Can I Challenge the Results of Field Sobriety Tests in a DWI Case?

During last week’s post in our ongoing series dedicated to understanding each component of DWI law in New Jersey, I referenced the use of the field of sobriety tests to provide proof of intoxication in support of DWI charges. These tests are also used by law enforcement officials to meet the “probable cause” requirement necessary before making an arrest.

First, the officer will generally rely on his or her physical observations of the driver, as well as the conversation with the individual, before asking the person to perform field sobriety tests. For example, if you display bloodshot eyes, have the odor of alcohol on your breath, or admit to drinking before the traffic stop, the officer may develop a suspicion that you are currently over the legal limit (0.08% Blood Alcohol Content – BAC).

If the officer asks you to perform field sobriety tests, these will likely include the Standardized Field Sobriety Tests that have been approved by the National Highway Traffic Safety Administration. The three tests used in a vast majority of DWI cases are: the Horizontal Gaze Nystagmus (“HGN”) Test, the walk and turn test, and the one-leg stand test. Police are trained and certified in conducting these tests; however, they may make errors when giving instructions or evaluating the results. Identifying potential errors in police protocol during these tests can be an effective way to challenge the validity of field sobriety results in court.

Although these tests are considered valid and accurate if administered in accordance with standard procedure, there are a host of intervening factors that may skew the results. For example, prior injuries or conditions such as foot or knee problems may cause balance issues, making the performance of field sobriety tests extremely difficult for an entirely sober driver. Further, there are many roads, weather, and lighting conditions that officer’s simply cannot control which may cause difficulties when attempting to perform a field sobriety test successfully.

Lastly, the Horizontal Gaze Nystagmus (“HGN”) Test has been deemed unreliable by the New Jersey Supreme Court, and thus, the results of this test are inadmissible in court. As you can see, field sobriety testing is far more nuanced and less of a science than some would lead you to believe. This provides us with a myriad of opportunities to undermine the State’s case when you are faced with DWI charges.

To read the instructions and procedures for conducting Standardized Field Sobriety Tests, click here. For additional information and a consultation about your DWI charges, contact the Law Offices of Edward S. Cooper today.