After the initial 1977 study into field sobriety testing conducted by the Southern California Research Institute a second study was commissioned. In 1981 the National Highway Transportation Safety Administration (NHTSA) awarded a second contract for the study of the three standardized tests. These tests were the Horizontal Gaze Nystagmus, Walk-and-Turn, and One-Leg Stand.
The purpose of the study was to establish a consistent manner in the administration of the tests. This required standardized guidelines, demonstrations, instructions, and the manner in which the tests are scored.
Partway through the study, researchers added an additional scoring standard. Researchers added a divided attention portion to the field sobriety tests. This simply means that officers are providing suspected DUI drivers with two tasks to be completed simultaneously. One example of this is observed in the Walk-and-Turn test. Officers will ask a driver to stand with one foot in front of the other while listening to the instructions of the officer.
During the study in 1977 it was found that arresting officers were mistaken 47% of the time. In the 1981 study, researchers found that there was improvement but officers were still incorrect in their decision 32% of the time.
There is a reason that the study showed an improvement. During the study, test subjects were closely monitored and around 78% of the test subjects had a blood alcohol content (BAC) of .15 or higher or a BAC of .05 or lower. This is interesting because individuals with a BAC of .15 or higher are clearly intoxicated and any officer’s decision making will be increased due to this fact. The same may be said for those individuals with a BAC of .05 or lower. These individuals would not be intoxicated to the point where their driving would be impaired. Based on theses figures, only 22% of the test subjects had a BAC in a mid-range BAC of .05-.15. This is an obviously more difficult range for officers to make valid decisions.
These studies show that the accuracy of the field sobriety tests cannot be trusted. The attorneys at Parkman & White, LLC have been trained in the administration of the field sobriety tests and know what issues to look for. An experienced DUI attorney may be able to assist you in showing a Judge or Jury the fallacies associated with these tests.