Contrary to popular belief, if you are pulled over and the officer suspects that you are driving under the influence you do not have to perform field sobriety tests. You are required to submit to a chemical breath or blood test that is performed after arrest, but field sobriety tests (FSTs) are done prior to arrest and are not required by law. FSTs are designed to make you fail. They are often difficult to complete even by a sober individual. How you perform on a field sobriety test can be greatly affected by things such as your weight, age, time of day, area where it is conducted and the instructions given by the officer.
The National Highway Traffic Safety Administration (NHTSA) states that there are only three standardized Field Sobriety Tests. All other tests are not scientific and are not good indicators of a person’s sobriety or intoxication.
Standardized Field Sobriety Tests
Horizontal Gaze Nystagmus (HGN) – the involuntary jerking of the eyes as they gaze toward the side. While this occurs naturally, HGN may occur sooner when a person is intoxicated. An officer holds a stimulus in front of the subject and then moves the stimulus from smoothly across their field of vision looking for three “clues” to determine intoxication:
- Lack of smooth pursuit
- Distinct and sustained nystagmus at maximum deviation
- Onset of nystagmus prior to 45 degrees
Walk and Turn (WAT) – requires a subject to walk nine heel-to-toe steps down a real or imaginary line, turn and walk nine heel-to-toe steps back. The Walk-and-turn test has two distinct stages: instructional stage and walking stage. The officer looks for the following clues:
- Inability to keep balance during instructions
- Starting prior to instructions being finished
- Stopping while walking
- Not stepping heel-to-toe
- Stepping off the line
- Using arms to balance
- Improper turn
- Incorrect number of steps
One Leg Stand (OLS) – requires a subject to balance on one leg for 30 seconds. This test is also broken into two stages: the instructional stage and the balance and counting stage. The officer looks for the following clues to determine intoxication:
- Swaying while balancing
- Using arms for balance
- Hopping
- Putting foot down
Each of these standardized field sobriety tests require specific instructions and circumstances to be accurate. Many times officers will not perform the tests according to NHTSA requirements and therefore render the tests inaccurate. If you have been arrested for driving under the influence in San Diego and performed field sobriety tests, call the DUI Defense Law Group to discuss your case and the possible defenses.