Fear and Field Sobriety

By: Phillip B. Price, Sr.

In almost every DUI case, the prosecution will offer testimony concerning what have become known as “field sobriety tests.” The results of these roadside maneuvers are offered as evidence of alcohol impairment in DUI trials. Many times the “tests” will be preserved on videotape or audio tape and played to the jury (or judge in a non-jury case) during a DUI trial. In many instances, the performance of the individual on the tests as displayed by video or as relayed by verbal evidence is less than perfect. When the judge or jury sees or hears the performance, they might mistakenly conclude that the person on trial, because of the perceived results of these roadside tests, had consumed too much alcohol. The individual on trial would therefore be found guilty at the conclusion of the DUI trial as a result of the interpretation of these roadside maneuvers.

Often individuals, after being arrested for DUI, state that on the night they were arrested, they did not consume too much alcohol to safely drive their vehicle. When asked about their performance on the roadside tests, they state that the reason they performed so poorly was that they were “nervous” due to being questioned by the police. Many times, this state of anxiety is confirmed by comments made by the individuals on either videotape or audio tape made at the scene. They sometimes state that their “knees were shaking” or that their “heart was racing.” The results of the roadside tests then become a mosaic of varying components and the very important question arises; were the mistakes signifying possible impairment due to alcohol consumption or were the mistakes merely due to a state of anxiety and being nervous? It is the purpose of this article to discuss this concept of “nervousness” and explore from a technical and scientific standpoint, how being nervous and how a state of anxiety might impair one’s ability to perform these “field sobriety tests,” thereby leading to a false interpretation of intoxication.

First, let us briefly look at the tests citizens are subjected to in a typical DUI investigation at roadside. In a typical roadside encounter where an individual is suspected of drinking and driving, they are directed to perform several different maneuvers. These maneuvers can be divided into two types of tests. The tests are either categorized as being “standardized” or “non-standardized” field sobriety tests. The standardized tests consist of 1) the walk and turn test, 2) the one-leg stand test, and 3) the horizontal gaze nystagmus test. They are called standardized tests because the National Highway Traffic Administration commissioned the Southern California Research Institute to study and make recommendations for field sobriety tests to be used by police officers.(1) After studying several different ones, they recommended the above three tests along with a standardized procedure for the administration of each test. Non-standardized tests that are sometimes offered to individuals suspected of drinking and driving are the Alphabet test, the finger count test, the finger-to-nose test, and the count down test.

While there may be some slight variation in the instructions given by the police in giving the non-standardized field sobriety tests, there should be no variation in the way the standardized field sobriety tests are given. The reason they are called standardized tests is because they should be given in a standardized way each time. Typical instructions given by the police on the various tests are as follows:

1. Walk and Turn

A. Instructional Phase

Stand with your left foot on the line with your right foot in front of the left foot in a heel to toe position. Keep your hands down to your side and maintain that position while I give you further instructions. Do you understand?

B. Walking Phase

Walk heel to toe for nine steps, hands to your side, look at your feet as you walk, count out loud one through nine on each step, with your first step from the heel to toe position being counted as your first step; When you get to nine, leave your lead foot on the line, this should be your left foot; pivot, turning around using a series of small steps, coming back into a heel to toe position. Come back down the line taking nine steps heel to toe, hands to side, counting out loud on each step.

All steps should be on the line and in a straight line. Once you start, do not stop until the test is completed. (Officer should also demonstrate the test).

2. One Leg Stand

A. Instructional Phase

Stand with your feet together and your arms to your side. Do not start this test until I tell you to begin. Do you understand my instructions so far?

B. Balancing and Counting Phase

Stand on either foot, hold the other foot six to eight inches off the ground, toe pointed so that foot is parallel to the ground, keep your hands to your side, look down at your foot, count 1001, 1002, 1003 until I tell you to stop. Do you understand? (Officer should demonstrate).

3. Alphabet Test

Recite the alphabet, beginning with the letter “E” as in Edward and stopping with the letter “P” as in Paul.

4. Finger Count

Touch the tip of your thumb to the tip of each finger, counting out loud, one, two, three, four and come back, four three, two, one. Do it twice.

5. Finger-to-Nose

Stand with your feet together, head back, eyes closed, arms straight out at shoulder level, with your index finger pointed out. Bring your arm, the particular one I tell you to, around in front of you, point it straight out, roll your palm over, come in and touch the tip of your finger to the tip of your nose. Then return your arm back out to your side.

6. Count Down Test

Count out loud backwards, starting with the number 68 and ending with the number 53.

