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What is a field sobriety test?

| Sep 7, 2021 | Drunk Driving

Field sobriety tests are one way for the police to determine if you are too drunk to drive. If they stop you and ask you to step out of the car, this may be what is coming next.

When a police officer asks you to take the field sobriety tests, they are looking for a reason to arrest you and charge you with drunk driving. Failing would give them the grounds they need to arrest you. It does not, however, guarantee a court will convict you on drunk driving charges.

The police use three principal field sobriety tests

One test alone does not give sufficient evidence that you are unsafe to drive. However, a study found that combining these three tests yields a 90% accuracy rate:

  • Walk-and-turn test: Officers generally want to evaluate how well you walk along a straight line. They may have you take a certain number of steps forward along a line in the road, then have you turn around and walk back. While it seems simple enough, nerves or a leg injury could cause you to fail.
  • Horizontal gaze nystagmus: This is the test where a police officer has you follow a pen with your eyes. If your eyes jerk around too much, then you will fail it. A plausible explanation for why you might have difficulty staying focused on the pen is having allergies that cause you to have an itchy nose. 
  • One-leg stand test: A police officer may have you balance on a single leg as part of this test. While this doesn’t sound overly challenging to do in theory, give it a try, and you’ll quickly see that it’s difficult to do even if you haven’t been out drinking. 

There are many ways to defend yourself against DUI charges if prosecutors brought them because you allegedly failed a field sobriety test. You can challenge how the officer carried out the test and why they pulled you over in the first place. You may have medical and other reasons to explain why you did not pass to present at trial as well.