If a police officer pulls someone over and suspects he or she is under the influence, the officer may ask him or her to perform a field sobriety test. This encompasses a series of three physical exams that test your coordination, balance, and other factors that assess your sobriety.
However, field sobriety tests are not completely accurate for more than one reason.
Subjectivity
One of the main issues with field sobriety tests is that they are subjective in nature, relying heavily on the officer’s interpretation and judgment, which can vary from person to person. This can lead to inconsistencies in test administration and evaluation. The twitchy eyes of an exhausted person may look very close to the eyes of an intoxicated person to one officer, but normal to another.
There is a lack of standardization in administration and evaluation. While there are guidelines, officers do not always follow them rigorously.
Variability
Another factor that can affect accuracy is the variability in how individuals perform the tests. Variables such as age, physical condition and nervousness can all impact a person’s ability to perform the tests correctly. Additionally, individuals with certain medical conditions or disabilities may have difficulty performing the tests even when sober.
Environment
External factors such as weather conditions, road conditions and the presence of distractions can also affect the tests. For example, a slippery road or a noisy environment can make it more difficult for a person to perform them accurately.
The reliability of field sobriety tests is in question. Individuals have the right to refuse a field sobriety test. A false negative can and most likely will end up as evidence against them in court.