If you’ve been pulled over and a police officer suspects that you were driving under the influence, it is likely that you will be asked to take at least one field sobriety test. These tests are designed to evaluate your physical reactions to certain tasks to determine if you are under the influence of drugs or alcohol. However, if you are injured or previously sustained a serious injury, your performance on field sobriety tests could certainly be impacted and may put you at risk to appear impaired.

Standardized Field Sobriety Tests

The types of field sobriety tests you could face can vary, but there are three standardized tests that have been studied by the National Highway Traffic Safety Administration (NHTSA) and have been proven to be consistently effective in identifying impairment. The three tests make up what NHTSA calls the Standardized Field Sobriety Test Battery and have been found to be up to 94 percent effective in determining if a driver’s blood-alcohol level is above 0.08 percent when all three are performed. The three tests making up the Standardized Field Sobriety Test Battery are the Horizontal Gaze Nystagmus, The One Leg Stand and the Walk and Turn. If you are asked to take a field sobriety test you should expect to be subjected to at least one of these standardized tests.

Horizontal Gaze Nystagmus Test

The Horizontal Gaze Nystagmus test might not sound like a familiar field sobriety test, but the procedure is instantly recognizable. Horizontal gaze nystagmus is the natural, involuntary jerking of the eyes as they move side to side. In order to conduct this test, the officer stands in front of the driver and asks the driver to follow a pen or a light that moves side to side in front of the driver’s face.

By observing the involuntary movements of the driver’s eyes, the officer is then supposedly able to tell if a driver is intoxicated. The test has been found to be 88 percent accurate. However, nystagmus testing is also conducted to determine if a person has sustained a concussion- which means that a present or past head injury could create the possibility of a false positive on a field sobriety test.

The Walk and Turn Test

The Walk and Turn test is another iconic field sobriety test. In this test, a driver is asked to take nine steps in a straight line in a heel-to-toe fashion then pivot and take nine heel-to-toe steps in the opposite direction. The officer observes both whether the driver is able to follow the instructions given and whether the driver is able to maintain balance while performing the test. The test has been found to be 79 percent accurate. Once again, a present or past head injury could impact a driver’s ability to concentrate on the officer’s instructions and could impact the driver’s balance. Additionally, any kind of lower body injury could make walking in a straight line using unnatural heel-to-toe steps difficult for a driver to achieve without having trouble with balance.

The One Leg Stand Test

The One Leg Stand test requires a driver to stand on one leg with the other leg six inches off the ground while counting by thousands. The test lasts 30 seconds and the officer observes the driver’s balance to determine any possible impairment due to alcohol. The test has been found to be 83 percent accurate. Most people have tried this test on their own at one time or another and have found that it can be difficult to keep balance for 30 seconds even while perfectly sober. Maintaining balance on one foot requires input from the entire body, so any type of physical injury makes an already trying test even more difficult to pass.

What To Do If You Have a Physical Injury

If you are asked to take a series of field sobriety tests and you recognize that you have a physical injury that could impact your ability to take the tests successfully, it is important to inform the officer of your injury history before you begin taking any field tests. The officer may insist that you take the tests regardless, but you will have established a reason completely unrelated to intoxication that could affect your performance. If you are charged with a DUI and choose to fight your charges this could be an important factor in your DUI defense.

Contact Fienman Defense Today

Field sobriety tests are an important tool for law enforcement and are used as evidence in the prosecution of DUI cases. However, even the most accurate of field sobriety tests can lead to the incorrect result over 10 percent of the time. If you have a physical injury the chance of an incorrect result in field sobriety tests could soar much higher. So if you are facing a DUI charge that is based in part on a field sobriety test you want an experienced Philadelphia criminal defense attorney to aid in your defense.

Call Philadelphia DUI lawyer Michael Fienman at (215) 839-9529 to see how he can help you obtain the best possible result for your case.

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