Police officers typically perform a three-part field sobriety test after a traffic stop where there is the suspicion that a motorist may be impaired by alcohol or drugs. While the police refer to the field sobriety protocols as “tests,” it's like doing exercises or acrobatics. Most people can't do them under any conditions.
During these exercises, police officers observe a suspect's balance, physical ability, attention level, along with other factors that the officer may use to determine whether the suspect is driving under the influence. The roadside exercises are commonly called divided attention tests – the officer requires the motorist to do the mental task of following instructions and the physical task of doing the exercises at the same time.
Officers grade the suspect's performance on a field sobriety test to be used as evidence in DUI cases. The purpose of all sobriety tests is to allow a police officer to determine as to whether or not there is probable cause to arrest someone for driving under the influence.
There are only three field sobriety tests endorsed by the National Highway Transportation Safety Administration: (1) horizontal gaze nystagmus; (2) walk and turn; and (3) one-leg stand. Police officers often require motorists to touch their nose with their fingertip or to count out loud. These tests, however, have never been validated and are not part of the approved testing protocol.
Field sobriety testing is designed so that people fail. It is extremely difficult for a sober person under the most ideal circumstances to perform the tests. Yet, field sobriety testing is usually administered on the side of the road, often at night, where there are many distractions like passing cars, steep inclines in the road surface where the tests are performed, and flashing lights from the police vehicle.
Just like when you were in school, there is a grading process. Police officers routinely look for “clues” that have been identified to be associated with impairment. But, just like in school, if the test is not graded properly, it is not a valid test. The same concept applies in field sobriety testing: if the officer failed to grade the test properly, it is invalid. That's why it is so important to hire an attorney who is schooled in the field sobriety testing process and knows how to attack the process when the police make mistakes. Mike Sherman is certified in Standardized Field Sobriety testing – he went through the same certification process that the police go through.
What Is The Officer Looking To Observe In The Horizontal Gaze Nystagmus (HGN) Test?
Police officers use the horizontal gaze nystagmus test, as part of the field sobriety testing process. It is one of three field sobriety tests. Nystagmus is the involuntary jerking of the eyes that can be caused by alcohol impairment. This test is commonly performed by a police officer holding an object, usually a pen or small light, approximately 12 to 15 inches from your nose and then slowly moving it from one side to the other. You follow the object with your eyes while keeping your head still.
There is no scientific validity for the test and the test results are not admissible at trial. The test results can be used only when considering whether there is probable cause to make an arrest. The problem with the test is that sober people have nystagmus. There are over 30 causes of nystagmus unrelated to alcohol impairment. Simply drinking caffeine can cause nystagmus. The HGN test is commonly given in cases involving driving under the influence of drugs but the test has never been scientifically validated for drug cases. None of the standardized field sobriety tests have been validated for drug cases.
What Is The Officer Looking To Observe In The Walk And Turn Test?
The walk and turn test involves the suspect being ordered to take nine heel-to-toe steps along a straight line. After taking nine heel-to-toe steps, the suspect is then directed to turn on one foot and return in the same exact manner (9 heel-to-toe steps) in the opposite direction. Police officers look for one of eight indicators of impairment such as not walking heel-to-toe, stepping off the line, or using arms for balance. If a motorist shows two or more indicators or clues, the police officer will believe the test shows impairment.
Police officers routinely administer the walk and turn test incorrectly and/or interpret the clues improperly. This leads to greater uncertainty surrounding these “tests.” Often, police officers require motorists who are physically unable (even disabled) to actually attempt the tests. We had a case where the officer required our client, who used a walking cane, to attempt the tests.
That's why it's so important to have a lawyer who is certified in this area of law enforcement so that he can see the flaws in the testing process.
For more information on Standardized Field Sobriety Tests In PA, a free initial consultation is your next best step. Get the information and legal answers you are seeking by calling 412-471-5000 today.