Even though DUI laws and penalties vary based on the state a motorist resides in, law enforcement officers nationwide administer the same field sobriety tests to motorists they suspect are driving under the influence of alcohol and/or drugs. After these tests are undergone, arresting officers typically document a motorist's performance based on his or subjective account. This judgment, whether accurate or inaccurate, heavily influences a suspected motorist's likelihood of arrest, and in cases when an arrest is made, the outcome of their trial. Of course, other factors such as an officer's testimony and the contents of police reports are taken into consideration when declaring a defendant innocent or guilty of impaired driving. But an individual's performance on a field sobriety test is an undeniably large part of the equation.
Standardized Field Sobriety Tests
Standardized field sobriety tests (SFST) are endorsed by the National Highway Traffic and Safety Administration. The three tests that are routinely administered upon drivers are the one-leg stand test, the walk and turn test and the horizontal gaze nystagmus (HGN) test.
This test is considered a “divided attention” test among law enforcement officers. It requires that a driver raise one foot approximately six inches off of the ground with both arms firmly planted at his or her side for 30 seconds. If a driver sways while attempting to balance, hops up and down or puts their foot down to steady themselves, this is an indication of impairment in the eyes of an officer.
Walk and turn
Officers have noted that this test is executed easiest by people who are not impaired whatsoever. An officer will request that a driver place their hands at their sides and walk to and fro in heel-to-toe fashion. Officers typically give a suspected motorist a number of steps to take before turning and walking in the opposite direction. Signs of impairment include stepping out of line, turning improperly, taking an incorrect number of steps, raising arms to stay balanced etc.
Horizontal gaze nystagmus (HGN)
To conduct this test, an officer will pass a hand-held object, such as a flashlight or pen in front a suspected motorist's face while telling them to follow it with her eyes. The primary purpose of this test is to detect a person's nystagmus, which is an involuntary jerking reaction that occurs when an individual is impaired by alcohol. Officers claim that when a person is sober, their eyes will follow the object flawlessly and easily. But when they are intoxicated, their eyes will lag behind the object or jump in an attempt to correct themselves.
Non-Standardized Field Sobriety Tests
Police officers have been known to conduct non-standardized sobriety tests for suspected motorists. These include requesting a driver to:
- Recite the alphabet
- Count backwards
- Close their eyes and touch their nose with their finger
- Tilt their head backward etc.
The Validity of Field Sobriety Tests
Although field sobriety tests are widely accepted as evidence in a trial and are commonly administered by law enforcement officers across the nation, society and victims of false arrests continue to pose one recurrent question: are field sobriety tests an accurate method of assessing a person's level of impairment? According to several researchers, the answer is no.
One of the most prominent studies dates back to 1975. In an effort to create a more uniform DUI arrest process, The National Highway Traffic Safety Administration (NAFTA) requested that the Southern California Research Institute (SCRI) develop a standardized test that all police departments nationwide could adopt. This task would consist of the California researchers drafting tests that would be simple enough to implement nationwide and accurate enough to back an officer's reasonable suspicion of impairment. Ultimately, the SCRI concluded that the walk-and-turn test, the one-leg stand test, and the Horizontal Gaze Nystagmus test were deemed suitable for administering.
After the researchers developed these tests, they included a section in the study that gauged how well police officers could determine a person's level of intoxication solely with the help of the three tests. The results were alarming. The researchers concluded that the officers correctly assessed an individual's impairment 47% of the time. This means that nearly half the time, an officer could provide a false assessment of a person's impairment - a miscalculation that could lead to the unwarranted arrest and conviction of an innocent motorist.
The study attributed this absurdly large margin of error to the officers' failure to thoroughly follow directions and their flawed sense of judgment. Findings revealed that several officers did not score tests properly (despite having the directions right in front of them) and they repeatedly ignored evidence that revealed a motorist's supposed impairment was rooted in factors other than alcohol.
The test findings were so disappointing that NAFTA ordered the institute to conduct them again in 1981 for signs of improvement. Unfortunately, six years of training did not substantially increase the accuracy of the standardized tests. The study found that officers using the walk-and-turn test were accurate 68% of the time. The one-leg stand test was correct 65% of the time, and the horizontal gaze nystagmus test was accurate 77% of the time. The authors deemed this a success and noted that there a 32% false arrest rate.
But many people believe that this rate is still too high, especially since it compromises the freedom of innocent drivers. Studies reveal that these tests are a tremendous disservice to people who are more than 50 pounds overweight, people that are over the age of 65 and people that have leg, back and hearing problems. Nonetheless, the fact that an individual can pass a sobriety test with one officer, and fail with another is a disconcerting reality.
Experienced Philadelphia DUI Defense Attorney
A suspected driver's performance on a field sobriety test is crucial to the outcome of their case. However, in the event that an officer strayed from regulatory processes and conducted them improperly, your charges could be reduced or even dismissed in certain circumstances. This is why it's important to contact a legal professional who is well-versed in the DUI laws in your state. Contact skilled attorney Joseph D. Lento today.