Dealing With Field Sobriety Evidence

Nearly all DUI cases tried in court will include some testimony regarding field sobriety testing (hereinafter "FST"). FST’s such as the One Leg Stand, Walk and Turn and Horizontal Gaze Nystagmus (Eye Test) have gained prominence in recent years as seemingly effective, objective, easy to administer methods of determining impairment. Without adequate training, these tests are presented by the prosecution in court, with one goal in mind. To obtain a conviction! Unless these tests are subject to exacting scrutiny by defense lawyers, a jury may be swayed by their "objective and scientific" nature. Indeed, at first glance, the FST’s seem simple enough for some sober people to perform. It is a defense lawyers duty to demonstrate that these initial observations are not always as conclusive as one might think. The single best way to call these evaluations into doubt is by knowing how these FST’s work and through a thorough and well prepared cross examination. George Stein is trained and certified in field sobriety testing. He is a frequent lecturer on the subject. His advanced training gives him the advantage when it comes to cross examining the arresting officer at trial.

Brief History Of Field Sobriety Testing

In June, 1977, Southern California Research Institute began research for the National Highway Traffic Safety Association("NHTSA") to evaluate the physical coordination tests currently being used at the time to determine their relationship to intoxication and to develop and standardize tests that would provide more reliable evidence of impairment. They used 238 volunteers, who were subjected to each of the following tests: One-leg stand; Finger-to-Nose; Finger Count; Walk-and-Turn; Tracing (a paper and pencil exercise) and alcohol gaze nystagmus. This study was the first significant assessment of the workability of the tests under actual enforcement conditions. Further, this study was the first that standardized objective clues and scoring criteria were defined for the tests thereby validating standardized field sobriety testing. After many years of research and in an effort to standardize FST’s, the NHTSA has adopted three Field Sobriety evaluations for use by police officers nation wide:
1) The One Leg Stand;
2) the Walk & Turn; and
3) the Horizontal Gaze Nystagmus.
In implementing these standardized evaluations, NHTSA has promulgated exacting standards by which the evaluations must be administered; this to ensure their reliability and validity. These standards are published in a manual given to every officer who is NHTSA trained. This manual provides the precise procedures by which police officers are to administer the NHTSA approved FST’s to DUI suspects. More importantly, the precise methodology laid out by NHTSA for the administration of FST’s provides a long overdue objective standard to which the arresting officer can be held.

Police Training

In Georgia, all police officers are supposed to be trained pursuant to the standards promulgated by the Peace Officer Standards and Training Council (P.O.S.T.) and most are. As of October 1, 1995, P.O.S.T. adopted the three NHTSA approved FST’s and the corresponding standards for the administration thereof. While this NHTSA training is mandatory for all new police recruits in Georgia, many veteran officers have not been NHTSA trained. Thus, it is important for lawyers to determine via pretrial discovery whether the arresting officer has had NHTSA training. Cross examination techniques for NHTSA trained officers may be markedly different from those who have not been so trained. Lawyers will be well served on cross examination by holding NHTSA trained officers to the high standards mandated by NHTSA for the administration of FST’s. In contrast, with non NHTSA trained officers, your goal is to show the jury an officer administering complex tests without the training and knowledge to do so properly. But, even where the arresting officer has not been NHTSA trained, every attempt should be made to cross examine as to the NHTSA standards. Your lawyer should ask several questions. Find out what sort of training the officer does have. Who showed him how to administer an FST? What expertise did that instructor have? Why was that particular test employed? What assurances does the officer have that the test is accurate?. Surely a lack of adequate training in administering tests the state holds out to be scientific and objective should not be a shield behind which the untrained officer can hide while others in the same precinct are held to a more exacting standard. On first impression, it might seem that to focus extra attention on the state’s scientific evidence would only serve to further damn a person suspected of DUI. But as previously indicated, the procedures mandated by NHTSA for administering the three standard FST’s are exacting and complex. More likely than not, the arresting officer in any particular case will not have performed each test exactly as required by the NHTSA standard in spite of his training. It is in the contrast between the detailed procedures required by NHTSA and the methods actually employed by the arresting officer in administering the FST’s to the DUI suspect that reasonable doubt lies.

