Are Field Sobriety Tests Always Accurate?

January 1, 2022 | By Shane Phelps Law
Are Field Sobriety Tests Always Accurate?

When an officer pulls someone over for a suspected DWI, they will look for signs of impairment. Oftentimes, part of this process is conducting field sobriety tests. Failing one of these tests could result in DWI charges and subsequent penalties. For many, this may feel like the end-all-be-all. However, it is possible for field sobriety tests to produce inaccurate results. The team at Shane Phelps Law is here to review the three standardized field sobriety tests, as well as when they can lead to false DWI charges.

The Three Field Sobriety Tests

There are three field sobriety tests that officers may choose to conduct when suspecting a driver of DWI. They are as follows:

Horizontal Gaze Nystagmus Test

Horizontal gaze nystagmus is when an individual’s eyes involuntarily jerk or move rapidly. While this does occur naturally outside of intoxication, alcohol can exaggerate jerking and rapid eye movement. In this test, an officer will require the driver to follow an object, such as a pen, from side-to-side. If extensive jerking is present or the driver cannot smoothly follow with their eyes, it is more likely that their BAC is higher than the legal limit of .08%.

Walk-And-Turn Test

In walk-and-turn tests, officers require the driver to walk heel-to-toe and take nine steps in a straight line. After this, they must turn around and take another nine steps. While the driver completes this, the officer will monitor for signs of intoxication, such as lack of balance, inability to turn, using arms to balance, or failing to take nine steps. If two or more indicators are present, the driver may fail the test.

One-Leg Stand Test

During one-leg stand tests, the driver must stand with one foot off the ground and count down until the officer allows them to release. Over a period of 30 seconds, the officer will monitor for different indicators of impairment. Specifically– hopping to maintain balance, placing their foot on the ground, and swaying or using arms to balance. When two or more indicators are present, it is typically a sign of intoxication.

When These Tests Are Inaccurate

Oftentimes, field sobriety tests are given too much weight when making an arrest for DWI. These tests often produce inaccurate results. Why is this the case? There are several factors that may lead to one’s inability to successfully pass field sobriety tests, even when sober.

  • Inconsistent or poor instructions.
  • Lack of coordination or general balance.
  • A variety of medical conditions, such as joint or mobility issues.
  • Fatigue or a lack of sleep causes physical symptoms that imitate intoxication.
  • Consuming caffeine can impact the nervous system, subsequently playing a role in field sobriety tests.
  • If the road’s surface is rocky, uneven, or even slippery, an individual may not be able to balance or walk in a straight line.
  • Anxiety or nerves can also impact one’s ability to take a field sobriety test and pass. An officer may mistake nervousness for intoxication.

These are not the only factors that may impact an individual when taking field sobriety tests, but compromise some of the most common.

When Results Need Challenging

After experiencing inaccuracies with field sobriety tests, it is paramount to seek out legal representation. The team at Shane Phelps Law understands the importance of reviewing present evidence and can build a strong case for defense. Contact us at any time if you need assistance.