When a Police Officer Asks Me to Follow an Object With My Eyes, What Are They Looking For?

It’s late at night and you’ve been pulled over. Perhaps you had a drink or two earlier but are no longer feeling the effects, and have even had a bite to eat since then. Still, you’re nervous. 

The police officer seems intent on removing you from your vehicle to conduct a field sobriety test. While you can – and should – legally refuse these tests, many people worry that refusal can be interpreted by police as suspicious. As a Pennsylvania driver, you’re also driving under the assumption of consent. That means you automatically consent to breath or blood tests, simply by driving legally.

Field Sobriety Tests Are Not Perfect

Field sobriety tests police conduct are full of flaws. 

One of the tests in the common battery developed by the National Highway Traffic Safety Administration (NHTSA) is known as the horizontal gaze nystagmus (HGN) test, where the police officer instructs a suspect to follow an object (such as a finger or pen) with their eyes. 

This test is only about 80% accurate at best, even when used alongside the other tests in the standard field sobriety battery. Making matters worse, there’s no consistent scientific basis for using these tests as evidence for a DUI.

If you’ve been arrested for DUI or have questions about your case, an HGN test may be relevant to your charges. An experienced DUI attorney in Pennsylvania will inform you of your rights and help form a strong defense against all charges. 

Learn more about your legal options and what strategies you could use in your case during a free, no-obligation consultation with Steven E. Kellis. Schedule your free appointment now by calling (215) 940-1200 or contacting us online. 

The Goal of the Nystagmus Test

Here’s what a police officer who asks you to follow an object with your eyes is looking for: your eyes may begin jerking while you move them, especially early on. 

If you try this test with a friend while sober, you’ll likely have no problem moving your eyes slowly and evenly while following the object – though there are some exceptions if you have a medical condition. While under the influence of alcohol, however, it may be more difficult to track the object without a bit of lag or snapping eye movement in order to keep up. This effect is known, medically, as nystagmus.

Problems with the Nystagmus Test

Despite the detailed procedures the NHTSA has laid out for officers conducting this test, law enforcement is known to administer the test incorrectly, resulting in far more false positives than there would be if the test were always executed properly. This could be due to poor training, an absence of training, failure to adhere to training, officer bias, or other external factors.

On top of the human error that can occur when administering a test, it’s not uncommon for nystagmus to be present in adults without any alcohol involved at all. Nystagmus is a diagnosable vision condition, which can be caused for many reasons outside of inebriation. 

Examples of medical conditions that can cause nystagmus include:

  • Albinism
  • Abnormal eye development
  • Inflammation of the inner ear
  • Central nervous system diseases, such as multiple sclerosis
  • Congenital cataracts
  • A high level of nearsightedness or astigmatism
  • Certain medications, particularly anti-epilepsy drugs

Despite the flaws with the test, law enforcement still uses it extensively. For that reason, it’s a great idea to have some awareness of what the police are looking for when conducting this test. 

Better yet, refuse the test and consult with a seasoned Pennsylvania DUI lawyer if you end up facing charges related to driving while under the influence. 

If you’re in such a situation, the law firm of Steven Kellis is available 24/7 to help go over the details of your case. Your first appointment also comes at no charge to you and with no obligation to use our services afterward. Give us a call at (215) 940-1200 or contact us online today to schedule your free case review.