Failed field sobriety tests are not always proof of inebriation

On Behalf of | Dec 29, 2020 | Drunk Driving Defense

A traffic offense gives the officer probable cause to stop you. However, to have enough evidence to show reasonable suspicion and justify an arrest, he or she may ask you to take field sobriety tests.

Science has validated that these tests, properly administered, do indicate when a driver has had too much to drink. According to AAA, science has also shown that the results are not conclusive. Here are some ways that the standardized field sobriety tests may return false results.

Horizontal gaze nystagmus

As you follow the officer’s pen, finger or flashlight from side to side, he or she is watching for your eyeballs to jerk involuntarily. In medical terms, this jerking is “nystagmus,” and it is usually present in people with a BAC of 0.08% or higher.

You may also have HGN due to one of these other issues:

  • You take certain medications
  • You have an inner ear condition
  • You have a central nervous system disease
  • You were born with it
  • You have albinism

The walk-and-turn and one-leg stand tests

An officer wants to test your balance and your ability to follow instructions, as well. If, while you walk in a straight line heel to toe, you wobble, step off the line or take the wrong number of steps, you have displayed signs of inebriation. Likewise, if you cannot balance with one foot in the air for 30 seconds without swaying, hopping or putting your foot down, the officer notes that you may be drunk.

Some of the same health conditions that affect HGN also cause balance issues, including medication, inner ear inflammation and a number of diseases. You may have difficulty following the directions due to anxiety from an interaction with law enforcement, ADHD or some other attention issue.

Studies proved that the HGN test is wrong about 12% of the time, the walk-and-turn is wrong about 21% of the time and the one-leg stand is wrong about 17% of the time. If you fail the tests, and even if a chemical test shows you have a high BAC, you do not necessarily have to resign yourself to a DWI conviction.