Phoenix DUI Lawyers Explain More about the DUI “Eye Jerk” Test

When you are pulled over for a DUI in Phoenix, it is likely that the officer will ask you to perform some field sobriety tests in order to assess whether or not you have been drinking. Among those tests is the horizontal gaze nystagmus (HGN), which tests how your eyes track an object and involuntary eye movements (usually the officer will test this using a pen or finger). The officer is looking for a tell-tale twitch or jerking motion of the eye, which is indicative of intoxication.

What's the Problem with the HGN in Arizona DUIs?

Although, in theory, the HGN should be a helpful indicator of intoxication, it raises many concerns in practice. As Phoenix DUI lawyers, we’d like you to know about the problems with the HGN test during a DUI stop, including:
  • Non-medical training of officers. Generally, police officers in Arizona complete a weekend-long training course that covers field sobriety tests, including the HGN. The trainers are usually also officers, and they are generally not medically trained to administer and interpret the results. 
  • Improperly administered testing. For the HGN test to give the most accurate results, your head must stay still, the object used must be a certain distance from you, etc. In actual practice in the field, these tests are often administered improperly, especially if the potential offender has been observed to be unsteady on his or her feet.
  • Other conditions may cause similar results. Intoxication is not the only condition that can give a positive result for the HGN. Neurological disorders, ear infections, epilepsy, and even high blood pressure are among the numerous conditions that could cause a false positive on a DUI eye test in Arizona.

If you have been pulled over for a DUI in Phoenix and have questions about field sobriety tests or what to do next, please don't hesitate to speak with one of our highly experienced Phoenix DUI lawyers today at 1-888-929-5292. Additionally, we encourage you to learn more about your rights and options with a FREE copy of our must-read book, DUIs in Arizona - What You Must Know.