Using a Mississippi DUI Lawyer to Challenge SFSTs

There’s ample evidence to show that there is no correlation between performance on field sobriety tests and the ability to drive.

WIt’s been proven scientifically that standardized field sobriety tests (SFSTs) are not a reliable indicator of whether someone is under the influence. Simply put, a sober person can fail an SFST just as easily as an intoxicated one.

Why, then, are SFSTs used? Because they’ve been accepted by law enforcement and judges as being valid, largely because of the work of the National Highway Transportation Safety Administration, a federal agency that is part of the Department of Transportation. NHTSA first developed SFSTs in the mid-1970s, and three tests in particular have become the most commonly by police: horizontal gaze nystagmus, walk and turn, and one leg stand.

If you were arrested for DUI after performing these or other tasks at the request of law enforcement, contact a Mississippi DUI lawyer for help. The validity of SFSTs can and should be challenged in court. It can be the key to your DUI defense. For instance, the walk and turn test is great at determining whether someone is physically coordinated and balanced…not so great at detecting impairment due to alcohol or drugs. NHTSA itself has noted that some people have trouble with balance even when sober. Additionally, the original research indicated that individuals over 65 years of age, or with back, leg or middle ear problems had difficulty performing this test. It is crucial that in administering the test, the officer provide a designated straight line on which to walk. Failure to do so is grounds to challenge the test results.

The same is true for the one-leg stand. Issues here may include the surface on which the driver was standing (slippery, sloped, soft) and the type of shoes worn. Also, you should carefully analyze whether the officer correctly scored the test using the four standardized clues, or used non-standardized clues. The four clues are using arms for balance, swaying, hopping, and putting down the foot before finishing.

The third SFST is the horizontal gaze nystagmus. Nystagmus is an involuntary jerking of the eye and may be evidence of intoxication, but may be caused by other factors. These can include neurological disorders, brain damage, weak vision in one eye, even irritants such as dust or wind.

Studied in the laboratory by expert researchers, SFSTs have shown their inaccuracies. A 1987 study concluded that the tests do not accurately measure driving impairment. Researchers recognized that such tests are designed to determine balance, steadiness, and reaction time but concluded that a connection between these factors and driving ability “is not apparent since neither a steady stance nor simple movement time is essential to the safe operation of a motor vehicle.”

Even more telling, a 1991 study had 21 individuals perform a battery of SFSTs. These were videotaped and shown to 14 police officers. 46% of the time the officers concluded that the subjects were too impaired to drive. How much had the subjects in the video had to drink? Absolutely nothing. Each had a blood alcohol content of .00 percent.

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