Considering then that at least some of the above tasks are offered by the police to an individual at roadside, what mental and physical skills are called upon in order for the individual to “pass” the tests? Clearly one’s ability to listen intently to very detailed instructions, process and relay back to the police the requested information is an important component. Also, the use of fine motor skills is a primary function required in almost all of the tests. If the fine motor skills fall short of perfection, then the individual goes to jail. Cognitive thinking and recitation are necessary for satisfactory performance to the police and even very small mistakes, such as skipping one letter when asked to recite the alphabet or touching the bridge of the nose instead of touching the very tip of the nose can lead to jail. In the physical portions of the field sobriety tests (FSTs), the accused person is called upon to use fine motor skills combined with cognitive processing. For example, when law enforcement officers assess one’s performance on the walk-and-turn test, small mistakes, such as doing the turn improperly and stepping off the line once can lead to enough so called “clues” of intoxication to cause the person to be arrested. Not being able to stand on one foot for an entire 30 seconds on the one-leg-stand test is sufficient cause for arrest. Far too often, there are very subtle differences between a perfect performance and a “failed” performance, according to the subjective grading system used by the police. The decision to arrest is left to the arbitrary and capricious thought processes of the police officer.

From time to time, the very mechanisms that nature gave us to use in times of “emergency” produce negative instead of positive results in the roadside encounter. For example, imagine that you are driving down the road and there, standing in the middle of the road, is a squirrel. The squirrel just stands there as if it is oblivious to its surroundings. Seconds go by and the squirrel, which is looking right at you, seems doomed to an untimely death underneath the tires of your vehicle. Then at the last fraction of a second, the squirrel darts to one side and narrowly escapes being the day’s “road kill.” Why didn’t the squirrel immediately dart to one side or the other instead of sitting there, aware of the impending danger, using up invaluable seconds? It seems that the squirrel’s “fight or flight” reflexes that are designed to help it in times of emergency sometimes, in fact, lead to an adverse result. As it turns out, when the squirrel senses the impending danger, it is flooded with fight or flight impulses, but the squirrel’s brain cannot assimilate the impulses efficiently enough to react to it immediately. It cannot make the decision whether to go right or left to get out of the way of the approaching vehicle.

Many individuals who have been pulled over by the police, whether they have been drinking or not, will, as a natural and involuntary response to the situation, become scared and extremely nervous. Just like the squirrel in the middle of the road, involuntary responses and defense mechanisms begin to erupt in the individual. What happens when humans become nervous or afraid? The fight or flight involuntary responses kick in. What are these fight or flight responses and what effect do they have on individuals’ abilities to do law enforcement’s field sobriety tests? Common sense alone dictates that being nervous will indeed affect one’s ability to perform certain tasks. In today’s society, the social stigma associated with a DUI conviction is a real concern to most people. The possibility of being arrested, strip-searched, spending time in jail and possibly losing one’s job raises the fear aspect of a typical roadside encounter. Individuals who are pulled over know that they are being investigated for the possible commission of a rather serious crime with mandatory loss of driving privileges, and the experience can be one of grave anxiety, stress and tension. Most people realize that their future lies in the subjective assessment of the police officer. These roadside maneuvers consist of mental exercises combined with physical exercises and are designed for failure due to the scoring system used by the police. The difficulty of the tests, combined with the fear of being arrested creates real fear, especially when the atmosphere of darkness and flashing police strobe lights come into play.

Anxiety, as a byproduct of stress, is one of the most fundamental emotions shared by all species of animals. Stress is a natural response of the body to potentially threatening situations. Obviously, the level of stress and/or anxiety that one would feel in a given situation would vary from individual to individual. Anxiety is a normal reaction to threatening situations and is a part of the ”fight or flight” response system. This is the same “fight or flight” system that caused our ancestors to flee potentially threatening animals or to seek shelter during a storm. The fight or flight response is triggered so that we are prepared to react and protect ourselves. Without anxiety and its physiological manifestations, such as hypersensitivity to environment and enhanced blood supply to leg muscles, the likelihood of harm or disaster in threatening situations would dramatically increase.(2) These fight or flight responses happen automatically and are involuntary in nature.