Field Sobriety Testing 101

When a well trained DUI lawyer confronts the arresting officer about his administration of the field sobriety tests, he must know more about those tests than the officer does. To achieve this, he must become a student of the science and methodology behind these tests. This requires getting a copy of the NHTSA manual entitled Improved Sobriety Testing (DOT HS-806-512) and learning it. This manual can be obtained from NHTSA at, Administrative Operations Divisions, Room 4423, 400, Seventh Street, S.W. Washington D.C. 20590. The manual is useful in three important respects. First, because NHTSA adopted only the three FST’s it found to be the most reliable after extensive study, the manual will discredit other FST’s, such as the touch your nose test or, say the alphabet. Second, as noted previously, the methodology in the manual provides an objective standard by which to hold the officer administering any NHTSA approved FST. And finally, the NHTSA manual shows that objective scoring of these tests is possible, this despite the fact that most officers grade these tests subjectively. Another pamphlet entitled Guide for Detecting Drunk Drivers at Night DOT HS-805-711 (available at the same address) should also be obtained and if possible, introduced at trial. This pamphlet contains a study conducted by the scientists at NHTSA in which officers were asked to identify impaired subjects by administering the three NHTSA approved field sobriety tests. From this data, the reliability of the three tests was statistically determined. The NHTSA sponsored research indicates that a subject who exhibits two or more pre-established indicia of intoxication on the One Leg Stand has a 65% chance of being impaired. That means 35% of the people who do unsatisfactorily on this test are not intoxicated. The goal for defense counsel is to put your client squarely in that 35%. The NHTSA research conducted with the Walk and Turn shows that if a suspect exhibits two or more pre-established indicia of intoxication, there is a 68% chance they are impaired. Again, that leaves a substantial 32% of people who performed poorly on this test, despite being stone cold sober. If a subject exhibits four or more indicia of intoxication during the HGN, the odds are such that there is a 77% that the suspect is impaired. That leaves 23% of the people tested who came up a false positive for impairment. You want to give the jury sufficient reason to think that your client could very well have been one of those false positives. Providing the jury with this statistical information can go a long way toward planting the seed of doubt in their mind.

The National Highway Traffic Safety Administration’s Field Sobriety Tests

For each of the standard NHTSA tests, a good DUI lawyer will want to address point by point, the inadequacies of the officers instructions, demonstration, administration and scoring. Each test will be discussed below.

The One Leg Stand

Proper Administration

The one leg stand requires that the officer: tell the subject to stand with feet together, and arms at side; tell the subject not to start the test until instructed to do so; ask the subject if they understand; tell the subject to stand on one foot, with the other foot held straight about six inches off the ground, toes pointed forward and parallel to the ground; demonstrate the stance; tell the subject to count from 1 to 30, by thousands; demonstrate the count, for several seconds; ask the subject whether they understand; if not, re-explain whatever is not understood; tell the subject to begin; allow the subject to resume the test at the point of interruption, should the subject stop or put the foot down, and not require that the count begin again at "one thousand and one".

Standardized Clues

During the test, officers are trained to look for the following validated clues as signs of impairment. Swaying. Putting the foot down. Hopping. Raising the arms from the sides (6 inches or more).

Standardized Scoring

The test is to be scored objectively, giving one point for each indicia of intoxication. Importantly, only one point is to be given per indicia regardless of the number of times that indicia manifests itself. For example, even if a suspect hops four times during the test, his score would only be a one. It is also imperative to recognize that points are only to be given for those indicia specified by NHTSA. Officers are encouraged to make a note of other signs of intoxication, but are only to score the test as to those indicia specified by NHTSA. If a suspect exhibits 2 indicia of intoxication on the One Leg Stand, he fails the test. However, many officers do not employ this objective method of scoring. Instead, if a suspect does not perform up to the officer’s expectations, he is arrested. If the officer in your case graded your client subjectively, George Stein can bring to light the fact that although an objective, nationally approved method for scoring a suspect’s performance on this test is possible, this officer decided that his personal impression of the suspect’s faculties was more reliable. This deviation from the national standards often results in jurors not believing the arresting officer’s version of the facts.

