- What Are Field Sobriety Tests?
- Standard Field Sobriety Tests
- The One-Leg Stand
- HGN - Horizontal Gaze Nystagmus
- Non Standardized Field Sobriety Testing
What Are Field Sobriety Tests?When you are pulled over under the suspicion of drunk driving, you will most likely be subjected to a series of roadside field sobriety tests. The tests are generally divided into two categories – standard FST and non-standard FST. Standard field sobriety tests have been subjected to scientific testing and are very reliable. Most non-standard tests have not been subjected to scientific testing. Therefore, they aren’t considered as valid as
Standard Field Sobriety TestsSFSTs are conducted to determine the level of a driver’s impairment, and they consist of HGN, also known as horizontal gaze nystagmus, the walk-and-turn, and the one-leg stand.
HGN - Horizontal Gaze Nystagmus
During this test, the police officer looks for and observes involuntary eye movement known as eye bouncing or jerking. The test is usually conducted by moving an object such as a pen or a finger side to side in front of an individual’s face. The individual has to follow the pen or a finger with his eyes, and the head mustn’t move. The officer looks for the following three indicators of impaired driving:
Jerking of the eye while following the object
Distinct and sustained nystagmus at maximum deviation. This means the eye will continue bouncing from the corner of the eye opening when the observed object is way out to the sides of the suspect’s face
The angle of involuntary eye movement starts 45-degrees of center. Depending on the number of observed clues, you can score on from 0 to 6 points. Both eyes should be tested because nystagmus is symmetrical. If you score 4 points on the test, it indicates that your BAC is 0.10% or higher.
The walk and turn is conducted by taking nine heel-to-toe steps following a straight line, turning on one foot, and taking nine steps back to your starting point. The law enforcement officer will look for the following clues of impairment: Failure to balance while listening to instructions Beginning before instructions are finished Stopping in order to regain balance Stepping off the straight line Using arms to keep balance Turning back improperly Failure to take the correct number of steps Two or more clues indicate your BAC is 0.10% or higher.
The One-Leg Stand
This test is conducted by standing on one leg with your foot approximately six inches off the ground and count aloud to 1000 or another specific number, or until the police officer tells you to stop. The examiner is looking for the following four clues of impairment: Swaying and struggling to keep balance Using arms or hopping to keep balance Putting your foot down. The foot must be above ground for 30 seconds. Two or more clues indicate that your BAC is 0.10% or higher. In most cases, these tests are true, and they are considered valid in court.
Non Standardized Field Sobriety TestingNSFSTs are defined as any other mental or coordination test a law enforcement officer may give to the suspected driver to determine his level of impairment. These commonly include the Rhomberg balance test, finger-to-nose test, finger count, hand pat test and so on. The officer may ask the suspect to recite part of the alphabet or to count backward.
The Rhomberg balance evaluation is often used and consists of standing with your feet together and leaning the head back to look up at the sky while holding your arms out to the side. This way, the officer checks your balance. The finger count test is also often conducted and requires the driver to touch the tip of his thumb in turn to the tip of each finger on the same hand and count from one to four, then to go backward counting in reverse.