Are Field Sobriety Tests Accurate?
Chicago DUI Defense Lawyer
If you were arrested for
DUI and are facing charges based upon field sobriety test results, you most
likely are wondering how accurate these tests are. With a complete understanding
of how these tests are administered and their inherent faults, I can provide
my experienced counsel as a lawyer to help you.
field sobriety tests to yield the most accurate results possible, they must be administered
in a precise manner. It is also important for three particular tests to
be administered: the Horizontal Gaze Nystagmus, Walk-and-Turn and One-Leg
Stand. Even when these tests are administered accurately and the results
evaluated properly, however, their results will not be 100% accurate.
According to NHTSA (National Highway Traffic Safety Administration) research,
these tests may yield results of varying accuracies*:
Horizontal Gaze Nystagmus (HGN) – proper classification of approximately 88% of subjects.
Walk-and-Turn (WAT) – approximately 79% accuracy.
One-Leg Stand (OLS) – accurate in approximately 83% of subjects.
When all three tests are administered accurately, they may yield accurate
results in 91% of cases.
Field Sobriety Tests
Although a field sobriety test may be considered to properly determine
whether a driver is intoxicated or under the influence of a controlled
substance, they are not completely accurate. In addition to being prone
to improper administration by law enforcement, there is the possibility
that factors unrelated to
drugs or alcohol may contribute to a "failed" field sobriety test.
A natural inability to balance, age, weight, physical injury, nervousness
and even the shoes a driver is wearing may impact his or her performance.
After all, these tests gauge balance, coordination and an ability to follow
instructions – all things that may naturally vary from driver to driver.
If you would like to challenge the results of your field sobriety tests,
contact the Law Offices of Mitch Furman today.
*According to NHTSA "Appendix A Standardized Field Sobriety Testing."