Standardized Field Sobriety Tests


            If I asked you what picture comes to mind when you hear the words “I was pulled over for a DWI”, it is probably an image like this: a nervous person on the road side in the dark with flashing police cruiser lights in the background walking on an imaginary tight-rope and desperately trying not to step off the invisible line.  This imaginary citizen is being subjected to what are called “Standardized Field Sobriety Tests”.  These are a battery of three pseudo-scientific tests promoted by the National Highway Traffic Safety Administration (NHTSA) and meant to assist officers in determining whether a person has had enough to drink in order to impair their physical and mental capabilities or put them over the legal limit for blood alcohol content.

            As a Texas DWI trial attorney, I have studied the NHTSA manual and work hard to keep up on the latest tactics to ensure that these tests are being performed accurately and educate juries on the weakness of the tests even if performed correctly.  The three tests are the Standardized Field Sobriety Tests are the Horizontal Gaze Nystagmus (HGN), the Walk and Turn, and the One Leg Stand.

            Of the three tests, the HGN test is perhaps the most preposterous.  It supposes that a police officer, with a few hours of training, can conduct an ophthalmological examination in the dark, outside, while standing up, on a nervous subject who has given them limited or no medical history.  It assumes that this officer has judged the correct distance from the subject, can actually discern the microscopic fluctuations in the pupil as it tracks the stimulus, and can eliminate the literally dozens of alternate causes for abnormal eye movement that have nothing at all to do with intoxication.  As a criminal defense attorney, I relish the chance to attack this test in a DWI trial or ALR hearing.

            The other two tests that officers use to determine intoxication in drivers, the walk and turn and the one let stand, fail to take into account physical differences between people and can be great areas for cross examination of officers in a DWI trial.  Often the officers give the instructions in such a manner that it would be nearly impossible for a sober person to follow them, and then make the citizen being accused of DWI stand for as long as it takes for them to wobble.  Try it on your own.  How long could you stand in the dark without using your hands for balance, and how many perfect heel-to-toe steps can you take on the side of the street at night?  These tests are designed to encourage failure, so don’t be surprised if you don’t do as well as you thought you would.  The good news is that a skilled DWI trial attorney can use these tests to your advantage at your trial.  Call my office today to discuss your DWI arrest and possible defenses for us to use at your trial and ALR hearing.

            Shawn H. Smith is an experienced Criminal Defense and DWI attorney serving the counties of Bexar, Guadalupe, Hays, Comal, Kendall, Wilson and more.  Call today for your free consultation, available nights and weekends for your convenience.


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