Monday, April 16, 2012

Minnesota Field Sobriety Tests (Explained)

The Minnesota Field Sobriety Test are one of the most controversial aspects of any Drunk Driving arrest.  The National Highway Traffic Safety Administration developed a model system and published several training manuals for administering Standardized Field Sobriety Tests.  Essentially, these tests are known as “divided attention tests” to determine whether someone can perform mental and physical multitasking which is deemed a requirement for safe driving.

Generally, a police officer will ask someone suspected of driving while impaired to submit to one or more tests for the purpose of determining whether there is probable cause for a DWI arrest. If the person fails one ore more of the tests often an arrest is made. An individual who refuses to perform a testis usually simply arrested and must later submit to breath, urine or blood test.  (Because these tests will rarely help someone avoid an arrest - because if the cop has it in his mind to arrest you - he's going to arrest you - my suggest is to not do these tests.)

Minnesota Field Sobriety Tests

Horizontal Gaze Nystagmus Test – Nystagmus refers to the jerking of an eyeball as it follows an introduced object. The administering officer observes the angle at which your eye starts to jerk while you keep your head still. A pencil or the officer’s finger, which should be 12-15 inches away from you, may be used as the object to follow with your eyes while your head isn’t moving. It is believed that if the eyeball jerks before 45 degrees, the driver’s BAC is 0.05.

Walk and Turn Test – Because intoxicated drivers find it difficult to perform tasks and listen to instructions simultaneously, this test requires you to do heel-to-toe movements on a dry, hard surface while following the officer’s instructions at the same time. During the test if the officer finds two or more signs (out of a possible 8 the officers are trained to look for) then you’re believed to have over 0.08 BAC level in your system. According to NHTSA, this test is 68% accurate.

One Leg Stand Test – In this test, the officer instructs you to perform a task while demonstrating the instructions to you. The officer also tells you not to start performing the test until you’re told to do so. To start the test, you have to stand with both heels together while your arms are down the sides. You are them asked to stand on one leg of your choice while holding your other foot out front approximately 6 inches off the ground for 30 seconds. If you struggle in this position, the officer assumes that your BAC is over 0.08.  Based on NHTSA study, this test is 65% accurate.

Do Field Sobriety Tests Really Measure Impaired Driving?
That's the real questions - isn't it.  The purpose of these tests is to ensure that police officers use scientifically-backed tests… but just by virtue of the fact that the officer may screw up in administering these tests (I would argue)  makes them faulty and all but worthless 
The truth be told - even when tests are correctly administered, failing the tests doesn’t necessarily indicate a person is guilty of impaired driving. Experienced Minnesota DWI Attorneys know the assumption that a person with no alcohol in his/her system is coordinated enough to pass the tests is faulty. This is because there are several factors that can cause even a sober individual to become uncoordinated which including: illnesses, stress, fear/anxiety, confusion, tiredness, age, weight, etc.

Now What?

An experienced Minnesota Criminal Defense Attorney, who focuses his practice on Drunk Driving defense, can assist you with demonstrating the problems with these test - and (maybe) worked to get the charges against you reduce and/or dismissed. Honestly, if an individuals performance on field sobriety testing is the foundation for a police officer’s determination whether there exists probable cause for an arrest --- then why not make some hay before you're forced to eat an unfounded charge?  Call the Rolloff Law Office to schedule a FREE CONSULTATION, today, by dialing (612) 234-1165.  Hold the government to its burden - it works to help everyone of us.


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