What Must the State Prove in a Tennessee DUI Case?

Driving under the influence (DUI) charges are among the most serious traffic offenses prosecuted in Tennessee. They are crimes, rather than simple moving violations. However, the fact that you have been accused of drunk driving does not mean that you’ll be convicted. The state needs to prove its case beyond a reasonable doubt, and there are many potential defenses that might be employed based on the evidence. 

Under Tennessee Code § 55-10-401 (2024), prosecutors generally need to prove two main elements to secure a conviction:

• The driver was in physical control of any motor vehicle (not necessarily a car or truck) while on a street or highway, or in an alleyway, in a parking lot or any other place regularly used by the public.
• They were under the influence of mind-altering drugs (legal or not) and/or alcohol that affected their ability to operate the vehicle safely.

It is essential to note that a motorist can be found guilty of DUI even if their vehicle was not in motion at the time the police stopped them. Merely being physically present behind the wheel, keys within reach, is enough to establish control over the vehicle and meet the first criterion of the charge.

The second element of the charge may be proven through chemical testing, typically a breath or blood test, that shows that a driver’s blood alcohol concentration (BAC) was .08 percent or higher (or .04 percent for those with a commercial driver’s license and just .02 percent for drivers under 21 years of age). This is known as per se or statutory intoxication, which means that no other evidence that a driver is impaired and unsafe to drive is necessary for a conviction. 

However, even if a driver’s BAC did not meet the legal intoxication level, they may still be convicted if other evidence shows that alcohol or drugs impaired their ability to drive safely. Evidence frequently used to show impairment includes video footage of their conduct in traffic, crash reports, videos of field sobriety test performance and the testimony from the arresting officer and other parties, such as drivers who crossed paths with the defendant.

These elements of a DUI case are often more complicated to prove than most people realize. Numerous defense strategies focus on proving that the prosecution failed to meet its burden when establishing these elements of a DUI case. A skilled DUI defense attorney may effectively challenge the accuracy of the chemical testing used, the veracity of the arresting officer’s observations, the reliability of field sobriety tests and even the legal basis for the traffic stop itself. 

The Collierville Law Firm provides aggressive representation to West Tennessee clients who are facing DUI charges. Schedule a free initial consultation by calling 901-614-0318 or contacting us online.