Anxiety is a psychological response to stressors that have both physiological and psychological components. The threat perceived by a person does not have to be just physical. It can be psychological as well, such as a threat to self-esteem, self-image or identity.(3) Certainly the fear of losing one’s way of making a living by not having a driver’s license as a result of a DUI arrest would be psychologically devastating. The level of anxiety engendered and its manifestations depend on the individual’s maturity, understanding of need, level of self-esteem, and coping mechanisms.(4) When our bodies experience stress, we prepare not only to fight, but also to prevent injury and to heal injury if one occurs. The fight or flight reaction can occur even in the absence of a real danger, and when this occurs it is sometimes referred to as a panic attack.(5) Whether real or perceived, the body gets “geared up.” To prepare itself, a portion of the brain called the hypothalamus activates the pituitary gland (in the brain) which releases ACTH (adrenocorticotrophic hormone). The ACTH then activates the adrenal glands (above the kidneys) which in turn releases two types of chemicals. The first type is catecholamines, especially epinephrine and norepinephrine. These chemicals have the effect of making the body more aroused and ready for immediate reaction. Epinephrine is the substance that is commonly referred to as adrenaline. The second type of chemical, glucocorticoids, are released to help in the event of an injury, i. e. to reduce swelling.(6)

The hormones which are released by the body have a beneficial effect if one were about to engage in a fight or be in a situation where one is required to try to lift a car off of someone, however they have a very negative effect on one’s ability to do field sobriety tests. While increasing the body’s gross motor skills, adrenaline decreases the fine motor skills required to do the type of tests offered at roadside in a DUI investigation. Fight or flight reflexes manifest themselves in effects such as periods of superhuman strength (followed by a precipitous drop), imperviousness to pain, increased speed, gross decrease in fine motor skills, and trembling in the extremities. Strength goes way up, dexterity goes way down.(7)

What at first seems to be a simple reaction is actually quite technical. The hormones secreted when anxiety sets in increase the availability of the body’s energy by glycogenolysis in the liver and in skeletal muscles thus raising the blood glucose and lactate, lipolysis in adipose tissue, mobilization of free fatty acids, and by increasing temperature. (It should be noted that an increased body temperature will adversely affect a breath alcohol analysis to a falsely elevated level).(8) Both epinephrine and norepinephrine also dilate coronary blood vessels. As a consequence, the rate and strength of the heartbeat increases to supply more oxygen to the tissues. This would certainly explain the fact that the DUI-accused made the statement about his or her heart “racing.” While norepinephrine produces vasoconstriction in skin, mucosa, skeletal muscles and most other organs (this would explain “dry mouth” which is another side effect and may be a reason for a “slight slur”), epinephrine dilates veins in skeletal muscles. These effects result in hypertension and consequently in reflex bradycardia. Breathlessness, dizziness and pain or tightness in the chest may be experienced. The pupils of the eye dilate to admit more light and increase peripheral vision to scan for danger. Quite often, police officers state in DUI arrest reports that the subject’s eyes were glassy, bloodshot and dilated. Sensitivity to bright light and visual disturbances may occur. This is material because, more often than not, the tests at roadside are given in the presence of flashing police strobe lights. The digestive system shuts down to conserve blood for the muscles. The shutting down of the digestive system would certainly slow the rate of absorption of alcohol into the blood. Muscles tense to prepare for flight, but may cause spasms and trembling when no action is taken. It is a common occurrence that the person being tested at roadside states that his “knees are shaking.” These complex responses have developed through the evolutionary process and are often seen in individuals who are diagnosed as having “panic attacks.” (9)

Adrenaline is a natural stimulant made in the adrenal gland of the kidney. Its biological name, as stated above, is epinephrine, from the Greek word, nephros, for kidney. Adrenaline is carried in the bloodstream and affects the autonomous nervous system. The autonomous nervous system has two divisions: parasympathetic and sympathetic. Adrenaline affects the fight or flight system, which is also referred to as the sympathetic division of the autonomous nervous system. The sympathetic division controls such things as excitement, emergency and embarrassment. (10) The adrenal medulla is the only source in the human body where production of more than trivial amounts of adrenaline occurs. It is interesting to note that when adrenaline is formed, a “methyl group” is attached to its molecular structure. (11) This is significant because many States use infrared breath testing devices as their official method of breath testing for blood alcohol. Many of these devices use infrared absorption around the 3.5micron wavelength. (Intoxilyzer Model 5000, Datamaster.) Devices using this 3.5micron wavelength will absorb any compound found in human breath which has this “methyl group” in it. This begs the question: will adrenaline production cause an erroneously high breath alcohol result because of the presence of the “methyl group”? Situations such as emotional excitement, fear, apprehension, psychic distress, panic reactions, sexual activity and fight-or-flight stimuli activate many parts of the sympathetic nervous systems, including the adrenal medulla. (11) Even general stress in one’s life often results in increased levels of adrenaline in the body, which may result in physical symptoms such as increased heart rate, etc., and which may remain in the body even after the stress is gone. (11)

A certain level of stress is needed for optimum performance in humans. If you are under too little stress (like the first two days of a week long vacation), then you will find it difficult to motivate yourself. Too little stress expresses itself in feelings of boredom. A slight amount of stress can improve performance in many individuals. It would make them more alert. Different people handle different levels of stress in different ways, and some people just cannot handle even low levels of anxiety very well. Excessive levels of stress or anxiety, however, damage performance.

