Potential Issues With Standardized Field Sobriety Tests (SFST)


What are Standardized Field Sobriety Tests?

The Standardized Field Sobriety Tests (SFST) consist of three law enforcement tests used in DWI and DUI detection to establish probable cause for arrest. The tests consist of the one-leg stand, the walk-and-turn and the Horizontal Gaze Nystagmus. None of these tests are admissible in court if not done properly. Even when accurately done, the tests are not 100% reliable in predicting impairment.

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Introduction to Standardized Field Sobriety Tests (SFST) and Potential Issues

by William C Reynolds

There is a broad range of behaviors which are acceptable as indicators of potential DWI to law enforcement officials. While the number of behaviors is extensive, the amount needed to progress a case from observation of a subject to arrest of the same subject can be relatively small. If an officer feels that a subject might be driving while impaired, it is his duty, and the public should demand that he take every step possible to build a solid case based on as much reliable evidence as he can readily obtain.

Nationwide, the majority of officers who are trained in DWI detection are trained to the standards presented by the National Highway Traffic Safety Administration (NHTSA) in the manual “DWI Detection and Standardized Field Sobriety Testing”. According to the manual, the ultimate goal of training officers is,
To increase deterrence of DWI violations, and thereby reduce the number of crashes, deaths and injuries caused by impaired drivers.

It would be difficult to find a person to argue that this is not a necessary response to the well documented problem of drunken drivers on the roadways of the United States. With this issue and this goal in mind, NHTSA contracted with the Southern California Research Institute (SCRI) in late 1975 to determine the accuracy of roadside field sobriety tests for drivers who may be impaired. Over several years, a total of three reports were published.

The first report, Psychophysical Tests for DWI Arrest, authored by Marcelline Burns, Ph.D. and Herbert Moskowitz, Ph.D. used ten officers performing a variety of tests on 238 test volunteers in order to determine which tests were most likely to help an officer determine impairment in a subject. Some of the tests which were evaluated were One-Leg Stand, Walk-and-Turn, Finger-to-Nose, Finger Count, Horizontal Gaze Nystagmus, Tracing, and a variety of alternate tests. The individuals were each scored on a 1 to 10 scale based on the officer’s opinion of their performance during the test. At the end of the sequence of tests, the officer was asked to conclude based on a blood alcohol level (BAC) of.10% if the subject would be arrested or released had the testing occurred roadside.

Several interesting things were learned during the testing. First, SCRI reported that HGN testing proved correct 77% of the time for a BAC over.10%, WAT 68% and OLS 65%. However, SCRI also reported that the scoring on the tests by the officers indicated that they had applied a lower level of impairment as a decisive factor for arrest than would normally be applied in the field. Officers were anticipating impairment so their awareness was heightened while looking for impairment in each individual. The result was a high rate of false-arrest decisions. The majority of the test methods were discarded from potentially being useful as standardized field sobriety tests for reasons ranging from their level of accuracy to the difficulty an officer would have administering the test on the side of the road or in a parking lot.

Three test, the One-Leg-Stand (OLS), Walk-And Turn (WAT), and Horizontal Gaze Nystagmus (HGN) were found to be the most reliable, easiest to administer on the side of the road and most accurate. The paper went on to conclude in regards to the three tests that,

If balance and walking skills are examined, and the eyes are checked for the jerking nystagmus movement, the officer will have as much information about intoxication level as can be obtained at roadside.

These three test have become the basis for standardized field sobriety training (SFST) for police officers in the United States and one of the key subjects of the NHTSA manual used to teach proper DWI recognition and enforcement to officers.

The validity of the use of HGN, WAT, and OLS as evidence of driver impairment is based on a very specific test sequence as well as precise administration of each test. Like any scientific process, in order to get an accurate result, the officer conducting the test must follow the procedures set forth in the NHTSA DWI Detection and Standardized Field Sobriety Testing manual. The manual specifically states that,

It is necessary to emphasize this validation applies only when:

o The tests are administered in the prescribed, standardized manner

o The standardized clues are used to assess the suspect’s performance

o The standardized criteria are employed to interpret that performance.

