Why You Might Fail A Sobriety Test, Even When You’re Sober

Cop pulling over car

Getting pulled over can be a nerve-wracking experience no matter the circumstances. However, if a police officer suspects you’ve been drinking and administers a field sobriety test, you’re likely going to feel confused, overwhelmed, and scared.

While field sobriety tests are common across the country, they have several faults. Most notably, it’s possible to fail a sobriety test even if you’re sober.

Understanding Field Sobriety Tests

3 Main Types of Field Sobriety Tests

Currently, there are only three standardized field sobriety tests that law enforcement can administer.

The Horizontal Gaze Nystagmus Test

Typically before this test begins, the officer will look at your eyes for signs of impairment, like redness and dilated pupils. If they suspect you’re under the influence of drugs or alcohol, they’ll perform the horizontal gaze nystagmus test.

The officer will hold a small object (often a pen) approximately one foot away from your nose and slowly move it from one side to the other. Drivers will be asked to follow the object by moving their eyes and not their head.

Walk & Turn Test

First, an officer will give instructions regarding the test. While explaining the test, you’ll be asked to stand heel-to-toe and with your arms at your side. After the officer explains and demonstrates the test, you’ll be asked if you understand.

Then, you’ll be asked to walk in a straight line (either a real line on the road or an imaginary one), taking steps heel-to-toe. You may also be asked to keep your arms to your side, look at your feet, or count out loud.

The One-Leg Test

During this test, officers will ask you to stand with one foot roughly six inches off the ground and count out loud by thousands (one-thousand-one, one-thousand-two, etc.) until you’re asked to put your foot down. The test usually lasts around 30 seconds.

You may also be asked to keep your eyes on your elevated foot with your arms at your side.

What is a non-Standardized Field Sobriety Test?

Sometimes officers will ask a driver to write or recite the alphabet (sometimes backwards) or count out loud in reverse. However, these types of tests are not standardized because they’re not scientifically proven to accurately test for impairment.

Why You May Fail a Field Sobriety Test

Believe it or not, it’s not uncommon for sober people to fail a field test. Common factors that will cause someone to fail include:

  • A physical disability. A physical disability can make it hard for someone to walk heel-to-toe or in a straight line.
  • Loud roads. Hectic or loud roads can cause a person to feel scared or overwhelmed. It can also make it difficult for them to hear the instructions.
  • Not understanding instructions. Whether because you could not hear the instructions or did not understand them, a simple misunderstanding can cause you to fail a field test.
  • Fatigue. Tiredness can mimic many of the same “symptoms” as alcohol or drug impairment.
  • Medical reasons. Similar to a physical impairment, a medical condition, such as vertigo, can affect a person’s ability to walk in a straight line or keep their balance on one foot. Certain prescription medications can also affect your eyes, causing them to look glassy or bloodshot when you’re sober.

Are Field Tests Covered Under Implied Consent?


When you get your driver's license, you automatically consent to a breath alcohol test (breathalyzer) if you’re pulled over by law enforcement under suspicion of drunk driving. However, field sobriety tests are not included under implied consent laws, so you may be able to refuse them if asked.

If You’re Charged with a DUI, Contact Kenneth Belkin

Police officers often forget that sobriety tests are not always appropriate or fair. From physical conditions to nervousness and anxiety, there are dozens of reasons why someone may fail them, other than alcohol or illegal drug use. Do not fear fighting unfair tests by the prosecution when you have Kenneth E. Belkin, Esq. at your side.