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When Can Police Take Blood Samples After a Possible DWI Accident?

Updated: Feb 11, 2023 @ 11:06 pm

Less than 1 minute Reading Time: Minutes

If you are involved in a suspected DWI accident, the police will make every effort to take a blood sample from you for testing purposes. Even if you refuse to consent to such a test, a police officer can obtain a warrant from a magistrate if there is probable cause to suspect you were intoxicated at the time of the accident.

But what if an officer demands a test before getting a warrant?

Does that have any relevance to your case if another test is taken after the warrant is issued?

Court: No Need to Inform Magistrate of Prior Warrantless Blood Test

A recent case from here in Houston, Islas v. State, addressed just such a situation. The defendant was driving around 1 a.m. on New Year’s Day of 2014 when he ran a red light and collided with another vehicle. A passenger in the other vehicle was thrown from the car. A bystander attempted to perform CPR of the injured passenger, but he died as a result of his injuries.

HPD Officer Suspects Intoxication

A Houston Police Department officer at the scene “came into contact” with the defendant, according to court records. The officer observed the defendant’s breath smelled of alcohol. At that point, the officer requested assistance from an HPD drug recognition unit. A second officer from this unit met the defendant at the hospital.

Second Officer Conducts Field Sobriety Tests

At 2:40 a.m.–about 1 hour and 40 minutes after the accident–hospital staff took a sample of the defendant’s blood for purely medical purposes. The second officer also observed the defendant’s breath smelled of alcohol and that he had “slurred speech” and “cyclic mood swings.” The second officer then administered a series of field sobriety tests, which indicated the defendant was intoxicated. At 2:59 p.m., the second officer instructed hospital staff to take a second blood sample. The defendant did not consent to this action, and the second officer had not yet obtained a warrant.

Third Blood Test Leads to Intoxication Manslaughter Charge

However, the second officer did file a search warrant request. A magistrate signed the warrant at just after 4 a.m., and the hospital staff took a third and final blood test of the defendant at 5:24 p.m. Based on analysis of the results of this third test, law enforcement determined the defendant’s blood-alcohol content at 1 a.m.–the time of the accident–was between 0.08 and 0.14, which exceeded the legal limit.

Defendant Pleads Guilty, Appeals Warrant Affidavit

Based on this evidence, prosecutors charged the defendant with intoxication manslaughter. The defendant pleaded guilty, reserving his right to appeal the legality of the third blood test. Before the Texas 14th District Court of Appeals, the defendant argued that the second officer failed to mention in his affidavit to the magistrate that he instructed the hospital to take the second blood test without a warrant. The defendant maintained the affidavit was “misleading” and therefore unconstitutional under binding U.S. Supreme Court precedent.

14th District Upholds Warrant

The 14th District disagreed. It held the Supreme Court’s decision only invalidates a warrant “if there is an affirmative misrepresentation in the warrant affidavit” that is “material and necessary to establishing probable cause.” That was not the case here. The second officer alleged sufficient probable cause. And the appeals court noted there was no case law supporting the defendant’s view that “an affidavit in support of a warrant for a subsequent blood sample must inform the magistrate of the prior blood draw.”

Need Help With A Similar Criminal Case?

Contact a Intoxication Manslaughter Lawyer Today

Following a possible DWI accident, law enforcement will employ every legal tactic it can to build a case against you. Your best option is to contact a qualified Houston DWI accident attorney as soon as possible. Call the Law Offices of Tad Nelson & Associates in League City or Galveston today if you need immediate assistance.

Houston DWI Lawyer Tad A Nelson is Board Certified in Criminal Law by the TBLS.

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