What Evidence Is Used in a DUI Case? The government has the duty to prove any driving under the influence charges against you beyond a reasonable doubt. You are not required to say anything. The prosecution must present evidence to show that you committed each element of a Tennessee DUI charge. In most DUI cases, the police officer who stopped you, observed you, and asked you to submit to any tests will testify against you. The officer will discuss what tests were taken and the results of those tests, as well as introduce your refusal to submit to any tests.

If the test results do not support their claim, the officer can introduce other evidence of your intoxication; although without the proper test results or evidence of a refusal, it is more likely the judge a jury will acquit you.

What are the key elements of a Sevierville DUI charge?

Tennessee law requires that the prosecution show, through evidence and testimony, the following:

  • You drove or were in physical control of a motor vehicle.
  • The vehicle was driven on public roads or highways in Tennessee or any “streets or alleys, or while on the premises of any shopping center, trailer park, or apartment house complex, or any other premises that is generally frequented by the public at large.”

The prosecutor must also show one of the following:

  • You were “[u]nder the influence of any intoxicant, marijuana, controlled substance, controlled substance analogue, drug, substance affecting the central nervous system, or combination thereof” and your ability to safely operate the vehicle was impaired to the point that you were deprived for the clear mind and control or yourself that a driver would normally possess.
  • Your blood alcohol content (BAC) level, measured by a breath or blood test, was .08 or higher.
  • Your BAC was .04 or higher and you were a commercial motor vehicle driver.

How does the prosecution prove these elements?

Before an officer can order a driver to pull over to the side of the road or to a safe location away from traffic, the officer must have good reasons to believe you were the person driving the vehicle on a type of road covered by the statute. Generally, the officer must also be able to show that there were reasonable grounds to believe you were driving while impaired or committed some other traffic infraction.

Normally, the evidence presented to support this part of the DUI case is the testimony of the police officer that he/she saw you driving a car, the type of car you were driving, where you were driving, and why the officer believed that he/she had reasonable suspicion to stop you.

To support the claim that you were intoxicated, the officer will normally testify that he/she saw you committing a traffic violation, observed you swerving in and out of lanes, or describe some type of erratic movements. An officer cannot randomly direct any driver off the road unless there is an approved checkpoint procedure.

If the officer is called to the scene of an accident, he/she will need to add additional testimony to support the claim that you were the driver of the vehicle (and not someone else in the car) and that the location of the vehicles at the accident site indicates you were driving on a public road or a frequently traveled private road. Generally you can find this information in the police report. (If you dispute the location of where you were pulled over in the report, talk to us.)

How does the prosecution determine whether you were intoxicated?

The evidence of intoxication includes the following:

  • Physical observations. Typically, the officer will observe you first to see if there are indicia of intoxication. These observations often include slurred speech, bloodshot eyes, an alcoholic breath odor, poor balance, and other physical indicators.
  • Field sobriety tests. The officer will then likely ask you to submit to field sobriety tests. There are standard tests that are used such as asking you to walk and turn, to stand on one leg, and to follow an item the officer is holding with your eyes (known as the horizontal gaze nystagmus test). The officer has a duty to explain what you are supposed to do.
  • Chemical tests. Drivers are required in Tennessee to submit to breath and blood tests if requested by a police officer who suspects drunk driving or else face losing driving privileges. The most common test is a beath test that is given at a local police station. The officer can also obtain a warrant to collect blood at the local hospital.
  • A refusal to take a test. Drivers in Sevierville and across the state give their implied consent at the time they obtain their driver’s license to submit to chemical tests based on a police officer’s suspicion of driver intoxication. While you do have the right to refuse the test, the refusal to take the test (provided the officer explained the consequences) can be introduced as evidence at a DUI trial.
  • Any statements. It is always best not to say anything if you are arrested for a DUI. The officer does have a duty to explain that you have the right to be silent and to talk to a lawyer. Any statements may be used as evidence against you.
  • Observations of alcohol containers. If the officer sees beer cans or liquor bottles in your vehicle or on your person, the officer can testify about these observations.
  • The testimony of eyewitnesses. Anyone who observed you drive or observed you after an accident can testify as to your possible impairment level.
  • Video evidence. Most officers are equipped with body cameras or cruiser video. If the prosecutor has video of you driving or what happened immediately before or after an accident, that evidence, if properly authenticated, may be introduced in court.

Our defense lawyers challenge whether evidence against you, such as breath test results, is admissible. We contest the validity of the evidence and the credibility of the police officer. At Delius & McKenzie, PLLC, our DUI defense lawyers are skilled at filing motions to suppress evidence, cross-examining the police and other witnesses, and negotiating with the prosecution. We’ll assert every possible defense to the DUI charge that applies to your case. To discuss your rights with an experienced criminal defense lawyer, call us or complete our contact form to arrange a free consultation. We represent defendants in Sevierville, Seymour, Gatlinburg, Pigeon Forge, and the surrounding areas.