DWI Notes for Tennessee (TN)

Driving while intoxicated known as DWI, DUI (driving under the influence) or OUI (operating under the influence) is a serious offense in Tennesse. Losing your license to operate a vehicle in TN is just one of the penalties. It is in your best interest to hire an experienced criminal defense attorney to handle your case. A lawyer who specializes in drunken driving cases will be able to defend your constitutional rights. The field sobriety tests, the breathalyzer or Alcotest blood alcohol content (BAC) readings may be flawed and could result in a not guilty verdict in court. Only an experienced DWI lawyer will know how these tests should be administered and whether they were performed according to the guidelines provided by the National Highway Traffic Safety Administration (NHTSA).

Standardized Field Sobriety Testing

The National Highway Traffic Safety Administration has created a set of Standardized Field Sobriety Test (SFST). These three tests have to be administered and evaluated in a standardized manner to obtain accurate indicators of impairment. Most police officers fail to administer these tests correctly. Your DWI attorney may be able to challenge the validity of the stop and arrest by reading the report submitted by the police officer or trooper or by the testimony provided in court.

The Standardized Field Sobriety Tests were developed from research sponsored by the National Highway Traffic Safety Administration (NHTSA). NHTSA then developed a training regimen for law enforcement officers to provide a consistent way of evaluating the results from DWI suspects. Although police officers use a variety of tests when they pull someone over for suspected driving under the influence of alcohol, the three that are NHTSA accepted are:

• Horizontal Gaze Nystagmus
• Walk and Turn
• One Leg Stand

Other tests, like counting backwards or saying the alphabet from one letter to another have not been proven to be reliable indicators of being intoxicated or under the influence. Keep in mind that even the reliable tests must be administered correctly for them to be valid indicators of DWI.
Horizontal Gaze Nystagmus (HGN) Testing

The horizontal gaze nystagmus test checks if you have involuntary twitching of the eyeball. This occurs naturally as the eyes gaze at a right angle towards the side. When someone is under the influence of alcohol, nystagmus (twitching of the eyeballs) occurs at lesser angles. During this test, the officer will have the subject follow a pen or light with his eyes. The officer must observe the subject eyes. The three indicators that the officer looks for in each eye are:

• If the subject is smoothly following of the moving object with his/her eyes
• If the eye begins to jerk distinctly at the maximum range (right angle)
• If the angle of jerking begins within 45 degrees of center

According to the National Highway Traffic Safety Administration has determined that if between both eyes, four or more indicators are present the subject is probably under the influence. This test is therefore allowed for the purpose of making a DWI/DUI arrest and requiring a breath test at the police station.

Walk & Turn and One Leg Stand Tests

The other two tests that the National Highway Traffic Safety Administration believes are accurate predictors of DWI are the so called, “divided attention” tests. These tests can supposedly be done by most sober people. Although many police officers will tell you that they hear people say, “I can’t do that when I’m sober.” (By the way, this is not the wisest thing to say if you are a DWI suspect.) According to NHTSA, suspects cannot usually follow instructions and perform physical tests when they are impaired.

Walk & Turn

In the Walk & Turn test, the police officer will ask the DWI suspect to take nine steps placing the heel to the toe in a straight line. Someone suspected of DWI should follow instructions carefully for this test. The seven indicators of failure in the walk and turn are:

• Failure to maintain balance while listening to instructions
• Starting before the instructions are completely stated
• Stopping while walking to regain balance
• Lack of heel to toe touching
• Using arms to regain or maintain balance
• Loss of balance while turning
• Taking an incorrect number of steps

NHTSA research indicates that the majority of DUI suspects who fail two or more of the above items are operating under the influence. You will be arrested and charged with DUI/DWI and required to provide a breath sample.

One Leg Stand

The one leg stand test requires the DWI suspect to stand with one foot approximately six inches off the ground and count aloud starting with one thousand and increasing by one (one thousand-one, one thousand-two, one thousand three, etc…) until told to lower the foot by the police officer. The officer is required to time the subject for 30 seconds. The four indicators of DWI impairment are:

• Swaying while balancing
• Using arms to balance
• Hopping to maintain balance
• Placing the foot down

NHTSA research indicates that the majority of DWI suspects who exhibit two or more of these indicators are under the influence.

Probable Cause

The field tests that are administered on the side of the road are used by police officers to establish probable cause for the arrest. Your DWI attorney may be able to challenge these tests as well as the reason you were stopped in the first place. In order for these tests to yield valid results they have to be administered in the proscribed manner and must be evaluated based on a total number of indicators. The more indicators are present, the more likely that the person is operating under the influence.

Because most people charged with DWI do not understand what these tests are looking for or how they should be administered, it is extremely important that a lawyer that specializes in DWI defense be used to examine all the evidence and provide a recommendation on how to proceed.

Designed and Hosted by Alonso Consulting, Inc.