The Horizontal Gaze Nystagmus test is one of only three standardized field sobriety tests (SFST) used in the state of Georgia to gauge a driver's ability. You may have also heard it called the "follow this pen with your eyes" test.
What exactly is "Nystagmus"
It is the involuntary jerking of the eyes that can be sometimes caused by excessive blood alcohol.
Can other things cause Nystagmus?
Yes! Lack of sleep, caffeine and cold remedies are the most common reasons. Some of these factors exist in the overwhelming majority of DUI cases.
If I fail this test, will I be arrested?
Possibly. But it is important to remember that SFSTs are designed only to be used in deciding whether to arrest an individual, not as substantive evidence at trial.
You should consult a local DUI attorney to find out your rights.