Nystagmus is the involuntary movement, or jerking, of the eye. The factors that can create this sort of reaction from the human being include spinning in a circle, alcohol altering the gravity in the blood, watching images which are sharply contrasting each other and pathological disorders.
The eye test, also called HGN test, is almost always performed whenever a law enforcement officer is trying to find probable cause to arrest someone for dui (DUI).
When a law enforcement officer is ready to perform this test, they will stand in front of you. They will ask you to look at a pen, flashlight or finger. After this,they will then move the object in front of you back and forth by your face. While the police officer is doing this, they’re attempting to find the following clues.
The first clue is lack of smooth pursuit. The law enforcement officer will move their pen, flashlight or finger from side to side. While doing this, they will tell you to follow the thing with your eyes only, If indeed they find any nystagmus, you will fail the test.
The second clue is nystagmus at maximum deviation. When the officer holds a persons gaze at the corner of their eye for four seconds, they believe a drunk person will have eyes which are bouncing around a lot more than a sober people eyes would.
The last clue an officer is looking for would be to see if a person shows nystagmus prior to their eyes coming to a -degree angle. NHTSA guidelines claim that nystagmus ahead of educations is a sign of an individual having a BAC of over ..
Is this test valid?
For this test to be valid, an officer has to make sure the check is performed in compliance with NHTSA guidelines. Many times these tests aren’t done based on the suggestions. This is why you need to call a dui defense lawyer asap in case you are arrested for dui.