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What are DUI field sobriety tests? 

Most of us have seen police officers on television administering field sobriety tests on the roadside – one that is commonly shown on TV involves tilting your head back, closing your eyes, and touching your nose. 

But did you know that the “touch your nose” test is not a standardized field sobriety test approved by the National Highway Traffic Safety Administration (NHTSA), and there are only three “standardized” field sobriety tests that have been shown to have any scientific value? 

In this article, we will cover the basics of DUI field sobriety tests in SC, including:

  • The difference between field sobriety tests and standardized field sobriety tests, 
  • Whether FSTs are reliable and admissible in court, 
  • The three types of standardized tests, and 
  • How to challenge field sobriety test results in court. 

What are Field Sobriety Tests (FSTs)? 

A field sobriety test is a “test” that is given by a police officer on the side of the road that presumably will tell the officer if your blood alcohol content is greater than .08%. 

There are many kinds of roadside “tests” that police have used over the years, but there are only three that are approved by NHTSA as “standardized field sobriety tests.” 

Are You Required to Take SFSTs on the Roadside? 

You are not required to take field sobriety tests on the side of the road. 

Should you? 

If you do, and you are intoxicated, you might provide the officer with evidence they need to convict you of driving under the influence in court. 

If you do, and the officer thinks you are intoxicated, you may still be providing the officer with evidence they need to convict you of DUI

If you do, and you are not an athlete with perfect balance and no medical nystagmus who has practiced field sobriety tests, you may still be providing the officer with evidence they need to convict you of DUI. 

If you don’t, and the officer suspects you are intoxicated, the officer is likely to arrest you anyway – but at least you did not give them evidence to use against you in court. 

Are Field Sobriety Tests Reliable? 

Despite what police and prosecutors will tell the jurors in your DUI trial, field sobriety tests are not designed to provide reliable evidence of a person’s blood alcohol content (BAC). 

They are designed to give police and prosecutors pseudo-scientific evidence that they can present to a jury to help them get a conviction. What they do not tell you is that field sobriety tests are designed for you to fail

According to NHTSA, the standardized field sobriety tests are approximately 91% accurate if:

  • All three standardized tests are administered, 
  • The officer administers the tests properly (they often don’t), and
  • The subject doesn’t have health problems that would affect the results. 

But how often do police officers administer the tests properly? And how often do police officers administer the tests despite a subject suffering from back problems, knee problems, balance issues like vertigo, foot injuries, medical nystagmus, stiffness from driving long distances, or other medical issues that would affect the results? 

If you perform poorly on a field sobriety test, that could indicate that you are too intoxicated to drive. It could also be caused by literally hundreds of medical issues or your physical condition that have nothing to do with intoxication. 

The Tests are Subjective

How are the tests, despite NHTSA’s studies, designed for you to fail? 

They are subjective

There are a certain number of “clues” for each test, like failing to touch your heel to your toe or swaying as you are standing listening to the instructions, and, if the officer identifies enough “clues,” you fail. 

The bottom line is, if the officer thinks that you are DUI, you will fail their FSTs, and they will use their “test” as evidence against you in court. If the officer doesn’t think that you are DUI, they wouldn’t be giving you the FSTs in the first place. 

How Do You Challenge FST Results in Court? 

How we challenge the FST results depends on the facts of each client’s case and the law as applied to those facts. There are some common scenarios, however, including:

  • If the officer does not administer the test strictly according to NHTSA’s instructions, the test is invalid and 1) the court might agree to exclude the FSTs at your trial, or 2) your attorney can demonstrate on cross-examination why the tests were flawed. 
  • If the officer administered non-standardized FSTs without a good reason, those tests may also be excluded from your trial. 
  • You may have a legitimate medical reason for performing poorly on the SFSTs (which may or may not require expert testimony to establish at your trial). 
  • Your attorney might ask the officer to demonstrate the FSTs for the jurors during your trial, point out that the officer is in top physical shape and practices these tests on a regular basis, and suggest that the jurors attempt to perform these tests themselves during jury deliberations – it is almost guaranteed that there will be one or more jurors who are unable to perform the tests due to health issues. 

What are the Standardized Field Sobriety Tests (SFSTs)? 

There are only three standardized tests that have been approved by NHTSA, including the HGN test, the walk and turn test, and the one-legged stand test. 

Horizontal Gaze Nystagmus (HGN)

The officer will move a pen or small light back and forth in front of your eyes and ask you to follow the pen. The officer is looking for “nystagmus” – an involuntary jerking of the eye that can be caused by many different medical conditions besides intoxication – and will be looking for clues including:

  • Equal pupil size, 
  • Resting nystagmus, and
  • Smooth or equal tracking. 

Is the HGN test reliable? 

In State v. Sullivan, the SC Supreme Court held that, although the HGN test is unreliable, it is circumstantial evidence only, and it cannot establish a subject’s BAC, it is admissible in court if it is offered in conjunction with the other standardized tests. 

Walk and Turn Test

There are two parts to the walk and turn test:

  1. Standing with your feet heel to toe, arms at your sides, and remaining that way until the officer finishes giving you the instructions, and
  2. Taking nine steps heel-to-toe on a straight line, performing a turn exactly how the officer says to perform it, and then taking nine steps back. 

The “clues” the officer will use to fail you include:

  • Losing your balance, 
  • Starting too soon, 
  • Stopping while walking, 
  • Not touching your heel to your toe on every step, 
  • Stepping off the line, 
  • Using your arms to help balance, 
  • Not making a perfect turn exactly the way the officer said, and
  • Taking the wrong number of steps. 

One-Legged Stand Test

The one-legged stand test also has two parts:

  1. Standing with your feet together and arms at your sides and not moving until the officer finishes giving the instructions, and
  2. Raising one leg with your foot six inches from the ground and with your foot parallel to the ground while keeping your legs straight and your arms at your side and counting “one one thousand two one thousand” until the officer tells you to stop counting. 

Did you fail to keep your foot parallel to the ground? Didn’t keep your foot six inches from the ground? Started before the officer said to start? Stopped counting before the officer told you to stop? Swayed while you were standing straight with your feet together? 

Do you see how the tests are designed for you to fail, and a police officer can – subjectively – make the test results match their suspicions? 

What are the Non-Standardized DUI Field Sobriety Tests? 

There are many non-standardized FSTs that police have used and still use despite their unreliability, including:

  • Feet together, eyes closed, tilt head back, and touch your nose, 
  • The “alphabet test,” requiring you to start with a specific letter and end with a specific letter, or even saying the alphabet backwards, 
  • Counting backwards, 
  • Touching each finger to your thumb as you count, or
  • Patting one hand with the other hand, alternating top and bottom as you count.  

These tests are never a reliable indicator of intoxication, and NHTSA’s guidelines say that officers should not use non-standardized FSTs unless there is a physical condition that makes the SFSTs impractical. 

Questions About Field Sobriety Tests in SC? 

DUI lawyer Kent Collins will investigate your charges, answer your questions, and do everything legally and ethically possible to get your case dismissed, win your case at trial, or find a resolution that is fair and reasonable, including challenging the results of roadside field sobriety tests.

Get in touch with Kent by phone at 803-808-0905 or use this form to reach him online to schedule your in-person consultation.

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