The National Highway Transportation Safety Administration (NHTSA) spent years researching field sobriety tests commonly used across the United States. The goal was to establish a set of standardized field sobriety tests, in order to improve the accuracy and reliability of this testing. They accomplished this goal in 1981.
While many field sobriety tests have been used for years and still are, in some states, there are only three field sobriety tests that have been officially approved and standardized, by the NHTSA. The tests are standardized, meaning that the officers are trained with a specific set of instructions on how to perform these tests.
Rather than rely on so much subjectivity, the officer strictly follows this set of instructions to ensure the best results of the test. The three standardized tests are the one-leg stand, the walk and turn test, and the horizontal gaze nystagmus (HGN, or pen test).
In many states, these are the only field sobriety tests allowed as admissible evidence in a DUI trial. But, in others, non-standardized testing is still used and provided as evidence of an individual’s impairment, at the time of arrest.
Some examples of popular, but non-standardized tests are the alphabet test, the hand pat test, and the finger to the nose test. It is important for someone who has been charged with a DUI to know what tests are standardized and which are not and what his or her rights are. A DUI lawyer can help determine if testing was inappropriate or inaccurate and help a DUI suspect defend his or her case in court.