How Do You Challenge a DWI Blood Test?

If you have ever been accused of driving while under the influence, then you are familiar with a blood test. Compared to a breath test or a field sobriety test, a blood test is one of the most accurate tests that you can take to identify your sobriety. Or is it?

While a blood test is an accurate analysis of sobriety, there are actions that medical professionals take that can affect the results of the test. If you have been charged with a felony DWI offense, you need an experienced Killeen criminal defense attorney on your side who can challenge the charge on your behalf.

How are blood tests conducted?

When you have been arrested for a DWI, you will be asked to participate in a blood test. It is important to know that a police officer must have reasonable cause to believe that you were under the influence while driving. They cannot just demand that you participate in a blood test. They must obtain a warrant before a blood test can even be administered. The police officer also has a legal duty to inform you of your right to decline submitting a sample for blood testing, as well as the penalties that you can face for failing to submit a sample, which can include losing your driving privileges.

When having a sample of blood taken for testing, a licensed nurse or physician is the only medical professional allowed to handle the procedure. Because licensed medical professionals are the only parties allowed to perform these tests, blood tests cannot be conducted at the scene of the alleged DWI incident.

Are blood tests credible?

After submitting a sample of your blood for a blood test, you may think that the results are valid and bulletproof . However, that is not always the case. There are many factors that can affect your blood test sample. Like everyone else, medical professionals are capable of making mistakes. Unfortunately, these mistakes can cause you to face serious legal consequences if you have been charged with a DWI offense. The results of your blood test are only as credible as the process that the medical professional followed while obtaining your sample.

Can DWI blood tests be challenged in Texas?

Because there are many opportunities for a blood sample to become tainted, blood tests can definitely be challenged in court. Your criminal defense lawyer can request that your blood sample be withdrawn as evidence if the sample can be discredited. When it comes to challenging the credibility of a blood sample, lawyers typically use two methods. The first is demonstrating that the blood sample was improperly obtained or managed, and the second method is arguing that the blood sample was obtained through an illegal search and seizure.

Improper procedures

When collecting blood samples, it is very important for medical professionals to properly handle and maintain the sample. It is very easy for the blood sample to become easily contaminated. For example, a licensed physician may contaminate a blood sample after allowing it to ferment in a vial. Fermentation is a scientific process that can cause alcohol content to increase in a blood sample. That means that the actual blood alcohol content (BAC) level found within your blood sample could have been tampered with due to a medical professional’s mistake.

Another example of an improper procedure is a break in the chain of custody when it comes to handling your blood sample. The medical professional who took your blood sample is not the only person responsible for properly maintaining it. Although police officers are not allowed to collect a blood sample from you, they are responsible for documenting its whereabouts.

That means that all people who come in contact with your blood sample must be accurately documented and handle it as delicately as possible. When there has been a break in the chain of custody or a moment where your blood sample was not properly accounted for, your criminal defense lawyer can argue that the evidence must be dismissed.

Illegal searches and seizures

Another common argument that your criminal defense lawyer can make to have your blood sample dismissed is that it was obtained through an illegal search and seizure. Before a blood test can even be conducted, the police officer must obtain a search warrant. A police officer also cannot conduct a blood test if the defendant is incoherent or unconscious. If the defendant is not conscious enough to refuse or agree to a blood test, the police officer does not have the right to draw their blood (except under certain conditions) Obtaining a blood sample without consent is an example of an illegal search and seizure, and can result in the blood sample being thrown out.

How a Killeen DWI defense lawyer can help

When you have been charged with a DWI, you may face serious legal consequences for years to come. However, even though you have been accused of a DWI, nothing is set in stone. You still have a chance to challenge the DWI offense and fight for your legal rights. To give yourself a greater chance of having your charge reduced or eliminated altogether, you need the help of a criminal defense lawyer.

A criminal defense lawyer can investigate how your blood sample was collected and the likelihood that your blood sample was contaminated throughout the chain of custody. Your criminal defense lawyer can also determine whether all proper procedures were followed to collect your blood sample and, if not, request that it be withdrawn as evidence in your trial.

You do not have to accept a DWI conviction and the penalties that come with it. You need a lawyer who will work hard to protect your rights, from the time that you are arrested through the resolution of your case. Contact a smart and strategic DWI defense attorney at Mary Beth Harrell Criminal Defense and DWI Lawyers. We represent clients in Killeen, Copperas Cove, Temple, and Belmont. Call us today at 254-680-4655, or fill out our contact form to schedule a case evaluation today.