Much of the research done in the area of anxiety and stress and its effect on the human body have been either in the area of sports psychology or in the area of the psychology of panic disorders. One article on sports psychology and the effects of stress (author unknown) states that excessive levels of stress occur in the following instances:

1. When you think that what is being asked of you is beyond your perceived abilities; and/or

2. When too much is asked of you in too short a space of time.

Many times we hear individuals, when asked to lift one foot and keep it up for thirty seconds, state to the police officer, “I can’t do that!” They know before they start that what is being asked of them is beyond their capabilities. This is clearly a stress “booster” which produces higher levels of adrenaline resulting in decreased fine motor skills, the very skills needed to do the tests satisfactorily. People will also state that they felt like they had done well on the first few tests but that the officer just kept on and kept on till finally they were given one that they could not do. It is true that a lot of different tests are given in a very short time. I would estimate that the average period of time that the roadside testing takes is about six to ten minutes. Normally each test is immediately followed by another test, with no “cooling off” period.

Stress, in these situations negatively affects performance in that:

1. It gets in the way of judgment and fine motor control.

2. It causes the test to become a threat, not a challenge.

3. It damages the positive frame of mind you need for high quality performance by:

a.) Promoting negative thinking

b.) Damaging self-confidence

c.) Narrowing attention

d.) Disrupting flow

4. It consumes mental energy, i.e. worry, and you need this energy to keep technique good.

Very often stress can not only be caused by negative thinking, but it also can result in negative thinking, and in that respect, feeds upon itself. If you interpret a situation saying “I’m in trouble,” then you are much less likely to do well than if you think positively. An interesting study was done to try to determine what causes a person to “choke.” Choke was defined as the inability to perform up to one’s previously exhibited standards. The researchers found that when one mentioned the word “choke” by saying “Don’t choke,” there was a significant decrease in performance of the task (shooting “free throws” was used in the experiment). (12) So, when police officers make comments resulting in negative thought processes of the individual being tested, such as mentioning that if one fails the test(s) the subject is going to be arrested, this could result in the ultimate “choke,” thereby increasing stress levels, increasing productions of adrenaline, and decreasing fine motor skills.

Excessive effort to consciously control movements sometimes interferes with the movement itself. This is sometimes referred to as the “memory drum” theory of neuromotor coordination. (13) For example, if you think too much about the leg movements involved in walking down a flight of stairs, you may well finish up in a heap at the bottom of the stairs. This so-called “deautomatization” could occur in even the most taken-for-granted skill. (14) Simply put, trying too hard can cause a decrease in performance. This is perhaps best exemplified in trying to sink an important putt on the golf course.

Many times the tasks called upon at roadside are being attempted for the first time by individuals. An individual’s perception and cognitive appraisal of a situation is a crucial factor in his/her ability to perform the task. The perceived demands and perceived capabilities to meet those demands are of the utmost importance. The effects of emotion and increased arousal affect the selectivity of attention. (15) When the performer perceives an imbalance between the task demands and his/her capability to match them, anxiety occurs and performance deteriorates rapidly and dramatically. (16) This anxiety disrupts performance by clogging channels with useless information. This high level of arousal can result in an “overflow” to the activation system so that decision-making is by-passed. In other words, in the fight-or-flight mode, the requirement of cognitive thought is taken away. This should cause faster responses which will be beneficial in high stimulus-response compatibility situations or when the skill is well-learned. However, it also carries with it the danger of causing errors through inappropriate responses. This is why coaches state that “athletes should not be asked to do new things at competitions.” (17) This phenomenon would also explain why one would not be able to recite the alphabet without singing them. Adrenaline obviously reduces one’s ability to recite.

