Field Sobriety Tests: Faulty Tests Lead to False DWI Charges

Posted On December 19, 2023 Charles Ramsay

Imagine getting pulled over by a police officer due to a taillight being out, only to be accused of driving under the influence of alcohol or drugs. The officer is patrolling as part of the Towards Zero Deaths (TZD) initiative and is looking to make an arrest for DWI. 

Despite driving safely, the officer tells you that he can smell alcohol on your breath and asks you to step out of the car to perform some tests “to make sure you’re okay to drive. Then we’ll get you on your way.” 

He gives instructions and asks you to perform the one-leg stand, the walk-and-turn test, and the horizontal gaze nystagmus test. These are standardized field sobriety tests (SFSTs) – the core of police procedures to prove driver impairment. 

The problem is these tests are all based on flawed and biased research. And they are designed to make you fail. 

Take the one-leg stand test, for example. It requires you to balance on one leg for 30 seconds. If you sway, use your arms for balance, hop, or put a foot on the ground, the officer records a “clue” of impairment—just two clues equal failure. 

I challenge any of you reading this right now to try it. Few people can stand on one leg for 30 seconds without swaying while holding the other leg straight, keeping your foot parallel to and six inches off the ground! (Note: you get better with practice). 


Here’s the problem with standardized field sobriety tests (SFSTs)—research shows that these tests can produce false positives, wrongfully implicating sober drivers of driving under the influence. 

Each of the tests has its problems. But the biggest problem with all these tests is the high false-positive rate.

Studies favoring SFSTs are usually conducted by researchers paid by the government to validate the tests. However, independent scientists’ evaluations demonstrate how poorly the government studies were conducted. 

For example, one study showed a 26% false positive rate for SFSTs. And a more recent study looking at cannabis and FSTs showed a 50% false positive rate!

The above studies show that a person can fail these tests simply by random chance.


The solution to SFSTs is good old-fashioned police work!

Observe erratic driving. Pullover unsafe drivers. Use dash cams for evidence. Question the driver.


If you get pulled over and an officer asks you to take these pseudoscientific tests, the best thing to do is to refuse politely.

The tests are designed for failure. You won’t gain anything by performing the tests, and you might give the officer a reason to arrest you.


Chuck Ramsay is the only DWI defense lawyer in Minnesota who has been certified by the National Highway Traffic Administration (NHTSA) to administer SFSTs and to train others in SFSTs. 

He knows how to challenge not only the science behind the tests but also how the officers failed to administer the tests properly, rendering them meaningless.  


If this pseudoscientific testing has victimized you, call Ramsay Law. We know the science, and we know the law. We stay updated with the latest research to keep the state in check.

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