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Warrantless Blood & Urine Tests in Texas

In an effort to make it easier for Galveston-area prosecutors to prove DWI cases, Texas has an “implied consent” law with respect to blood tests. This means that if a police officer has probable cause to arrest a motorist on suspicion of drunk driving, the motorist is legally required to submit a blood sample for analysis in order to “determine the alcohol concentration or the presence in the person’s body of a controlled substance.” The motorist may also consent to other tests, such as a urine analysis.

The “implied consent” means that if the motorist refuses the blood test, said refusal can be used against them in court. The arresting officer will also confiscate the motorist’s driver’s license, which can be suspended up to 180 days even if the individual is never criminally charged with DUI. The motorist may challenge this suspension in an administrative hearing, but the burden is on the accused to prove the arresting officer lacked “reasonable grounds” to demand the blood test.

Are Implied Consent Laws Constitutional?

The Fourth Amendment to the U.S. Constitution guarantees all citizens the right to be free from “unreasonable searches.” Normally, this means that police may not conduct any type of search–such as a blood or urine test–without first obtaining a warrant from a judge. So how do “implied consent” laws like the one in Texas square with the Fourth Amendment’s warrant requirements?

The U.S. Supreme Court recently considered this question. In a series of cases decided this past June, the Court held that warrantless blood tests were, in fact, unconstitutional. The Court specifically said a North Dakota could not face criminal liability–i.e., the possibility of fines or imprisonment–for refusing to take a blood test. But the Court went on to say that police could require a DUI suspect to take a breath test, as that was less “invasive” than a blood or urine test.

In the wake of the Supreme Court’s decision, Minnesota’s Supreme Court held in October that a driver could not be criminally prosecuted under that state’s implied consent law for refusing to take a warrantless blood test.

But it is important to note the U.S. and Minnesota Supreme Court decisions only dealt with a driver’s potential criminal liability. It did not address potential civil or administrative penalties, such as the automatic driver’s license suspension mandated by the Texas implied consent law. Nor did the U.S. Supreme Court decision specifically address warrantless urine tests. The Minnesota Supreme Court decided that urine tests should be treated the same as blood tests, but other states may reach a different conclusion unless and until the U.S. Supreme Court clarifies its position.

Ultimately, the law in this area continues to evolve. That is why if you are accused of a DWI or facing potential sanctions for refusing a blood or urine test, it is important that you speak with an experienced Houston DWI attorney. Contact the Law Offices of Tad Nelson & Associates if you require immediate assistance from a League City DWI lawyer.