Can you fail the horizontal gaze nystagmus test when sober?

You were stopped by an officer for weaving in and out of traffic. He felt like you weren’t being safe, and he asked you if you’d been drinking. You didn’t want to lie, so you admitted you’d had a beer before heading out. That was a mistake. He asked you to get out of your vehicle to take a field sobriety test.

You did well on all parts of the test except for the horizontal gaze nystagmus assessment, or HGN. While your balance wasn’t as good as you would have liked and you didn’t turn and walk as well as you might have without so much stress, the real influence in the arrest was the HGN. When the officer asked you to look to the side, he looked concerned. Your eyes jerked involuntarily, which is a potential sign of intoxication. Along with your admission that you were drinking, he decided to make the arrest. Your blood alcohol content was only .04%.

Can a horizontal gaze nystagmus test be wrong?

Absolutely. There are many reasons why a person might fail this test. Nystagmus on its own doesn’t necessarily signify that a person is impaired by alcohol. It can also happen because of:

  • The movement of fluid in the inner ear
  • Brain damage
  • Eyestrain
  • Neural activity

Since there are potential reasons for you to fail, be sure to be honest with your attorney about any medical conditions you may have that could influence your test. With a low BAC, there may be other reasons for your unusual test results than intoxication.