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Illinois Driving Under the Influence (DUI) and standardized field sobriety tests

Recently in the news is that former Chicago Blackhawks star Chris Chelios was arrested in Illinois for DUI. As I viewed this online report from the Daily Herald, the following statement from reporter Jim Davis, who had viewed the DUI arrest video caught my eye:

I had heard that the field-sobriety tests are tough to ace, even to someone who might be stone-cold sober. So as Chelios struggled a bit with keeping his arms at his side, balancing on one foot and counting “one one-thousand, two one-thousand …” I was compelled to stand up and try this myself. I didn’t fall, but I wobbled and had to stretch out my arms for balance. And, for the record, I was stone-cold sober at the time.

Most of us have heard of the police asking you to “walk a straight line”. The United States Department of Transportation, National Highway Traffic Safety Administration (NHTSA) has a name for this: Standardized Field Sobriety Test (SFST).

NHTSA defines the SFST as “a battery of three tests administered and evaluated in a standardized manner to obtain validated indicators of impairment and establish probable cause for arrest”. In other words, the officer will ask you to perform three tests, and your performance on those tests will be one of the factors he will use in deciding whether to arrest you for DUI.

The officer will usually capture your performance on the SFST with a video camera situated in his squad car. The three tests are the:

· Horizontal Gaze Nystagmus (HGN)
· Walk-and-Turn (WAT)
· One-Leg Stand (OLS)


The HGN involves your eyes tracking the movement of a small object (an ink pen for instance) that the officer movers across your line of vision. The officer assigns failure “clues” based upon his perception of your performance. Observing you perform this test on video does not provide the viewer with any useful information, in this author’s opinion.

The WAT is essentially “walking a straight line”. Failure on this test is evident when impairment is extreme.

However, in many situations, the police cite hyper-technical grounds for assessing failure clues. The video can in some instances work to your advantage, since the judge or jury can compare the officer’s assessment of your performance against what they see with their own eyes.

The OLS is just what it says: you are asked to stand on one leg and count to thirty. Again, the video may help you. (This is the test Jim Davis unsuccessfully completed)

It is important to remember that all three tests are “standardized”. That means your performance (and your sobriety) is measured against the typical person and how he or she would, if sober, be expected to perform on the tests. If your athleticism is closer to a regular guy such as Jim Davis rather than the professional athlete Chris Chelios, you may not get a fair shake from the police.

This is precisely why our Constitution provides that a jury of your peers, not the police, determines your guilt or innocence. If you simply plead guilty because the police say you are, you give up the chance to explain to the jury that you are more like Jim Davis than Chris Chelios. If you are in need of an Illinois DUI lawyer, please feel free to visit my website.

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