Field Sobriety Tests (FSTs) are the roadside examinations administered by the police officer in investigating whether you were operating your vehicle under the influence of alcohol. Field sobriety tests are standardized tests and were developed and sponsored by the National Highway Traffic Safety Administration (NHTSA). The standardized field sobriety tests, if given in a prescribed manner, under a standardized setting, supposedly demonstrate validated indicators or cues of a person's impairment. When the tests are administered in the manner detailed by the NHTSA and an officer observes these cues, it allows him to establish probable cause to believe an operator is impaired and arrest that person for OUI. Many times the FSTs are administered incorrectly, in an inappropriate setting or to an inappropriate candidate. Even if administered correctly, according to the NHTSA, there are large degrees of unreliability applicable to these tests, as much as 35%. The three primary standardized field sobriety tests are:
Horizontal Gaze NystagmusIn the performance of this test, an officer asks a suspect to following a pen or small flashlight, tracking left to right with his eyes. A person's eyeball jerking (nystagmus) is magnified by the amount of impairment due to alcohol. There are, however a large number of causes of nystagmus other than alcohol. This test is regularly deemed inadmissible in Massachusetts. Despite its non-evidentiary use, police officers conducting tests roadside regularly utilize this test in the formation of probable cause to place a suspect under arrest for OUI. Nine-Step Walk and TurnThe nine-step walk and turn test is a divided attention examination. One part of the test is the cognitive phase. The officer is conducting observations of the operator's ability to understand and follow instructions during the course of this phase of the test. During this time, the officer is verbally instructing and physically demonstrating how he wishes this test to be performed. The operator is advised to stand still, feet together, hands at his side during the performance of the instruction phase. He is also instructed not to start the test until all of the instruction and demonstration is complete. The officer will typically make and record observations of an operator during this phase. The second phase is the performance of the test. What is required in the physical performance of the test is that the subject walk on a straight line, one foot in front of the other, touching heel to toe, keeping his arms to his side, counting the steps out loud. The subject is required to take nine steps out, articulate a turn at the end and take nine steps back in the same manner. During the performance of this test, the officer is watching for eight cues of impairment:
If a suspect demonstrates two of these eight cues at any time during the performance of this test, the subject is deemed to have failed this test. This test supposedly demonstrates a 68 percent reliability that the subject is under the influence of alcohol and has a BAC of .10 (now .08) or more. One Leg Stand TestLike the nine-step walk and turn test, the one leg stand test also is a divided attention test, cognitive and performance. During the instruction stage, the suspect is required to stand with his feet together and his arms at his side. The officer should verbally instruct and demonstrate the performance of this test for the subject. The performance stage of this test requires that the subject stands with one foot of their choice approximately 6 inches off the ground, straight out in front of them and counts out loud by thousands for 30 seconds. The suspect is advised not to hop on the one foot or to use his arms for balance. During this test, the officer is trained to observe for four cues of impairment:
If an officer observes two or more of the above cues, this test supposedly demonstrates a 65 percent reliability that the subject has a blood alcohol content of .10 (now .08) or more. ConditionsThere are certain conditions, under which the tests should be administered, as required by the NHTSA. The tests are to be administered on a hard, dry, clean, non-slippery, level surface in a well-lighted area. Tests that are administered in less than standardized conditions diminish the already marginal results, which an officer might obtain. The tests that are mentioned above are the only tests that are validated for use by an officer in detecting intoxication in an operator. Oftentimes you will see or hear about tests such as touching finger to nose, picking up coins, and counting backwards being utilized by officers as field sobriety tests. There is no scientific validation for these tests and they offer little or no documented reliability for the officer to accurately detect impairment. Remember, if any element of the standardized field sobriety test is altered or compromised, then the validity and reliability of the test is compromised. These compromises work in your favor in court. Can I refuse the Tests?In Massachusetts, an operator has a right to refuse to perform field sobriety tests. By performing field sobriety tests, you are only providing evidence to the officer in forming his OUI case against you. Many officers don't understand the FST's criteria or remember them from the police academy. Oftentimes it appears that the operator was already going to be arrested before the tests, and they were administered so the officer could record some observations for his report. An operator is advised to exercise their right to refuse the performance of field sobriety tests. In the typical administration of field sobriety tests, a police officer will not describe to the subject the criteria he is looking for in the performance of this test. The officer typically will not describe to the subject the various cues he is looking for. The officer typically will not describe the number of cues necessary to formulate the failure of the test by the operator. In a typical stop, the officer will ask the operator to perform several field sobriety tests. At the conclusion of those tests, the officer will inform the operator that he is placing the subject under arrest. Prior to advising the operator they are under arrest, the officer will have virtually no discussion with the operator about the performance of the tests. It is not uncommon to have persons arrested for OUI to state that they did well on the FSTs only to see a completely different description of their performance as described by the officer in his arrest report. Remember, everything you say and everything you do can and will be used against you in a court of law. Be smart and protect yourself. DisclaimerThis article is intended as an overview of basic field sobriety tests administered by local police departments as instructed by the NHTSA. The foregoing is provided for information purposes only. For a more encompassing discussion of field sobriety testing, you should consult in person with a qualified criminal defense lawyer. |
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