It is a given. Law enforcement officials and prosecutors want as much evidence against you to convict you of driving under the influence. That is one reason why all law enforcement officers use the same standardized field sobriety tests, or SFSTs, when stopping you for traffic stop. These standardized tests were created by the National Highway Traffic Safety Administration, or NHTSA. Police use one or more of these tests to determine whether you are drunk or not.
Standardized Field Sobriety Tests Explained
The three standard tests determine whether you are drunk by allowing police to observe your behavior. These tests are supposed to be easy to perform when you are sober and hard to complete when you are allegedly drunk.
A police officer will tell you to place one leg about six inches from the ground and stand on the other. You’ll have to do this for approximately 30 seconds. A sober individual is supposed to complete the task with no problem. Failing the one leg test involves things like:
- Using your arms to keep from falling.
- Swaying as you stand on one leg.
- Consciously or subconsciously placing your foot on the ground.
Law enforcement officials claim that the one-leg stands is 83 percent accurate. It can detect a blood alcohol concentration, or BAC, level of 0.08 percent or higher.
Nystagmus causes a person to involuntarily look from side-to-side in a swinging, rapid motion rather directly at a fixed object. In some extremely bad instances of nystagmus, an individual’s eyes jerk sideways or in an up and down motion. To some degree, everyone has some form of nystagmus whether impaired or not. However, the level of nystagmus can become exaggerated when a person is under the influence of alcohol.
To determine if you were driving while under the influence, a police officer will use a tiny object like a pen in front of your eyes. Then he or she will slowly move the object from side-to-side. You will be instructed to follow the small object with your eyes only. You cannot move your head at all.
During this sobriety tests, a police officer is looking for indications that you are drunk like:
- The inability to smoothly follow the object. If you are failing the test, your gaze appears inconsistent and broken.
- Your eyes twitch or jerk.
- The twitching or jerking eye motion occurs within 45 degrees of the center of eyes.
The HGN will test accurately a 0.08 or higher percent intoxication level about 88 percent of the time, according to law enforcement statistics.
Walk and Turn Test
This sobriety test is meant to divide a driver’s attention like the one-leg stand test. The law enforcement officer instructs you to walk nine steps with one foot in front of the other. In other words, walk in a heel toe, heel toe direction. You then turn around and walk in the opposite direction.
If you are intoxicated, the officer will generally notice:
- Poor balance.
- You stop or begin the test without waiting for the officer’s instructions.
- You sway.
- You fail to touch your heel to your toe.
- You use your arms to keep your balance.
The law enforcement statistics reveal that this test is 79 percent effective at actually indicating intoxication levels of 0.08 percent or higher.
Just because law enforcement claims that these standardized tests have a high rate of detecting intoxication does not mean they are always correct. Errors do occur ranging from faulty police instructions to a medical condition. The attorneys at the Law Offices of Jonathan Franklin are experienced in spotting law enforcement errors when they occur. Jonathan Franklin is a former prosecutor who now defends the rights of those accused of DUI. Contact Jonathan Franklin today to schedule your free consultation and find out how he can help your successfully resolve your DUI matter.