Usage of One-Leg-Stand Test in Los Angeles DUI prosecutions.
This is a continuation of previous posts on field sobriety tests and how Los Angeles police agencies use it to form a very subjective opinion that a driver is under the influence of drugs or alcohol and therefore drives in violation of Vehicle Code section 23152(a) or 23152(b) (commonly known as DUI statutes).
If during a traffic stop in Los Angeles, a police officer smells alcohol, a driver is likely to be detained for a DUI investigation. An investigation for a DUI in Los Angeles typically involves several field sobriety tests, most commonly: a horizontal-gaze-nastagmus (HGN), a romberg-balance, a one-leg-stand test (OLS), a walk-and-turn (WAT), and a preliminary-alcohol-screening breathalyzer test. Our typical recommendation to clients is not to submit to any of these tests and instead proceed to the “evidentiary chemical test” at a hospital or a police station. However, because most people who are arrested for Drunk driving in Los Angeles do submit to some or all of the field sobriety tests, it is important to discuss the design and reliability of the tests as it will be accepted as evidence by Los Angeles Superior Court. Here, I will only discuss One-Leg-Stand Test, one of 3 tests approved by NHTSA (with the other 2 being a WAT and HGN). NHTSA researchers believe that One-Leg-Stand Test is 65% effective in predicting impairment. The officers who observe the one-leg-stand performance look for 4 clues:
- Swaying when balancing
- using arms to balance
- hopping
- putting foot down
The One-Leg-Stand Test is stopped when a subject can’t do the test or puts his foot down 3 or more times.
Also, when two ore more clues are present, the investigating officer will fail the subject and determine that the blood alcohol level of subject is above the limit. Presence of two clues is important for defense because one clue no matter how bad does not indicate impairment. In other words, using arms to balance or hopping by itself is not an indication of impairment no matter how bad. Similarly, putting a foot down one or two times is also not an indication of impairment. Yet it is possible to fail this test in the eyes of a police officer because the tests are highly subjective, meaning, a police officer might decide that he saw a sway when it fact it was too insignificant for purposes of the test. Either way, the tests 65% reliability and subjective nature of the clues often give sufficient grounds to defend a prosecution that heavily relies on “poor” performance on OLS. To discuss your DUI case call our Los Angeles DUI attorney directly at (818) 921 7744 .