If any one of the standardized field sobriety test elements is changed, the validity is compromised.

HGN, WAT and OLS, were tested and recognized as the standardized field sobriety tests by trained scientific researchers under laboratory conditions. Even later studies which were conducted to validate the use of the tests were overseen by researchers in conditions which could almost be considered sterilized compared to the normal roadside conditions an officer typically has to operate in. Unfortunately, this is an area where many officers begin to go wrong in regards to collecting accurate evidence against a suspected intoxicated driver. This is not necessarily a conscious effort on the part of the officer to taint evidence but could have many other explanations.

What often happens is that over the course of time, many officers modify the SFST either for convenience or as a time saving measurement. An officer may not even consciously be aware of the fact that he is doing this. Many officers receive initial training for SFST while in the police academy and then rarely if ever attend follow up training. The officer simply may feel that his method of conducting the tests will suffice as proper evidence. This may mean that the tests are not conducted in the proper order, parts of the administrative procedures are left out, or the officer strays completely from the scientifically validated test and conducts his own modified version. No matter what the reason, the fact is, according to the NHTSA manual, if the tests are not performed exactly as instructed, the validity has been compromised. According to the NHTSA report “Development of Standardized Field Sobriety Tests”, court rulings in a small number of states have held that slight deviations from NHTSA standards should not completely negate tests which were improperly administered. Although the results of the tests may not be suppressed as evidence, it certainly brings into play the officer’s experience and the basis for his particular methods. Unfortunately what “slight” variations are allowable is not clear.

Officers are trained on the specific administrative procedures that are necessary for conducting HGN, WAT and OLS. It is important to reiterate that with the exception of a few states who have case law which states otherwise, the officer cannot deviate in any manner from the testing procedures described. As stated earlier, the validity of the SFST is based on scientific research conducted on these tests given in the proper order in a very specific manner. Remember the NHSTA manual specifically states,

If any one of the standardized field sobriety test elements is changed, the validity is compromised.

Prior to conducting SFSTs the officer must go through Phase One: Vehicle in motion. This phase is when the officer observes the vehicle in motion and takes note of any possible cues which may lead him to believe that the operator is intoxicated. There are a total of 24 cues listed in the NHTSA manual which are said to allow the officer to predict a BAC of.08% or greater during night time conditions. What is interesting about the cues is the fact that many police reports show the officer only recording one or two cues during the Vehicle in motion phase. Another interesting aspect of the cues is how many of them can be related to other activities.

For example, a young mother running late to get home to her child and babysitter leaves work from a fairly well lit parking lot one evening and forgets to turn on her headlights. As she enters the roadway, she drops the cell phone on which she had called the babysitter and while grabbing for it, pulls into the far lane of traffic instead of the corresponding lane. This causes her to pull directly into the path of oncoming traffic and another vehicle. The anxious young mother overcorrects pulling onto the shoulder of the roadway briefly and then accelerates rapidly in an attempt to avoid any other traffic that is possibly heading in her direction.

While this event certainly has a very plausible explanation, in the eyes of an overzealous police officer, the young mother has just shown five cues of possible impairment. It is hopeful that the officer would stop the mother, learn the facts and then proceed accordingly however this is not always the case. This brings up a point of contention in regards to these particular indicators. The idea behind the cues is that they are signs that an officer would likely see committed by a person who was driving while intoxicated. However what needs to be kept in mind is that just because a person shows a cue, this does not necessarily mean that they are intoxicated. Obviously this is a “chicken or the egg” type of argument but if officer discretion and proper training is not followed, simply following cues may mean an innocent citizen is accused of a crime which they did not commit and detained possibly for the wrong reason.

After the officer stops the vehicle, he is given another set of post stop cues to follow to help him in determining if the driver is intoxicated and more importantly, if the officer should continue on to phase two of the stop. These cues are observed by the officer while he is approaching the driver’s vehicle and before he begins a dialogue with the driver.

