Field Sobriety Tests Criminal & DUI Defense in Colorado

Colorado Field Sobriety Tests

Preliminary Screenings in DUI Cases

An officer must have probable cause to arrest you on suspicion of driving under the influence. Probable cause means that some evidence suggests that you were committing a crime – in this case, a DUI or DWAI. One way the officer can establish cause is by subjecting you to field sobriety tests (FSTs).

FSTs are designed to assess your mental and physical abilities as well as your physiological responses to stimulus – all of which can be affected by the consumption of drugs and/or alcohol. Under Colorado's DUI laws, a person is considered to be driving under the influence or while ability impaired if their normal faculties are substantially or even slightly diminished (CRS § 42-4-1301). Thus, if you are unable to perform well on the FSTs, the officer has cause to believe that you have violated the DUI law and can arrest you.

Below we will discuss a few of the FSTs you may be required to participate in. However, to speak in-depth about your case, please contact our Denver attorney at Jim Medley Defense Lawyer by calling (720) 674-7311 today!

The Standard Field Sobriety Tests

Although several FSTs exist, only three have been standardized by the National Highway Traffic Safety Administration (NHTSA): one-leg stand test, the walk-and-turn test, and the horizontal gaze nystagmus test.

Let us explore each in more detail:

  • One-leg stand test: The one-leg stand test is designed to assess your physical and mental abilities. The officer will request that you initially stand with your feet together and lift one leg off the ground. As you are standing on one leg, you will then be instructed to count backward. The officer will observe you to see if you lose your balance, are unable to maintain the count, or cannot hold your leg up for at least 30 seconds.
  • Walk-and-turn test: With this test, your attention is divided between maintaining motor control and using mental abilities and listening skills. The officer will instruct you to stand with your arms at your side and walk forward in a straight line, ensuring that the heel of your front foot touches the toe of your back foot. They may also ask you to count each of your steps out loud. After you have taken the requisite number of steps, the officer will instruct you to turn on the spot and walk back to the starting point while continuing to count and touch heel to toe. The officer will be watching for any signs of intoxication, such as failure to maintain balance or comply with instructions.
  • Horizontal gaze nystagmus test: Unlike the previously mentioned FSTs, the horizontal gaze nystagmus test is not a divided attention test. Instead, it is administered to assess your physiological responses. The officer will hold a pen, light, their finger, or other small stimuli at eye level in front of you. They will instruct you to follow the object without moving your head. They will then move the object from the left side of your face to the right side. As your eyes move, the officer will be looking for jerking movements in them. These movements are called nystagmus, which can occur when someone is impaired by alcohol and or drugs.

Do You Have to Take Field Sobriety Tests?

At the time of your DUI stop, the officer might use authoritative language to make you feel as if you are required to participate in the FSTs. However, you can politely decline to take them. Doing such will not result in any criminal or administrative penalties.

That said, even though you refuse, that does not mean the officer cannot arrest you. They may use other evidence, such as your behavior, to establish probable cause. Still, if you participate in the FSTs, your performance on them may be used as evidence in your case.

Can FST Results Be Challenged?

The NHSTA may have standardized the three common field sobriety tests, but that does not mean they are infallible.

Several factors can affect a person's performance on them, such as:

  • Medical conditions
  • Environmental conditions
  • Clothing
  • Mobility issues
  • Illnesses
  • Injuries
  • Improper instructions/implementation

Even if you participated in the field sobriety tests, do not lose hope in your case. By thoroughly reviewing the events leading up to your arrest and your specific circumstances, your attorney may uncover ways to challenge the results.

Reach Out to Jim Medley Defense Lawyer for Legal Representation

Attorney Jim Medley is a skilled lawyer with an impressive background in both criminal law and DUI defense. He has trained police officers on testing procedures, has written articles on FSTs, has delivered seminars on field sobriety testing, and holds a master's degree in Forensic Toxicology. We know that a person's ability to perform well on these tests can be impaired by things other than drug or alcohol consumption. That is why we will fully examine your case to determine your options.

Schedule a free consultation with us by calling (720) 674-7311 or submitting an online contact form.

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