## Facts

- One evening, Ronald Lynn Cox drove his van erratically on a highway at a high speed and crashed.
- Eyewitnesses stopped to help Cox out of the van and later described him as dazed but coherent, reporting he could answer questions.
- Police responded to the scene, found alcohol in Cox’s vehicle, and noticed the odor of alcohol on Cox’s breath.
- Officers administered a breath test, which Cox failed.
- Cox admitted he drank one bottle of alcoholic “lemonade” before driving.
- Cox was arrested and taken to the police station, where he was questioned; the questioning was recorded on video.
- The State charged Cox with driving under the influence (DUI), and Cox went to trial.
- At trial, Cox claimed he had a history of sleepwalking and sleep disorders and contended he was asleep at the time of the crash and for several hours afterward, including during the police-station questioning.
- Cox’s treating physician for chronic sleep apnea testified that Cox had reported prior sleepwalking episodes, including cooking and eating while asleep.
- The physician also testified a sleepwalking person might answer questions but would tend to respond in a simplistic way and might not make sense.
- After the State showed the physician the station-house video, the physician testified Cox did not appear to be asleep because his demeanor and ability to answer more sophisticated questions were inconsistent with sleepwalking.
- The jury convicted Cox. He appealed, arguing the conviction could not stand because the State did not prove he drank alcohol voluntarily.

## Issues

1. In a Texas DUI prosecution, must the State prove that the defendant voluntarily consumed alcohol to establish criminal liability for intoxicated driving?
2. Was the evidence sufficient for the jury to find Cox’s conduct was voluntary and to reject his claim that sleepwalking rendered his driving (and related conduct) involuntary?

## Decision

- The Texas Court of Appeals affirmed Cox’s DUI conviction.
- The court rejected Cox’s argument that the conviction failed because the State did not prove he voluntarily drank alcohol.
- The court held the record allowed a rational jury to reject Cox’s sleepwalking theory and find the voluntary-act requirement satisfied.

## Legal Principles

- Texas criminal liability generally requires a voluntary act; truly unconscious or involuntary conduct may defeat liability when voluntariness is lacking.
- For intoxicated-driving offenses, the State must prove the statutory elements (including operation of a motor vehicle in a public place while intoxicated) and may prove disputed elements through circumstantial evidence.
- A defendant may present evidence that a sleep disorder or sleepwalking explains the conduct and negates voluntariness, but the factfinder decides what weight to give that claim.
- Video evidence and witness observations bearing on a defendant’s awareness and responsiveness may support a finding that the defendant was not asleep and was acting voluntarily.
- On legal-sufficiency review, the appellate court views the evidence in the light most favorable to the verdict and asks whether any rational juror could find the elements beyond a reasonable doubt, leaving credibility choices to the jury.

## Conclusion

The court affirmed Cox’s DUI conviction because the jury could reasonably rely on eyewitness accounts of Cox’s coherence, the presence and odor of alcohol, the failed breath test, Cox’s admission that he drank alcoholic lemonade before driving, and the doctor’s video-based testimony that Cox did not appear to be sleepwalking, to find that Cox acted voluntarily and was intoxicated while operating the vehicle.


Cox v. State, 2013 WL 4528675 (2013)