer test police officers perform on the spot. However, a breath test is not as accurate as a blood one, so they may ask drivers to take it if they want a more reliable result.

However, what happens when blood tests aren't as accurate as people claim they are? Can blood tests make mistakes? This page has the answer to all those questions.

People facing a DWI driving offense can contact the Sparks Law firm to take care of the case and prove that the blood alcohol test clients went through was wrong.

What Is the Blood Alcohol Concentration Legal Limit in Texas?

What Is the Blood Alcohol Concentration Legal Limit in Texas?

Although drunk driving is a crime in Texas, it's not illegal for people to drive while having some alcohol in their bodies. Police officers ask people to take a blood test to know the blood alcohol concentration (BAC) they had while driving. The Sparks Law Firm can answer questions like, is a field sobriety test required in Texas?

The BAC limit in Texas is 0.8% alcohol concentration in the driver's blood, so it's not a problem if breath tests show a blood alcohol level lower than that.

Is a DWI the Same as a DUI?

Many people confuse DWIs and DUIs since they think they are the same. The short answer is no, but they can be the same depending on the case.

DUI stands for "Driving Under the Influence," which includes alcohol, prescribed drugs, or illegal drugs. DWI, on the other hand, means "Driving While Intoxicated." In Texas, drivers are intoxicated when they can't use their mental or physical faculties due to the presence of alcohol, controlled substances, prescribed drugs, or illegal drugs in their blood.

Understanding both terms shows that a driver could be under the influence but not intoxicated. Needless to say, intoxicated drivers will always be under the influence of a substance.

Does this change anything? The main change between both cases is that police officers asking a driver to take a DWI blood test need to also prove those drivers couldn't use their mental and physical faculties properly while driving in a public place.

Although this changes in different states, DWIs are way more severe in Texas than DUIs. As a matter of fact, DUIs are only charged to minors in this state. Apart from that, minors will face DUI charges regardless of how much blood alcohol content they have in their body since drinking is already illegal to them, even if they are not driving.

DUIs are more severe in other states than in Texas since DWI only includes alcohol and not drugs.

Can DWI Blood Tests Be Wrong?

Getting to the main part of this article, the truth is that although blood testing is one of the most effective -if not the most effective- ways to know if someone was driving under the influence, there are many scenarios in which a DWI or a DUI blood test can be wrong.

While it's not common to see it happen, it's something that can and has happened, so lawyers from the Sparks Law Firm know everything they need to do to prove that the blood testing process of its clients' tests altered its results and

It's worth noting people need a reason to question the veracity of a blood test since, regularly, there's nothing wrong with them. Most blood test dismissals happen when something in the storing, analyzing, or collecting process goes wrong.

Here are some of the most common reasons why blood testing can be wrong or at least questioned in Texas:

Issues When Collecting the Blood Sample

While it only takes a few seconds, collecting a blood sample is a delicate process that needs both the person taking the blood draw and the patient to be in a clean environment and use sterilized tools.

If a nurse, for example, uses a dirty needle or syringe for a DWI or a DUI blood test, its result changes. Aside from problems with the tools used for the medical procedure, it's proven that any issue while performing the blood draw process has a 50% of chances to show a false positive.

The problem with the people who take the blood test sample of anyone facing DWI charges is they aren't always medical professionals or someone with years of experience. This doesn't mean they will make mistakes but rather that they could make them.

Other problems in the blood draw, such as using the wrong tube, not taking enough blood, or hemolysis also change the results of a DWI or DUI blood test.

Lousy Analysis

Lab errors can also happen when analyzing a blood sample, which can help lawyers question the test. This includes things such as mislabeling, intermingling, or interchanging vials.

Although there are no excuses for it, labs in charge of delivering DWI or DUI blood test results handle a lot of paperwork, and it's not difficult to make mistakes when dealing with that much information.

Blood test results may not be accurate if nurses wait too long to draw blood samples, if someone contaminates them, or if they draw a clot.

Negligent Reporting

Almost all biological tests have an error margin people need to take into account before deeming a test reliable. Even flawless blood alcohol test results have a 0.02% error rate, and tests with an error margin of 0.08 or 0.10% can be used as evidence if a judge allows it.

Labs can't emit the results of a blood test until they know its error rate. However, negligent people in laboratories often do it, which is an opportunity for lawyers to question their results.

Contamination While Storing the Blood Sample

One of the main causes of the dismissal of a blood test is improper storage of the sample drawn from the defendant. Even temperature changes can cause fermentation and change the blood alcohol results.

Blood samples shouldn't be stored at room temperature for more than eight hours after the drawing process. If people at the lab place the sample in cold storage, it can last up to seven days. Hence, blood tested without following those deadlines won't be as accurate as it needs to be to work as evidence.

Can a Police Officer Force a Driver to Get BAC Tests?

If a police officer has reason to believe someone is under the influence of alcohol or any other psychotropic substance, they are more likely to perform a breath test instead of a blood one. However, since a breath test is not as accurate as the latter, police officers may ask the victim to get the latter in dangerous or more complex cases.

It's worth noting that arresting officers can only ask someone to get a blood test, but they can't take anything but breath samples unless the driver agrees to go to a lab. Thus, BAC test results that come from a person who didn't consent to get a blood test will always be dismissed.

Regardless of that, if the police officer asking for a blood draw is sure the other person was driving under the influence, they may look for a warrant to force the driver to take the test.

What's the Penalty for Drunk Driving in Texas?

What's the Penalty for Drunk Driving in Texas?

If it's proven that a driver was, beyond any reasonable doubt, driving while intoxicated for the first time, they will go to jail for three to 180 days with a $2,000 fine. Apart from that, the judge may take the defendant's driver's license for a year.

According to DWI law, penalties will worsen as people commit the same misdemeanors. If the person from the last example is caught drunk driving a second time, jail time will range from one month to one year with a $4,000 fine. This time, the driver will lose their license for two years.

Getting to the case where the driver does the same a third time, they can even go to jail for five years or more. While the two-year-without-license penalty stays the same, the fine would be now $10,000.

Conclusion - Where to Hire an Experienced DWI Attorney

The best way to avoid facing a DWI conviction or a DUI arrest is to never drive intoxicated or under the influence of any substance. However, if a police officer runs a breath or blood test on someone who was completely sober while driving and gets a false positive, that person should look for an experienced DWI attorney as soon as they can!

Hiring a lawyer from a DWI law firm like the Sparks Law Firm is the best thing defendants in Texas can do. These lawyers know everything about how drawing blood, storing it, or analyzing it incorrectly could lead to a mistake, so they will do everything in their hands to prove the blood test results of their clients were just false positives.


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