People in Virginia who are arrested for driving under the influence offenses after supposedly failing one or more of the field sobriety tests used by officers should know that these tests are not 100-percent accurate. According to FieldSobrietyTests.org, the individual accuracy rates of these three tests ranges from a high of only 77 percent to a low of 65 percent.
Among the factors that may inhibit a person from successfully passing these tests is a person's health. The ability to balance perfectly is one factor evaluated in two of the tests, the walk-and turn test and the one-leg stand test. A person who is heavy naturally can have a harder time balancing properly than can a slim person. Ear infections or other issues in the inner ear canal are known to interfere with balance. Any injury or medical condition involving the back, hips or the joints or soft tissue of the lower limbs may also make passing these tests all but impossible.
When evaluating the eye motion of a driver in the horizontal nystagmus gaze test, it should be known that there are neurological conditions that may cause a person's eye to jerk in such a way that makes an officer conclude the driver may be intoxicated.
If you would like to learn more about the three tests used in a roadside investigation for suspected drunk driving and the potential issues with their accuracy, please feel free to visit the field sobriety test page of our Virginia criminal and DUI defense website.