Facing a DUI charge in Fort Collins can be daunting, especially when field sobriety tests are used as evidence against you. However, an experienced Fort Collins DUI lawyer can help challenge these tests on several grounds, potentially weakening the prosecution’s case. Below are some common strategies used by DUI attorneys to contest field sobriety tests effectively.

Understanding Field Sobriety Tests

Field sobriety tests (FSTs) are designed to assess a driver’s impairment through a series of physical and cognitive tasks. The most common tests include the Horizontal Gaze Nystagmus (HGN), Walk and Turn (WAT), and One-Leg Stand (OLS) tests.

Horizontal Gaze Nystagmus (HGN) Test: This test measures the involuntary jerking of the eyes as they follow an object horizontally. It’s one of the most commonly used FSTs because it is believed to be a strong indicator of impairment. However, several factors, such as improper administration, medical conditions like nystagmus or certain medications, and even fatigue, can lead to inaccurate results.

Walk and Turn (WAT) Test: This test requires the driver to walk heel-to-toe along a straight line, turn, and return. Officers look for balance issues, coordination problems, and the ability to follow instructions. Environmental factors like uneven surfaces, poor lighting, or inappropriate footwear can affect performance, making the results unreliable​.

One-Leg Stand (OLS) Test: In this test, the driver stands on one leg while counting aloud. Officers look for signs of swaying, using arms to balance, or hopping. Like the WAT test, environmental conditions, physical limitations, and even stress can impact the test outcome, making it a less reliable indicator of impairment​.

Common Grounds for Challenging FSTs

Officer’s Training and Administration: One of the most effective ways to challenge FSTs is by questioning the officer’s training and the correct administration of the tests. DUI lawyers often scrutinize whether the officer followed the standardized procedures during the test administration. If there were deviations, the reliability of the test results could be questioned. Officers are required to adhere to strict protocols, and any failure in this regard can be used to discredit the test results.​

Environmental Factors: Conditions such as uneven or slippery surfaces, inclement weather, and poor lighting can significantly affect test performance. A DUI lawyer can argue that the environment was not conducive to an accurate assessment of the driver’s sobriety. For example, performing the WAT test on a sloped or uneven road can cause balance issues unrelated to alcohol impairment.​

Medical and Physical Conditions: Individuals with certain medical conditions or physical limitations may perform poorly on FSTs regardless of their sobriety. Issues such as inner ear problems, leg or back injuries, and neurological conditions can all impact balance and coordination. A lawyer can present medical evidence to argue that these factors, rather than intoxication, caused the poor performance on the tests​.

Lack of Probable Cause: Before administering FSTs, an officer must have probable cause to believe that the driver is impaired. If the initial stop was not justified, or if the officer did not have sufficient reason to suspect DUI, a lawyer can challenge the legality of the stop itself. This could lead to excluding any evidence gathered during the stop, including FST results​.

Subjectivity of the Tests: FSTs are inherently subjective, relying on the officer’s interpretation of the driver’s performance. Different officers may have different thresholds for what they consider signs of impairment, which can lead to inconsistencies. An attorney can argue that the subjective nature of these tests, combined with the potential for bias, makes them unreliable.

The Role of Expert Witnesses

An experienced DUI attorney may also employ expert witnesses to challenge the validity of FSTs. These experts can testify to the scientific limitations of FSTs, the impact of medical conditions, and other factors that could lead to false positives. Their testimony can be crucial in casting doubt on the reliability of the tests during court proceedings​.

Refusing Field Sobriety Tests in Colorado

It is also important to note that in Colorado, drivers can refuse to perform field sobriety tests without facing automatic penalties. However, refusing these tests can still have significant implications, such as the officer deciding to arrest you based on other observations or requesting a chemical test (breath or blood) to assess your BAC level. Knowing your rights and the potential consequences of refusal is critical.

Challenging field sobriety tests require a thorough understanding of both the legal and scientific aspects of DUI law. A skilled DUI lawyer in Fort Collins can use a combination of strategies, including questioning the officer’s administration of the tests, highlighting environmental and medical factors, and using expert testimony to build a strong defense. If you are facing a DUI charge, it is essential to consult with a knowledgeable attorney who can guide you through the legal process and work toward the best possible outcome for your case.

Published by: Martin De Juan