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Are Field Sobriety Tests Accurate?

Are Field Sobriety Tests Accurate?

May, 07 2017

You’re probably familiar with the tests that police officers give to people they suspect to be driving while intoxicated. They are called Field Sobriety Tests (FST). The purpose of FSTs is to make the roads safer for everyone. As good as the intentions are, it turns out that the FST is not as reliable as you might hope. This means that you might fail the test and be charged with a DUI even though you are under the legal limit.

How is a Field Sobriety Test Administered?

Officers nationwide use three major FSTs. First is the Horizontal Gaze Nystagmus Test. Nystagmus means involuntary eye movements. The officer asks you to focus on a pen while he moves it from left to right. He’s looking for shakiness or jerky eye movements as you follow the pen. The problem with this test is that many people have nystagmus or shaky eyes for reasons other than alcohol consumption.

The second popular test is the “walk and turn test.” In this test, the officer asks you to walk a straight line, one foot in front of the other, and turn 180 degrees and walk back the same way. This is a combination of a physical test and a cognition test. The officer is checking your balance and how much control you have over your body. It’s not just that, though; he’s also checking to see how well you follow directions. If you count your paces wrong or start before he says to begin, for example, you might fail the test.

Then there’s the “one leg stand test.” It’s strictly a balance test. You don’t have to do a face plant to fail, though; the officer might fail you if you are wobbling, touching the ground with the other foot, or just struggling to maintain your balance. A lot of people don’t have great balance. There is even footage of officers failing the test when demonstrating it to the suspect.

How Accurate Are Field Sobriety Tests?

The fact is that Field Sobriety Tests are not 100% accurate. It isΒ possible that you have a 0.00% blood alcohol level and still fail the FST. What should you do if this happens? You should contest it!

You can challenge the reliability of all three of these FSTs in court, and since they have only an 81-91% reliability rating, you could win.

The result FST mostly depends on the judgment of the officer. If the officer doesn’t perform the test correctly, it could skew the results. Because of this, they have standardized the tests to help ensure that the test isΒ the same for everyone, every time. But it’s not perfect.

Some officers will still use non-standardized tests to determine if a person is intoxicated or not. If the officer asks you to recite the alphabet backward or to touch your nose, that evidence may not be permissible in some courts.

You have a good shot at contesting the results of the FST if you have certain medical conditions. Ear infections, neurological conditions, muscle spasms or an injury like a torn ACL may affect your ability to pass the FST even though it does not impair your ability to drive. If the officer failed to take these things into consideration when giving the FST, it might not be acceptable evidence in your case.

Can I Refuse to Take the Field Sobriety Tests?

You can refuse to take the field sobriety tests and most of the time that’s the best choice. You don’t have much to gain by agreeing to take the FST. The truth is that the officer can arrest you even if you pass the FST if he has other reasons to believe you may be intoxicated. Much of the time, when an officer asks you to take and FST, he already believes that the person you’re drunk. Remember, the purpose of the FST is to collect evidence that can be presented in court if needed.

If you are taken into custody, you will probably be asked to take a breathalyzer or blood test. Don’t refuse a breath or blood test. Depending on the state, the court may suspend your license if you refuse a breath or blood test. You may not get a DUI, but you will be facing a period of license suspension.

What If I Get a DUI?

Getting a DUI is a major problem that can throw a wrench in your life. The consequences are costly both financially and legally. Obviously, the best advice is still, don’t drink and drive. Plan ahead; get a sober ride home. However, if you are facing DUI charges, you want to come out of it without it ruining your future.

The best thing you can do is hire a reputable DUI lawyer. Since DUI cases involve breath samples and blood tests, you’ll want to pick a lawyer familiar with these procedures. Having a lawyer who understands the science of these tests will give you your best chance at challenging the results.

Are Field Sobriety Tests Accurate?
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