In many instances, people are asked to perform these field sobriety tests in front of an “audience”. What effect does an audience have on a person’s behavior and the level of stress or anxiety felt by the individual? First of all, there are potentially three types of audiences in a DUI arrest situation. In virtually all DUI arrests where field sobriety tests are given, there will automatically be at least one audience: the police officer giving the tests. More often than not there is also present at the testing site at least one back-up officer who is also watching the performance of the individual being tested. The third type of audience are citizens who are present, whether it be the persons riding with the accused, or it might be individuals at the arrest location just observing what was going on. Do the presence of these audiences have any effect on the performance of the individual being tested? The notion of objective self-awareness was introduced in 1971 by Wicklund and Duval. This state is one in which the subject’s attention is directed towards the self. When this occurs, he perceives himself as an object. When attention is directed towards the self there will be a comparison of the self with standards of correctness. Wicklund and Duval’s studies with this concept concluded that in situations where an audience is present and one is being asked to do a complex task, the objective self awareness will result in a decrement in performance. (18) When the factor of the audience evaluating the performance is added, performance is worsened to an even greater extent. (19) Under high evaluation situations, more attention would be directed to the self, thereby increasing distraction from the task activity, hence there would be a worsening of performance with high evaluation, with anxiety as the precipitating factor. In DUI roadside encounters, the police audience is clearly evaluating the task performance with freedom as the unfortunate consequence of a poor performance.

There is no doubt that stress, anxiety and/or just being nervous are real contributors to a citizen’s performance of the field sobriety tests being given to him in an attempt to determine his level of alcohol impairment. It remains an impossibility to distinguish, in the practical sense, whether a less-than-perfect performance was due to the presence of alcohol in the person’s system or the result of anxiety or stress on the individual. Maybe the solution to this dilemma might be some method of measuring one’s stress level. While it might be impractical to suggest the Spielberger State-Trait Anxiety Inventory State Scale (STAI) (20), which is used to measure changes in individual’s stress levels, a more practical solution might be to take steps that would lead to the reduction of anxiety in the field sobriety testing venue. A cooling off period, perhaps with casual relaxed conversation might help relieve some of the stress. Multiple testing (giving the same test more than once with at least five minutes in between) would also help give a better indication of the individual’s ability to do the test. I would even suggest that, in situations wherein the individual has been arrested, the person be given another opportunity to be tested at the jail facility wherein the threat of “being” arrested is no longer present. All tests, both at roadside and at the jail facility, should be videotaped.

1. DUI Detection and Standardized Field Sobriety Testing, Student Manual, DOT-HS-178 R6/92

2. Kimmel, Bonnie, Anxiety, Biology 202 Class Notes, 1998 First Web ReportsBryn Mawr College and Howard Hughes Medical Institute, 1998

3. Oberman, Steve, Field Sobriety Tests: View From a Different Perspective, NACDL, Defending With Ingenuity Seminar, Las Vegas, Nevada,1999

4. Medical-Surgical Nursing, 172 (Wilma J. Phipps, PhD, RN, FAAN, et al eds., 5^th ed.1995.

5. Rosenhan DL and Seligman MEP, 1989 Abnormal Psychology (2^nd Edition). W. W. Norton and Co.: New York

6. Carlson, NR, (1992) Foundations of Physiological Psychology. (2^nd Edition). Boston: Allyn and Bacon

7. Casey, Patrick Defensive Use of Firearms, Physio-Psychological effects of Violent Encounters, Ch.V. edited by Massad Ayoob, LFI, 1999

8. IACT (International Association of Chemical Testing ) Newsletter, Volume 9, Number 2, July 1998

9. Barlow DH, Craske MG, (1994) Mastery of your Anxiety and Panic. Graywind Publications: Albany, NY

10. Marieb, Elaine N. R.N., PhD., Human Anatomy and Physiology, 463 (3d ed. 1995).

11. David H. P. Streeten, MB, Dphil, FRCP, FACP, The Autonomic Nervous System, National Dysautonomia Research Foundation

12. Larry M. Leith, Choking in Sports; Are We Our Own Worst Enemies, Int. J. Sport Psychol., 19:59-64, 1988

13. Henry, F. M. & Rogers, D. E. (1988) Increases response latency for complicated movements and a ‘memory drum’ theory of neuromotor reaction. Research Quarterly, 31, 448-458

14. Eysenck, M. W. (1982). Attention and Arousal: Cognition and Performance. Berlin: Springer-Verlag.

15. Easterbrook, J. A. (1959). The effect of emotion on the utilization and the organization of behavior. Psychological Review, 66, 183-201.

16. Jones, J. G., & Hardy, L. (1989). Stress and cognitive functioning in sport. Journal of Sports Sciences, 7, 41-63.

17. Id.

18. Duval, S., & Wicklund, R. A. A Theory of Objective Self Awareness. London: Academic Press, 1972

19. Innes, John M., & Young, Roger F., The Effect of Presence of an Audience, Evaluation Apprehension and Objective Self-Awareness on Learning, Journal of Experimental Social Psychology 11, 35-42 (1975)

20. Spielberger, C., Gorsuch, R. L., Lushen, R., Vagg, P. R. & Jacobs, G. (1983). State-Trait Anxiety Inventory (Form Y). Palo Alto, CA: Consulting Psychologists Press.