The Walk and Turn Test

Proper Administration

The Walk and Turn test requires that the officer: always begin by having the subject assume the heel-toe stance; verify that the subject understands that the stance is to be maintained while the instructions are given; cease giving instructions if the subject breaks away from the stance, and have the subject resume the stance before continuing; tell the subject that they will be required to take 9 heel-to-toe steps down the line, to turn, and to take 9 heel-to-toe steps up the line; demonstrate several heel-to-toe steps; demonstrate the turn; tell the subject to keep the arms at the sides, to watch the feet, to count the steps aloud, and not stop walking until the test is completed; ask the subject whether they understand; if not, re-explain whatever is not understood; tell the subject to begin; allow the subject to resume from the point of interruption, and not from the beginning, should the subject stagger or stop.

Standardized Clues

The eight validated clues that officers are trained to look for as signs of intoxication are as follows: Loses balance during instructions (breaking away from the heel-toe stance). Starts walking too soon. Stops while walking. Misses heel-to-toe while walking (misses by at least one-half inch). Raises arms (at least six inches or more) from side while walking. Steps off the line. Turns improperly. Takes the wrong number of steps.

Standardized Scoring

A point is to be given for each indicia manifested by the suspect. As with the one leg stand, a score of 2 is unsatisfactory.

The Horizontal Gaze Nystagmus Test

The Horizontal Gaze Nystagmus is essentially a measurement of eye movement. Nystagmus means a jerking of the eye. The perpendicular jerking of the eye measured by this test is measured three different ways. The first is to measure the angle of onset of the nystagmus. By measuring the angle at which the eye begins jerking, an officer can, theoretically, roughly estimate BAC. The second method is to determine whether the nystagmus becomes more "distinct" when the eye is moved to a lateral extreme. The third technique is to look for a lack of "smooth pursuit"; that is, rather than following a moving object smoothly, the eye jumps or tugs.

Proper Administration

To administer the test, the officer is to: hold the stimulus 12-15 inches in front of the subject’s face; keep the tip of the stimulus slightly above the subject’s eyes; always move the stimulus smoothly; always check for all 3 clues in both eyes; check the clues in this sequence-lack of smooth pursuit; distinct nystagmus at maximum deviation; onset of nystagmus prior to 45 degrees; always check for each clue at least twice in each eye.

Standardized Clues

The only clues recognized by NHTSA as valid indicators of horizontal gaze nystagmus are as follows: Lack of smooth pursuit. Distinct nystagmus at maximum deviation. Onset of nystagmus prior to 45 degrees.

Standardized Scoring

A point is to be given for each indicia manifested by the suspect. As there are six clues (three for each eye) of HGN, a score of 4 is unsatisfactory.

The Interested, Imperfect Officer

A well trained DUI lawyer should show the jury from the outset that this officer; even with his shiny badge and blue uniform, has an interest in the outcome of this case and is capable of making mistakes. Right from the start, your lawyer should ask if it is possible that the officer was wrong in his conclusion that his client was impaired. His response should be used against him in closing argument, whatever it is. If he says yes, your lawyer can suggest to the jury that the arresting officer is not even sure the driver was intoxicated. If he says he never makes a mistake, he’s done your work for you. He’s an egomaniac and the jury will know it. Your lawyer should also show the jury that the officer has only told them half the story. This can be accomplished by asking the following questions. First, ask if there is any record of the arrest other than the officer’s report and testimony. Then, go through 20 possible indicia of intoxication. Verify that the officer’s report indicates that the arrested citizen manifested only a few of these conditions. Ask why the officer did not write down that your client did not fumble with wallet and had no trouble getting out of his car or that he was able to converse intelligently without slurring his words or stuttering. Ask why he only wrote down the things he thought the driver did wrong. Show the jury that this officer was more interested in creating a record which would support his decision to arrest than he was in making an accurate record of the events as they transpired. Counsel must show the jury that the FST’s in your particular case, as well as in most cases, are merely administered as a formality and for purposes of gathering corroborating evidence. The officer has almost always already made up his mind that the suspect is under the influence by the time the tests are given.

