The Horizontal Gaze Nystagmus DUI Field Sobriety Test -- Pseudo Science
The horizontal gaze nystagmus test is one of the three “standardized” DUI field sobriety tests. This test (otherwise known as the HGN test) is actually an eye exam. Since most (if not all) police, sheriff, and other local law enforcement officers typically aren’t ophthalmologists…or, for that matter, any type of doctor…they really have no business administering this type of test.
The fact is that a large percentage of the population naturally displays nystagmus, which is nothing more than the “jerking” of the eye. This poses a significant problem, since, when present, officers believe that horizontal gaze nystagmus is an indicator of drug and/or alcohol impairment. Without medical training, it could be difficult to distinguish between naturally occurring horizontal gaze nystagmus with horizontal gaze nystagmus due to impairment.
Add to this the fact that when properly administered and evaluated, the HGN test is only 77% accurate. This means that about one in every four people will be falsely arrested for DUI based on this so called “reliable” field sobriety test.
