Discrepancies in field sobriety test accuracy may lead to false arrests

Field sobriety tests can be helpful tools for law enforcement to stop drunk driving. However, they may also be inaccurate and lead to wrongful arrests.

During the upcoming holiday season, law enforcement in Nevada, as well as across the country, is likely to be stepping up efforts to catch drunk drivers. Local drivers may encounter places along the Las Vegas Strip and throughout the city where officers are conducting field sobriety tests to determine if a person has been driving under the influence.

However, these tests may be far from accurate. It is possible that a person can be arrested for drunk driving after failing a field sobriety test, despite not having had anything to drink.

What should I expect from a field sobriety test?

A standard field sobriety test consists of several small tests to screen for signs of drunk driving, states the National Highway Traffic Safety Administration. These tests include the following:

  • The walk-and-turn – During this test, subjects must walk in a straight line, then turn around and walk back without using the arms for balance or swerving out of line.
  • The one-leg stand – Drivers are required to stand on one foot while counting during this test. Losing one’s balance, swaying, hopping or putting the foot down may result in a fail.
  • The horizontal gaze nystagmus – There are certain involuntary eye movements that may signal intoxication. An officer will use a flashlight to look into the subject’s eyes during this test.

Numerous other factors may be weighed during a field sobriety test, such as the driver’s behavior, speech and ability to understand and follow directions. Unlike a chemical test, the field sobriety test relies on an officer’s own interpretation and opinion on whether a person is exhibiting signs of drunkenness.

How accurate are field sobriety tests?

According to NBC 29 News, in one study the results of field sobriety tests were surprisingly inaccurate. Reportedly, the horizontal gaze nystagmus test was the most accurate at 77 percent. The walk-and-turn test was 68 percent accurate, and the one-leg stand was only accurate 65 percent of the time.

Can a physical or mental impairment affect my ability to pass the test?

It is possible, states ABC Action News, for a sober person to fail a field sobriety test and end up being falsely charged with a crime. For example, some speech impediments or cognitive conditions might mimic the signs of intoxication. Someone with puffy or red eyes due to allergies or fatigue might be mistaken as drunk. A person with poor balance or problems walking could have a difficult time passing the one-leg stand and walk-and-turn. It is also possible to fail a field sobriety test for being nervous or not understanding the instructions and performing them wrong. These are only a few of the ways that an officer may wrongly interpret a person’s appearance or behavior as intoxication.

It is important for those facing DUI charges in Las Vegas to have adequate legal representation. An experienced defense attorney may be able to help.