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When Police, Hospitals Disagree on Search ConsentTexas has an implied consent law that states that a licensed driver has consented to chemical testing if a police officer has probable cause to believe that they have been driving while intoxicated. The law applies even when the suspect is unconscious and unable to give consent. When a DWI suspect is injured in an incident, the officer will often collect a blood sample from the suspect at the hospital, where there is a trained staff available to draw the sample. However, some hospitals have a policy against drawing blood from a patient who is unable to consent. This can lead to disputes between police officers trying to obtain evidence and hospital staff concerned about the patient’s privacy.

Recent Example

A nurse at a Dallas area hospital recently refused to allow police to draw blood from a DWI suspect until they presented a warrant. The male suspect had been involved in a car accident that killed two women. The man had been convicted for DWI five times previously, gotten off of probation five days earlier, and just had the ignition interlock device removed from his vehicle. A breath test showed no traces of alcohol, but the officer believed that he was intoxicated because they claim that he:

  • Had been driving the wrong way at the time of the accident;
  • Said he had been taking Xanax;
  • Had bloodshot eyes; and
  • Spoke rapidly.

Police arrested the man, who allegedly agreed to a blood test. After the suspect was taken to a hospital, a nurse told the officer that they could not do a legal blood draw on the suspect, claiming that the suspect could not consent to the test because he was intoxicated. The officer obtained a warrant to draw the blood sample from the suspect, who has been charged with two counts of intoxication manslaughter.

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Court Strikes Down Exigency Claim, Warrantless Blood TestThe Texas Court of Criminal Appeals recently upheld a trial court’s decision to bar a blood sample from being used in a high-profile driving while intoxicated case. In The State of Texas v. Joel Garcia, the defendant has been charged with three counts of intoxication manslaughter for allegedly being under the influence of alcohol and cocaine during a fatal traffic accident. The trial court judge approved the defendant’s request to suppress the test results from a blood sample that police obtained without a warrant. The Texas Eighth District Court of Appeals overturned that ruling, stating that exigent circumstances permitted police to forgo the warrant. The Court of Criminal Appeals, the state’s highest criminal appeals court, reinstated the trial court’s ruling.


The Fourth Amendment to the U.S. Constitution requires law enforcement to present a suspect with a warrant before conducting a search, which includes the drawing of blood to test for intoxication. Courts may allow prosecutors to present evidence that was obtained without a search warrant if there was an immediate danger of losing the evidence if law enforcement had waited for the warrant to be issued. In The State of Texas v. Joel Garcia, prosecutors claimed three exigent circumstances that necessitated drawing the blood immediately:

  • The chaotic nature of the accident scene delayed the investigation and may have allowed intoxication levels in the defendant's blood to naturally dissipate;
  • The presence of cocaine in the defendant's system could have dissipated at an unpredictable rate; and
  • The hospital was planning on administering an IV on the defendant, which may have diluted the blood sample.

Court Reasoning

In rejecting the exigency claims, the Court of Criminal Appeals stated that proof of exigency must come from historical facts and what police could reasonably infer. The court soundly rejected the first two claims. Not enough time had passed for the police to believe that the defendant's blood alcohol concentration would substantially drop if they waited for a warrant to be approved. Police did not cite a suspicion of cocaine use leading up to drawing the blood sample. As for the third claim, the court stated that police had no reason to believe that medical treatment was imminent because:

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Mistakes Can Occur During DWI Blood Test ProcessThough more accurate than a breath test, a blood test can still have inaccurate results in a driving while intoxicated case. There are many chances for a blood sample to become contaminated during the process, resulting in the sample showing a higher blood alcohol concentration level than was actually in the driver’s blood at the time of the arrest. An experienced DWI defense attorney knows where errors are likely to occur in the blood test process that may make the test results inaccurate and inadmissible in court.

Blood Drawing

Mistakes in taking the suspect’s blood can contaminate the sample from the start. A police officer drawing your blood is not always as skilled as a medical professional. The officer may make a mistake by:

  • Waiting too long to draw the blood sample;
  • Contaminating the sample with the alcohol swab used to clean the extraction site on the skin; or
  • Drawing a blood clot, which has a higher concentration of blood alcohol than a normal blood sample.

You may need to recount possible mistakes made during the blood drawing process, as the person drawing the blood is not required to testify.

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New Program May Expedite Blood Search Warrants During DWI ArrestsIf you have been charged with driving while intoxicated, you can refuse to submit to a blood alcohol test. In Texas, police officers can request a blood search warrant that requires a sample of your blood to be drawn and tested for alcohol or other intoxicating substances. Executing the warrant can take hours because the officer often needs to go to the station or court house to obtain it. However, some Texas municipalities are testing a mobile communications program that enables officers to receive an approved blood search warrant in the field. If the program is successful, it may become easier for law enforcement to obtain evidence against DWI suspects.

Blood Search Warrant

Under Texas law, a judge can issue a blood search warrant that allows a medical professional to collect a DWI suspect’s blood sample as possible evidence of intoxication. An officer can request a blood search warrant as long as:

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Bexar County

In the historic King William District

1011 S. Alamo,
San Antonio, Texas 78210
888-726-5625 Toll Free


Guadalupe County

109 Court Street,
Seguin, Texas 78155
888-726-5625 Toll Free