What to Expect if Stopped for a DUI in Tennessee
Unless you’re a police officer or an attorney who specializes in DUI cases, you probably don’t know that DUI traffic stops involve multiple phases before an arrest for Driving Under the Influence is made. DUI detection typically involves three separate phases: Vehicle in Motion, Personal Contact, and Pre-Arrest Screening. It is important to note that the DUI detection process will not always include all three phases.
Phase One: Vehicle in Motion
Usually, the first phase of a traffic stop for suspected DUI is the Vehicle in Motion phase. This phase may not occur because the officer is responding to a crash, a call for assistance, or the stop was the result of a roadblock.
This phase involves an officer observing the vehicle in operation and looking for visual cues of impairment. There are four types of visual clues an officer is looking for when deciding to make a DUI traffic stop: proper lane position problems, speed and braking problems, vigilance problems, and judgment problems. Lane position problems include weaving, drifting, and swerving. Speed and braking problems can look like unnecessary acceleration or deceleration, varying speed, or travelling 10 mph or more below the posed speed limit. However, speeding is not an indicator of impairment. Vigilance problems may be cited if the vehicle is in operation without headlights on, driving the wrong way, or slow to respond to traffic signals. Finally, judgment problems may include following too closely, improper lane changing, or illegal or improper turning.
Phase Two: Personal Contact
The second phase of a DUI investigation is the Personal Contact phase. This phase begins when the officer approaches the driver of the vehicle. Typically, this will occur either during the initial interactions during a traffic stop or during the officer’s crash investigation. The Personal Contact phase requires that the officer observe and interview the driver face-to-face. During this interaction, the officer will be looking for auditory, visual, and olfactory clues of impairment. The most common things officers cite as clues of impairment during this phase are slurred speech, bloodshot and/or watery eyes, unsteady gait, and the odor of alcohol or marijuana coming from the person and/or vehicle. These clues help the officer establish probable cause for detainment and arrest.
Phase Three: Pre-Arrest Screening
The final phase of most DUI investigations is the Pre-Arrest Screening phase. In this phase, the officer will typically ask the subject suspected of DUI to perform a series of formal physiological tests. This may not occur for various reasons including a disclosed injury or medical condition, the age of the suspect (65 or older), or other safety risks. Each of the standardized Field Sobriety Tests tests performed by the officer have been verified to test impairment by NHTSA (The National Highway Traffic Safety Administration). NHTSA is the government agency responsible for keeping data related to traffic incidents, doing studies on factors related to roadway safety, and implementing rules and regulations to keep roadways safe for drivers. These rules and regulations include the most widely used field sobriety tests for determining impairment.
The three recognized Standardized Field Sobriety Tests (SFSTs) are the Horizontal Gaze Nystagmus, the Walk and Turn, and the One Leg Stand. Each of the field sobriety tests can provide an officer with a number of clues regarding impairment that we will discuss in detail for each of the tests.
The Horizontal Gaze Nystagmus (HGN) is a test that involves the officer checking a subject’s eyes and watching for various clues that may indicate impairment. Without getting into too much scientific detail, nystagmus is an involuntary jerking of the eye that can occur as the eyes move from a center point to one side or another. While performing the HGN test, an officer will be looking for any of several clues including: lack of smooth pursuit when moving eyes side to side, distinct and sustained nystagmus when eyes are fully to one side or the other, and the onset of nystagmus before the eyes are at maximum deviation.
The Walk and Turn test is divided into two stages: the instruction stage and the task stage. During the instruction stage, the officer will ask the subject to stand with one foot in front of the other on a line with their hands at their sides while the officer gives the instructions for the test. The officer will be watching to see if the subject is able to keep his/her balance and if the subject starts the task too soon. The task itself requires that the subject take nine heel-to-toe steps down a line, then, keeping the lead foot planted, pivot to turn around, and finally take nine heel-to-toe steps back. While doing this test, the subject should keep their hands at their sides and count both sets of nine steps out loud. The clues of impairment during this stage are failure to continue walking, missing heel-to-toe, stepping off the line, using arms to keep balance, taking an improper number of steps (either too few or too many), and making an improper turn.
Finally, the One Leg Stand test involves a subject’s ability to balance and count for thirty seconds. During the instructions for the test, the subject must stand with his/her feet together, arms down at their sides. For this test, the officer will instruct the subject to choose one leg to stand on, lifting the other approximately six inches off the ground, while counting until the officer tells the subject to stop. The clues of impairment that the officer is looking for are that the subject sways while balancing, uses arms to balance, hops, and puts their foot down.
Contact an Experienced DUI Attorney
None of these field sobriety tests are fool proof. There are multiple reasons other than intoxication that a person might show signs of impairment during these tests. Maybe you have a bad back, an old knee injury, diabetes; any number of these medical conditions and many more can produce signs of impairment unrelated to alcohol consumption.
In any case, it is important that you have an attorney who will leave no stone unturned when it comes to taking care of your case. At May & McKinney, our team of experienced attorneys will fight to make sure your case is properly handled.
Contact May & McKinney, PLLC, if you are facing criminal charges in Tennessee!
