Field Sobriety Tests: Common Mistakes & Challenges

Being pulled over for driving under the influence is severe in Nevada. Following your arrest, you face charges that could lead to fines, jail time, the loss of your driver’s license, the installation of an ignition interlock device in your vehicle, and other penalties if your case leads to a conviction. And if this wasn’t your first DUI, the penalties will be even harsher.

One way police officers will determine whether a driver is impaired is by performing a field sobriety test. If you’re arrested because you failed one of these field sobriety tests, there may be a silver lining — these tests are notoriously subjective and unreliable. If your DUI attorney can prove there were issues with the field sobriety test, it can go a long way toward achieving a favorable outcome in your case.

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Field Sobriety Tests

What Are Field Sobriety Tests?

Field sobriety tests are tests police officers conduct to determine whether a driver is intoxicated. The police use these tests to establish probable cause and justify arresting a driver for DUI, and prosecutors use the results of these tests as evidence when trying to secure a conviction.

Three Field Sobriety Tests

The National Highway Traffic Safety Administration (NHTSA) has made an effort to make the performance of field sobriety tests more objective by officially sanctioning three different tests. In addition, they established guidelines for how to perform the tests and what to look for when determining whether a driver is impaired. The three official field sobriety tests are:

  • Walk and Turn — The driver must walk nine steps heel to toe, execute a turn, and walk nine steps back heel to toe. Problems with balance, failure to maintain heel-to-toe contact, and taking the wrong number of steps are issues that can cause the driver to fail.
  • One-Leg Stand — The driver must balance on one leg while counting “one, one thousand” for 30 seconds. Issues with balance and maintaining numerical order can cause the driver to fail.
  • Horizontal Gaze Nystagmus — The driver must track the movement of the tip of a pen held about six inches from their face. Issues with the eyes failing to follow the movement of the pen smoothly can cause the driver to fail.

Officers must perform all three of these tests. If you fail any of the tests, the officer will likely administer a breathalyzer test, which is against Nevada law to refuse.

Why Use Field Sobriety Over Breathalyzer?

While it may seem like the breathalyzer test would provide sufficient evidence of impairment on its own, police use field sobriety tests because they believe they provide more evidence to establish probable cause for an arrest. If a breathalyzer test is performed incorrectly or doesn’t yield the result the officer is looking for, it substantially weakens their case.

Another problem with breathalyzer tests is that they only measure alcohol-related impairment. The police would not be able to detect the impairment of a driver under the influence of prescription drugs, marijuana, or other substances with a breathalyzer test alone.

What Are Some Possible Mistakes with Field Sobriety Tests?

Officers must abide by strict procedures when conducting field sobriety tests. Even a slight deviation from these procedures can lead to results that culminate in your arrest for DUI. On the bright side, these deviations may also be sufficient to force the suppression of the field sobriety test results — but you need an experienced DUI attorney to make the argument on your behalf.

Some of the ways an officer can err in the administration of a field sobriety test include:

  • Failing to clearly and correctly explain the instructions to the driver
  • Making errors in judgment that lead to an overestimation of the driver’s impairment
  • Requiring the driver to perform the test in a setting that makes the driver more likely to fail
  • Administering the test in inclement weather
  • Failing to ask the driver whether they have medical or other conditions that might affect their ability to successfully pass the test
  • Failing to use their bodycam or tampering with footage

These and other issues with the administration of field sobriety tests can significantly affect the already questionable accuracy and validity of the results.

Challenging the Results of Field Sobriety Tests

As your Las Vegas DUI attorney examines the facts of your case, they’ll look for weaknesses in the prosecution’s charges against you, and the results of field sobriety tests are among the first things they’ll investigate. There are several effective strategies for defending against a DUI charge and calling field sobriety test results into question:

  • General Unreliability — Field sobriety tests are subjective and don’t always prove that a driver was impaired, as evidenced by the fact that a driver can fail the test while entirely sober.
  • Improper Administration — Poor officer training can result in a failing score if the officer’s judgment and understanding of the tests is inaccurate. If they fail to explain the instructions clearly, this can also result in the driver not understanding what to do and failing the test.
  • Improper Setting — Field sobriety tests must be conducted on solid ground flat and free of debris and obstructions. The area must also be well-lit. Improper conditions can make it harder for the driver to perform the test and more challenging for the officer to evaluate the driver’s performance accurately.
  • Medical Condition — Certain medical and physical conditions, such as arthritis, vertigo, joint injuries, or chronic pain, can make it more difficult to pass a field sobriety test even when a driver is sober.

Suppose your attorney can sufficiently demonstrate the invalidity of the field sobriety test results and have them declared inadmissible in court. In that case, this can improve your likelihood of achieving a favorable outcome.

Contact a Las Vegas DUI Attorney Today

If you’ve been arrested for driving under the influence, you need a Las Vegas DUI attorney with experience defending drivers against these serious charges. De Castroverde Law Group Criminal & Immigration has decades of combined experience working with individuals accused of impaired driving and understands the issues that can arise when a case relies on the results of field sobriety tests.

An improper field sobriety test can devastate your personal and professional life. De Castroverde Law Group Criminal & Immigration will aggressively defend you against DUI charges and seek the most favorable outcome possible in your case. Contact us today to learn more about how we can help you fight for your rights and your freedom.