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Can a DWI Accident Be Caused by Substances Other Than Alcohol?

Updated: Jul 9, 2023 @ 2:49 pm

Less than 1 minute Reading Time: Minutes

When police suspect that drunk driving played a role in causing a traffic accident, they will quickly move to confirm their suspicions. Keep in mind, even if someone has not been consuming alcohol prior to an accident, they may be legally intoxicated by other means, such as through the use of prescription or illegal drugs. Although we often refer to DWI as “drunk driving,” in reality the prosecution does not need to prove that alcohol played any role in the defendant’s impairment.

Texas Man Convicted of DWI Due to Use of Depressant Drugs

Introduction to the case of Humphrey v. State

A recent unpublished decision from the Texas Second District Court of Appeals, Humphrey v. State, provides a helpful illustration. In this case, the defendant was driving his truck to work when he was involved in an accident. The police officer who attended the scene said the defendant was slurring his words and gave off a demeanor that suggested intoxication. The officer then administered several field sobriety tests with the defendant’s consent.

Presence of Hydrocodone and Etizolam in defendant’s system

After the tests suggested impairment, the officer placed the defendant under arrest. As it turned out, the defendant had not been drinking–a post-arrest breath test confirmed as much. But a subsequent blood test did reveal the presence of hydrocodone and etizolam in the defendant’s system.

Hydrocodone is a prescription opiate. The defendant lawfully possessed this drug. But etizolam can no longer be legally prescribed in the United States.

More to the point, a state medical expert testified at the defendant’s trial that etizolam functions much like Valium or Xanax in that it depressed the central nervous system and produced side effects “similar to those caused by alcohol.” In combination with the hydrocodone, another depressant, the expert said the side effects were multiplied.

A jury ultimately convicted the defendant of DWI.

Defendant’s argument on appeal

On appeal, he argued the trial judge improperly instructed the jury on the law. Specifically, the judge explained the prosecution had to prove the defendant was intoxicated, i.e., that he did not have the “normal use of mental or physical faculties by reason of the introduction of alcohol, a controlled substance, a drug, a dangerous drug, a combination of two or more of those substances, or any other substance into the body.”

The defendant argued the inclusion of the terms “alcohol,” “dangerous drug,” and “controlled substance” in the jury charge unfairly prejudiced him.

Court’s rejection of the defendant’s argument

The Second District rejected this argument and upheld the defendant’s conviction. The Court explained that under Texas law, the state “does not have to prove what substance a defendant consumed to become intoxicated.”

But when prosecutors argue the defendant was intoxicated by a substance “other than alcohol,” they do need to prove that substance “can cause intoxicating effects.” Here, the prosecution did so through the testimony of its medical expert.

Contact League City DWI Lawyer Tad Nelson Today

Even if you are taking a perfectly legal prescription drug, if you end up causing a car accident, prosecutors can still pursue criminal DWI charges against you. An experienced Galveston DWI defense lawyer can provide you with skilled advice and representation. Contact the Law Offices of Tad Nelson & Associates today if you need to speak with an attorney right away.

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

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