Your lawyer should also consider requesting copies of the arrest reports of this officer for the month before and after the current arrest. Many officers will invariably testify that the suspects they arrest fumble with their wallet, sway exactly 4 inches and touch down at 19 seconds on the one-leg-stand. If your lawyer can show a pattern of Xeroxed symptoms, he will go far in discrediting the officer.

The Nervous Client

At trial, the officer is likely to state that the driver fumbled with is wallet, slurred his words and seemed nervous or confused. The stress induced by a roadside confrontation with the police is enough to cause even the most well spoken individual stutter and the most coordinated to fumble and falter. It is important to paint an intimidating picture in the jury’s minds. Your attorney should ask the officer if it is normal for people to be nervous when confronted by the police. Another strategic question is to ask a burly officer his height and weight. He should also be asked if he pointed his flashlight in the suspect’s face. It’s critical to get him to admit he is trained to use a forceful tone and demeanor with suspects in order to establish his command over confrontational situations in the field. The officer should be asked if he inquired whether the person stopped had any infirmity, mental or physical, which would preclude him from successfully completing this test. Show the jury the officer did not really care whether the FST’s would be accurate with regard to your client. Showing the jury that the only thing the officer was interested in was gathering incriminating evidence, is a good way to discredit him.

Unnatural Tasks

The prosecution will invariably seek to show that the FST’s requested the arrestee were such that any sober individual could easily perform them. Your counsel must show the opposite. The officer will likely be asked by the prosecutor to demonstrate the ease with which these tests are performed. On cross examination, an experienced DUI lawyer will get the officer to admit that practice makes perfect. The officer should also be asked how many times he has performed these FST’s. This will show the jury that this battery of tests was foreign to the driver.

Poor Instructions

Often the arresting officer will decide a suspect has failed a particular FST due to inadequate performance when in fact is was the failure of the officer to explicitly describe what he wanted the driver to do. If the driver was merely told to tip his head back, hold out his arms out to the side palms up and touch his finger to his nose, he should not fail the test merely because he did not touch the tip of his finger to the tip of his nose. If any portion of his finger touched any part of his nose, he was just doing as he was told, and doing it well. If the officer states the subject swayed while performing the One Leg Stand or any FST for that matter, then he should be asked if he told the driver not to sway. When he says no, it will confirm that the driver was judged on criteria he was not told would be on the test. Last, your lawyer should ask the jurors to try the one leg stand during their deliberations.

Unfavorable Conditions

Perhaps it was a dark and stormy night when the driver was required to perform FST’s on the road side. Perhaps the road was steeply graded or the emergency lane was filled with loose gravel. Maybe the citizen was asked to perform the one leg stand and walk and turn in 5 inch stiletto heels. If the conditions under which the driver was administered these tests were poor, it will usually offend the jury. Once it has been established that conditions for FST administration were not ideal, ask the officer should be asked if he considered giving the driver the test battery in the dry, warm, level, and well lit conditions of the police station. This will show the jury that the officer was holding all the cards in administering these tests and never gave your client a fair shake.


A few closing thoughts. Despite the seemingly objective and scientific nature of the state’s Field Sobriety Tests; and despite the effect that scientific testimony often carries substantial weight with a jury, the credibility of the state’s impairment detection methods can effectively be brought into question. George Stein is trained and certified in Field Sobriety Testing. He often lecutures lawyers on strategic techniques for discrediting officers in this area. His advanced training often convinces jurys to find that FST’s are not fair and merely a tool for police to make Georgia citizens look bad.