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Horizontal Gaze Nystagmus (HGN) Jacksonville FL

If you are stopped for drinking and driving, the police officer will likely conduct the DUI field sobriety test called the horizontal gaze nystagmus (HGN) test. The problem is that this test is more of an eye examination and because police are not trained in the areas of ophthalmology there is significant question regarding the reliability of this test relative to DUI suspicion.

The term "nystagmus" refers to "an involuntary jerking or bouncing of the eyeball that occurs when there is a disturbance of the vestibular (inner ear) system or the oculomotor control of the eye." In laymen's terms, horizontal gaze nystagmus is basically a horizontal jerking that occurs when the eye looks to the side. The reason this is used during DUI testing is because it is believed that when someone has been drinking alcohol the brain's ability to control the eye muscles is significantly hindered. As one's consumption of alcohol increases, so does the amount of jerking or bouncing of their eyeball.

If a police officer suspects you have been drinking and driving, he or she may choose to administer the HGN test to look for various clues to indicate impairment leading ultimately to a DUI charge. During the HGN test, the officer must be able to see your eyes clearly and often may use a flashlight to aid in visibility. You will be asked to follow an object with your eyes such as a pen or penlight. The object will typically be placed 12 to 15 inches from your face and slightly higher than eye level.

The problem lies in the fact that a large percentage of the population naturally displays nystagmus or "jerking" of the eye and without proper medical training, it can be difficult to distinguish between naturally occurring horizontal gaze nystagmus with horizontal gaze nystagmus due to impairment. In fact, nystagmus can be caused by other factors besides alcohol consumption including neural or muscle activity, eye strain, brain damage, brain tumors and inner ear diseases.

That is why it is so critical to speak with a qualified DUI lawyer like Casey Bryant if you are charged with a DUI. Because Casey has worked on hundreds of DUI cases, he is intricately versed in the laws surrounding drinking and driving and can help defend you if you've been inaccurately tested.

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