The one-leg stand test is one of three field sobriety tests that have been “standardized” by the National Highway Traffic Safety Administration. The three are:
This test requires the suspect to stand on one leg. The other leg is to be extended in front of the suspect in a stiff-leg manner, with the foot held approximately six inches above and parallel with the ground. The suspect is to stare at the elevated foot, and count aloud until told to stop, in this fashion: “one thousand and one, one thousand and two, one thousand and three …”
The officer is instructed to give the test as follows:
The officer is also given the following instruction:
The One Leg Stand has four clues of impairment:
Two or more clues classify the subject as a 65% chance of being over a 0.10% blood alcohol concentration (BAC).
This test requires a reasonably dry, hard, level, and non-slippery surface.
Also, the officer is warned that, based on original research, subjects who were over 65 years of age, had back, leg or middle ear problems, or over 50 pounds overweight had difficulty with this test. Individuals wearing heels more than two inches high should be given the opportunity to remove their shoes.