Challenging Field Sobriety Testing in Colorado

by John Buckley on Feb. 26, 2020

Criminal DUI-DWI Criminal 

Summary: There are many ways that a Colorado DUI attorney can challenge the results of field sobriety testing.

Do I have to perform these field sobriety tests?

Absolutely not! Nor should you. These "tests" are designed for failure. They are an abnormal test used to decide if you are normal. Studies have shown that officers will arrest one out of five sober people based on their performance. Officers SHOULD explain that these SFST's are VOLUNTARY. You should politely decline.

Horizontal Gaze Nystagmus or HGN

Prosecutors will characterize this as "the eyes never lie!" This assertion would be laughable if the consequences weren't so serious. Nystagmus is the involuntary jerking of the eyes. If you ask someone to spin around quickly a few times and then stop, you will notice this phenomenon by casually looking at their eyes.

The amount of instruction officers receive in this highly dubious test is about 2-3 hours. After this training, they then suggest UNDER OATH that they can distinguish between the nystagmus caused by alcohol ingestion from nystagmus caused by dozens of other circumstances. Trained physicians who look at eyes every day won't make this claim.

Additionally, if the officer performs the test incorrectly, they will induce the very finding that they claim resulted from alcohol.

Walk and Turn

If an officer were on patrol and noticed someone walking heel to toe along a straight line while keeping their hands at their sides and looking at their feet, the officer would stop and find out if this person was crazy. Yet this very test is used to decide if a motorist is under the influence. There are 8 possible ways for an officer to count off on this test. If you miss two, you fail. The overwhelming majority of the time, you won't be told what the grading criteria is.

Your DUI defense attorney needs to be familiar with these tests and be prepared to aggressively cross examine the arresting officer.

One Leg Stand

Here again, the officer will ask the motorist to perform an abnormal test to decide if you are "normal." Any loss of balance on your part will likely be graded as a failure. Many very sober people cannot stand on one leg, perfectly balanced, for 30 seconds.

Hire an attorney who has been trained to perform Field Sobriety Tests

In order to effectively challenge the results of the field sobriety testing, your attorney should be more familiar with the tests than the officer. Ask your attorney if they are certified in Standardized Field Sobriety Testing when you interview them.


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