As a driver in North Carolina, you are subject to the DUI laws of the state. This means you may undergo certain tests if an officer believes you drove under the influence.

One of the first tests you will run into is likely a field sobriety test. There are two types: non-standardized and standardized. The second is most common, and what an officer will probably start off with.

What do these tests check for?

FieldSobrietyTests.org take a look at standardized field sobriety tests, of which there are only three. There is the horizontal gaze nystagmus, the walk-and-turn and the one-legged stand. Each of these tests check for several things, including:

  • Your balance
  • Your concentration
  • Ability to focus on tasks at hand
  • Ability to follow instructions

Symptoms of alcohol in the blood

For example, walk-and-turn tests involve walking along a line while placing your toe against your heel. At the end of the line, you must turn and come back. This tests your ability to balance. Balance is one of the first things affected by high blood alcohol levels. The one-legged stand also tests balance. You must raise your foot off of the ground, usually by about six inches from the ground. You may use your arms to balance.

The horizontal gaze nystagmus (HGN) test looks for something a little different. This test checks for any involuntary jerking of the eyeballs while in motion. This jerking motion happens to everyone. But it is more pronounced if you are under the influence. Thus, a testing officer will have you follow an object with your eyes. They check for how smoothly your eyes track the movement.

These tests have a rubric by which officers must judge them. This is where the “standardized” part of the name comes from. It helps keep officer bias out of the equation and makes these tests a little more fair to you.