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Horizontal Gaze Nystagmus (HGN)

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The Horizontal Gaze Nystagmus, or HGN test, is a field sobriety exercise (or roadside test) conducted by police officers during the course of a DUI investigation.

This is the test where officers place a stimulus, usually a pen, in front of your face and have you follow it with your eyes.
Nystagmus is an involuntary twitching of the eye muscle. If you are impaired by alcohol or drugs, your eyes will shake or flutter when asked to follow a pen across a smooth plane. Also, police believe that if your eyes shake or flutter when they are holding the pen out past your shoulder (maximum deviation), or begin to shake before the pen reaches your shoulder (45 degrees), then the only conclusion is that you must be drunk.
This HGN test allows officers to check for three things:
1) Do you have equal tracking in both eyes?
2) Do you show the onset of nystagmus prior to 45 degrees?
3) Do you show nystagmus at maximum deviation?
What does this mean in English?
1) Equal tracking means that your eyes can smoothly follow a pen without twitching or jerking. If your eyes do not smoothly follow the pen, you will fail this portion of the test.
2) Police estimate an invisible line from your shoulder to your head, and claim that it equals a 45 degree angle. Police officers are trained that if your eyes begin to shake or twitch before the pen reaches that 45 degree angle (your shoulder), you are drunk and will fail you on this portion of the test.
3) The police officer conducting the HGN test will move the pen in front of your face and out past your shoulder, where he will hold it. This is called maximum deviation. If your eyes flutter or twitch while focusing on the pen, the officer will fail you and conclude that you are drunk.
Police officers are not eye doctors. They are people of ordinary intelligence who have received hours of DUI training from other cops. They have not spent years in medical school studying the anatomy of the human eye. The HGN test has questionable reliability, but when it is administered by an untrained officer, the margin for error is huge.
You have a right to refuse to take the HGN test, as well as all other roadside tests. Mind you, if you refuse, you will likely go to jail. But at least the State's evidence against you will be minimal.
I love attacking police officers when it comes to their training and experience with the HGN test. Their training, for the most part, is pathetic. Only a trained physician should really be permitted to administer the HGN test. But the State of the law in Florida permits police officers to administer this scientific test on DUI suspects.
Imagine - a 22-year-old police officer with only his basic police academy DUI training under his belt, administering a test whereby he is going to determine your level of intoxication by studying and measuring the movements of your eye?
I am a Miami-Dade County DUI attorney who practices in Miami-Dade and Broward County. I fight every DUI because the penalties are so harsh. First DUI penalties include a mandatory conviction and six-month license suspension. Second DUI penalties may include mandatory jail time. Third and subsequent DUIs can be charged as felonies. And DUIs with serious bodily injury (SBI) or death (DUI manslaughter) can land you in prison for years.
Police and prosecutors in Miami and Broward are notoriously tough on DUIs. And with DUI penalties being set by the legislature, judges have no room for discretion, nor do prosecutors. The sentences are what they are - plain and simple.
Don't plead guilty, don't concede defeat. Call me today to discuss your case.