In the example, it is very likely that the young mother, who is now agitated, scared due to her near miss of another vehicle and most likely nervous, will probably have some difficulties with some of the post stop cues. Again, while the subject in the example is not intoxicated, she is meeting some of the same criteria that an intoxicated motorist might meet.

If the officer has any indication that the driver is impaired, he will then move to Phase Two: Personal Contact. Phase two is broken into two parts. The first part is for the officer to approach the driver. With the driver still in the vehicle and while the officer is conducting a brief interview, he should be observing and taking note of any possible indication of intoxication. If the officer suspects that the subject is intoxicated, he may proceed to the next segment of phase two. This second component will have the officer request that the driver exit the vehicle for further testing. It is possible that an officer could go directly to phase two. For example during a DWI checkpoint or at the scene of an accident the officer is not likely to have an opportunity to observe the subject operating the motor vehicle and if he does, it will commonly only be for a brief period of time. Of course similar to the first part of phase two, the officer must still observe the driver and note any possible indication of intoxication.

Similar to Phase One, the officer is given a list of possible clues to be aware of which may indicate that the driver is intoxicated. These clues are categorized as clues that the officer can hear, see or smell. While some of these clues such as alcohol containers and drug paraphernalia might be difficult to explain, others such as bloodshot eyes, soiled clothing, inconsistent responses and the odor of a breath spray could very well be seen on a person such as the young working mom.

Again, there are a great number of clues for the officer to observe, many of which might have little or nothing to do with an individual being intoxicated. This is where it becomes important for an officer to use his experience, training and discretion to decide whether or not he should continue on with Phase Three: Pre-Arrest Screening or follow a different path. In the example given above, experience and standardization would go a long way towards ensuring that an officer recognized that the young mother made some dangerous traffic violations but they were not caused by alcohol impairment.

On April 17, 1998, Los Angeles, CA attorneys Bruce Kapsack and Hudson Bair deposed Dr. Burns in a case related to the relevancy of SFST as an indicator of impairment. Burns explained the history of the development of SFST and answered several questions related to the use of SFST by officers. At one point Burns was asked how important standardization of the tests were to which she replied,

Well, if the tests are going to have meaning as objective
measures, they have to be administered in a standardized way. If Officer A- let’s use Walk and Turn, for example. If Officer A uses 10 steps down and 12 steps back, there’s nothing inherently wrong with that, and it may give him a good idea whether he’s looking at impairment or not, but it’s not the standardized instructions.

Burns goes on to explain that slight variations in some of the minor aspects of the test such as using the word “pivot” instead of “turn” would not necessarily invalidate the test. However, if the major portions of the test were changed by the officer, as in the example above, then the test is no longer the same standardized test which was researched by SCRI. Unfortunately Burns never goes into detail as to what can be considered a “major” or “minor” feature of the test other than the examples listed. So while Burns appears to be an advocate of standardization, there also appears to be in her opinion some room for leeway. This makes an interesting conundrum for officers.

It is easy to see that police officers have a great deal of responsibility trying to maintain order and safety on the highways of America. The NHTSA Standardized Field Sobriety Tests go a long way towards assisting officers in curbing drunk driving. It must be remembered however that if an officer decides to step outside of the standards, there is a good likelihood that the evidence he provides will be questioned on its validity. There is even the possibility that the officer himself will be taken to task for providing questionable evidence.

Missouri licensed private investigator, William Reynolds of Brighton Lewis, St. Louis MO, is a nationwide DWI consultant and an instructor of the NHTSA DWI Detection and SFST program. Mr. Reynolds trains legal professionals and law enforcement in proper DWI procedures. Mr. Reynolds also serves as a DWI consultant and is available to assist attorneys with expert advise on all aspects of the NHTSA DWI Detection and SFST program. For further information or to contact Mr. Reynolds, please go to http://www.brightonlewis.com

Article Source: EzineArticles.com

Killeen, Standardized Field Sobriety Tests Attorney:

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