Louisiana drunk driving: The HGN test — what is the purpose?

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Louisiana drunk driving: The HGN test — what is the purpose?

on Behalf of

  |   May 25, 2017

  |  drunk driving

Many question whether field sobriety tests that are used to check drivers for impairment are accurate. The National Highway Traffic Safety Administration believes that they are accurate enough to continue using them. Does that mean that those in Louisiana who are charged with drunk driving cannot fight the results of such tests? No.

There are three standardized field sobriety tests, two of which were addressed in previous posts. This week, this column will review the horizontal gaze nystagmus. Topics to be discussed will include what officers are looking for and how the test is performed.

The HGN test is not a balance test like the walk-and-turn or one-leg stand tests. Instead, an officer will be looking at one’s ability to smoothly and accurately track an object with one’s eyes. According to the NHSTA, it is a sign of impairment if one’s eyes jerk or bounce during testing.

Before any field sobriety test is administered, the law enforcement officer on scene will have to first provide verbal instructions about how to perform the test. The instructions for the HGN are quite simple. Follow with one’s eyes whatever object the officer asks one to look at. The officer will then hold the object 12 to 15 inches from the person’s face and begin moving it side to side.

Like the other field sobriety tests, errors can occur during the HGN administration process. Louisiana residents who have been charged with drunk driving and believe that this is the case can fight the results in court. An experienced criminal defense attorney can help accomplish this by questioning the officer’s actions and by reviewing any prosecution evidence to be offered in court.

Source: FindLaw, “What Is Horizontal Gaze Nystagmus (HGN)?“, Accessed on May 24, 2017

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