During an initial consultation with a client following an arrest for Driving Under the Influence, many clients inform me that the officer had them perform a field sobriety test which involves them tracking a stimulus—often a pen or the officer’s finger—with their eyes. Many people mistakenly believe they “passed” this test, as they were able to follow the officer’s instructions and track the stimulus using their eyes without moving their head, as they were instructed to do.
This test is called the “Horizontal Gaze Nystagmus Test,” and is one of the three tests most used by police officers to evaluate a person’s impairment of alcohol. What isn’t told to a person before performing this test, is that it is not primarily used to evaluate a person’s ability to follow directions, but rather to check for nystagmus of the test subject’s eyes. Nystagmus can be described as a slight involuntary jerking movement of the eyeball. Alcohol consumption is one factor that may cause a person’s eyes to exhibit nystagmus, although it is important to note that there are numerous other factors which can cause a person to exhibit nystagmus, including but not limited to: head trauma, strobing lights, medical conditions, fatigue, symptoms of withdrawal, consumption of non-illicit substances, vestibular disorders—and more. Further, there are certain estimated time and distance measurements the police officer must utilize pursuant to their training to properly administer the horizontal gaze nystagmus test.
In the age of greater utilization of video recording devices to capture on-scene investigations, this field sobriety test is distinguishable from others in that the presence of nystagmus will rarely be viewable from recorded video. Consulting with an attorney knowledgeable in the proper administration of this test to help identify errors in the testing process can help devalue its evidentiary use in a DUI allegation levied against you.
This is particularly relevant for driver’s arrested for DUI in New Hampshire, where the State is allowed to utilize this test in a criminal prosecution. In Massachusetts, this particular test has been deemed inadmissible as evidence in a criminal trial, though police still regularly ask those suspected of DUI to perform it to determine if they will arrest somebody for operating under the influence.
Attorney Shane Goudas is a former prosecutor in New Hampshire and Massachusetts. He is licensed to practice law in New Hampshire, Massachusetts, and Texas. If you have been accused of Driving Under the Influence, please feel welcome to contact our law firm at (978) 256-2700 and schedule a free legal consultation.
