If you are pulled over for a possible DWI in Texas, you will have to take a field sobriety test. A variety of tests is available that you will be asked to complete. You should be aware of them and their varying degrees of accuracy.
The first is the one-leg stand test. This is a straight-forward test on the surface. The subject taking the test must keep one foot six inches off of the ground while keeping their arms at their sides. This is to minimalize one’s ability to balance themselves. At this point, the person must count to 30 before putting their foot back on the ground. This test is designed to show the intoxication of the individual by looking at hints. Hints such as, unwarranted swaying, using arms to balance, hopping in order to balance, putting their foot down and overall, failing to complete the test.
The second is the walk and turn test. The test calls for the tester to walk heel to toe along a straight line, turn and then walk in the same manner back to the beginning. Following the instructions, managing to keep their balance, using their arms to keep balance or fails to take all nine steps can lead the police officer to judge that the tester is intoxicated.
The last standardized test is the horizontal gaze Nystagmus or HGN test. Nystagmus is a form of involuntary eye movement sometimes associated with alcohol use. This is tested by asking the driver to follow a finger or flashlight while keeping their head stationary. The officer is looking for the eye to follow this object smoothly from side to side.
These three tests have varying degrees of accuracy according to research done by the National Highway Traffic Safety Administration in 1998. The one leg stand test was shown to be correct 83% of the time. The walk and turn test was shown to be correct 79 percent of the time. Moreover, the HGN test was correct 88 percent of the time. The reason why all of these tests are standardized is because when the battery of tests is given to one person, they are 91 percent effective. If you are pulled over for a DWI, it is important to know these facts about field sobriety tests.