SITTING RATHER THAN STANDING DURING HGN (EYE TEST) CAN CAUSE FALSE POSITIVES DURING AN OVI STOP
When a defendant is pulled over by an officer for OVI, officers will ask the driver to perform standardized field sobriety tests (FSTs). Whether the driver passes the FSTs or not often forms the basis of an officer’s decision to arrest for OVI.
One of these FSTs is a Horizontal Gaze Nystagmus (HGN) test, or the “eye test.”
In this test, the officer will use a pen or his finger and track the movement of the eyes. The officer will look for involuntary fluttering of the eye (nystagmus) which, if present, is a possible indicator of impairment.
The National Highway Traffic Safety Administration (NHTSA) did a study to see whether a driver was sitting or standing during the HGN mattered to the result. They said:
“The standard HGN examination is conducted with a suspect standing, feet together, and arms at the sides.”
If someone is in an accident, it might be impossible for an HGN test. In those cases, the test is administered with the suspect sitting or lying down. In the study, participants received an HGN examination standing, sitting, and lying down.
HGN Eye Test While Suspect is Sitting Less Accurate Than HGN Test While Suspect is Standing
The results showed that officers who conducted an HGN test on people who were standing correctly identified whether the individual was impaired or not 91.9% of the time.
However, officers who conducted an HGN test individuals who were sitting were only able to accurately determine impairment 87.7% of the time.
Four percent may seem like an insignificant number, but consider the implications of the 4%. If an officer is 4% more likely to incorrectly determine whether a driver is impaired when sitting, then drivers who are sitting in the cruiser, have been in car accidents, or for whatever reason are unable to stand for the test have an increased chance of failing the HGN test.
Charges of Operating a Vehicle while Intoxicated (OVIs) can vary from case to case and there can be difficulty understanding what defenses may be available to you. It is important to contact an attorney who is knowledgeable about all possible defenses available to you including whether you may have an issue related to the field sobriety tests administered to you. If you have questions about your Columbus alcohol related criminal charges, talk to our defense attorneys at 614-361-2804.
Source: National Highway Traffic Safety Administration. “The Robustness of the Horizontal Gaze Nystagmus Test in Standardized Field Sobriety Tests.” Traffic Safety Facts, Traffic Tech – Technology Transfer Series.
Authored by Anthony Iori, Riddell Law Associate