Field Sobriety HGN Test in Atlanta
The field sobriety test known as the Horizontal Gaze Nystagmus Test (HGN), is one of the three standardised field sobriety tests (SFSTs) used by Georgia police and state patrol as a way to determine whether a person may be driving under the influence of drugs or alcohol.
Horizontal Gaze Nystagmus Test
The HGN test is an eye test where the police officer instructs the driver to follow with their eye some object, such as a pen or small flashlight. The object is moved horizontally, back and forth. During this test, law enforcement is watching to see at what angle the eye begins to demonstrate some involuntary jerking movement, or “nystagmus.” This is recorded as a measure related to blood alcohol levels. However, involuntary eye movement including jerking motions occur naturally when the eye is rotated at high angles.
Atlanta Police HGN Test Training
Formalized training has been developed in conjunction with the National Highway Traffic Safety Administration (NHTSA). They have cited the importance of proper standardized training in using the results of these standardized field sobriety tests. The training undertaken to properly administer the HGN eye test is highly specific and specialized.
Understanding exactly how the police instructed the driver in doing an HGN test may reveal improper techniques that would render the test results inaccurate. For this reason, DUI defense lawyers who are certified in training officers to conduct field sobriety tests are in a better position to question police, and analyze their findings.
Correct Administration of the HGN Eye Test
To properly administer the horizontal gaze nystagmus test, it should be done in a well lit area, or with a flashlight to ensure the subject's eyes can be seen clearly. The driver should not be facing the police car's flashing lights, or headlights of other cars. The officer is supposed to tell the driver they are going to check their eyes and ask if they have any medical issues which could affect the test results. While officers are trained, certified, and undergo refresher courses in field sobriety testing, the police or state patrol may incorrectly administer the test, either accidentally or on purpose.
Limited Use of the HGN Test
While the NHTSA, Georgia State Patrol, and Atlanta Police Department use the HGN test to identify intoxicated drivers, it may also incorrectly identify sober drivers as intoxicated. One example includes seizure medication which makes the eyes react in a similar fashion to alcohol consumption. Additionally, there are many outside factors that could make the test subject appear to fail the HGN test even if they are not impaired. This includes flashing police lights and the headlights of passing cars which can trigger jerking eye movement even without alcohol.
According to the NHTSA, the HGN test is one of the most accurate of the standardized field sobriety test, however even they acknowledge that there are a number of innocent, sober people who will “fail” the test, even when properly administered. There is still dispute in the legal and medical community as to the accuracy of such tests, even under optimal conditions.
Georgia DUI Defense Lawyer
If you have been charged with driving under the influence anywhere in the Metro Atlanta area, or North Georgia counties, you need the courtroom experience of a DUI lawyer who knows field sobriety testing. A DUI arrest does not mean a conviction. I am a certified instructor in teaching the police how to administer field sobriety tests, and will my knowledge to get your charges dropped. Call me now, anytime day or night.