The Problem with Standardized Field Sobriety Tests

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The Problem with Standardized Field Sobriety Tests

If you’re pulled over for the suspicion of driving under the influence, you know that there are a variety of checks that officers can perform to determine whether or not you’ve been drinking. There’s just one problem: most field sobriety tests are designed for you to fail. Scientific study has proven that many field sobriety tests have little measure of reliability in helping an officer predict whether or not the subject has a blood alcohol content over the legal limit.

Only three of the tests currently in use are even somewhat reliable: the walk and turn (WAT) test, the one leg stand (OLS) test, and the horizontal gaze nystagmus (HGN) test. Even these tests unfortunately have significant margins for error, and other reasons for failure aren’t ruled out by their use. There are a number of reasons why even the most realistic test might be flawed. Standardized Field Sobriety Tests (SFSTs) must be done in the manner approved by their manual and given proper grades according to the officers administering the test. Unfortunately, many of those officers have been trained by other officers, who have been trained by the officers before them, and in so doing, they’ve lost the scientific methodology necessary to correctly evaluate the test.

Sloped Testing Area: The walk and turn test and the one leg stand test require a relatively flat stretch of land in order to be effective. A sloped testing area can make it more difficult for the subject to keep their balance, therefore yielding a false positive result.

Lack of a Baseline: Does the officer know what a subject who isn’t under the influence of drugs or alcohol will look like performing the test? There are a wide range of potential results that could occur as a result of circumstances that have nothing to do with alcohol consumption, and an officer who doesn’t have a realistic measurement of the baseline could improperly convict a subject of driving under the influence for this reason.

Poor Understanding of the “Why”: If the officer doesn’t understand the reasoning behind the test, the results could be measured improperly.

Complex Instructions are Given in a Short Period of Time: If a subject has been pulled over for a suspicion of driving under the influence, they’re already on edge and not performing at their best due to the stress. Issuing complex instructions too quickly makes it even more likely that they won’t be able to process the information and perform the way they need to.

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The HGN Test and Vision Problems: The HGN test measures the involuntary movements of the eye to the side. Contacts, vision problems, and some diseases that impair visual function can change the way a perfectly sober individual performs on the test.

Illness or Disease: A subject who has been ill or who has a chronic disease might perform poorly on many field sobriety tests, especially those involving balance or coordination.

Nervous Conditions: Any subject who suffers from a nervous condition will not perform as well on a field sobriety test because of their reaction to the stressful circumstances. Even involuntary eye movement can be impacted significantly by nervous reactions.

Handicaps and Injuries: Subjects with handicaps and injuries may find it difficult to correctly complete field sobriety tests that require balance or coordination.

Lack of Coordination: Some subjects are simply clumsy and are unable to complete tests that require balance and coordination as a result. Their unimpaired state is comparable to other drivers who are under the influence of alcohol.

Age: As people grow older, their ability to complete simple balance and coordination tasks changes. Officers who aren’t familiar with age-related changes to stability and coordination may incorrectly evaluate inebriation.

In many cases, a top-notch defense attorney can cross-examine an officer using his own training methods and get a SFST thrown out in court. In many cases, the tests are conducted in a manner not approved by the SFST manual or are graded improperly, and a good lawyer will be able to use this to have the field sobriety test stricken from the record. It’s also important to note that field sobriety tests are voluntary, and that many people who have chosen to take them end up wishing that they hadn’t. In these circumstances, a top-notch defense attorney is paramount in preventing the potential negative consequences of a DUI that has been determined through a field sobriety test.

Ben Landman is a content and communication specialist at Ben enjoys social networking, composing music and spending time with family.