How Understanding the History, Science, and Protocol Can Help You Win Your Case
Driving under the influence (DUI) is a serious charge, but there are many opportunities for drivers to win their cases if they understand the field sobriety testing process. Field sobriety tests (FSTs) are any tests administered on the side of the road, while standardized field sobriety tests (SFSTs) are specific tests that have been researched for accuracy and must follow specific instructions and criteria. The three standardized tests are the HGN, the Walk-and-Turn, and the One-Leg Stand.
Before the early 1970s, officers used several different field sobriety tests to determine possible intoxication. Officers used their own set of instructions and clues, making it very difficult to determine how reliable these tests were. However, in 1975, the Southern California Research Institute came up with the three standardized tests that officers use today. These tests have been researched for accuracy and must follow specific instructions and criteria.
It’s important to remember that whether the test is standardized or not, they are not validated impairment indicators. They can not indicate driving impairment, alcohol impairment, nor drug impairment. The only thing they validate is a statistical probability that somebody’s blood alcohol concentration is at or above the legal limit. And it’s important to keep this in mind when the prosecutor or the officer tries to say that the tests indicate impairment.
Knowing the data and the science behind today’s standardized field sobriety tests can prove valuable for your case. Not only does this provide insight into the accuracy of these tests, but it’s also wise to know the information an officer might use during their testimony. Many officers refer to the San Diego Study as validation for the test they administer. In 1998, the San Diego DUI task force was recruited to help study the reliability of field sobriety tests. The study found that when the three standardized field sobriety tests were combined, they were 91% reliable in determining if a person was at or above the legal limit of .08. However, this study was not peer-reviewed, and there are issues with the reliability of these tests when you look at the number of false positives.
When exploring these tests, it’s important to understand the protocol, clues, and common errors that officers make. For example, if you have an officer who skipped one of the three SFST’s without a medical reason, oftentimes that is a red flag that requires further investigation. You also want to explore what tests were administered to determine the cause for an arrest because some officers like to throw in non-standardized tests like the Romberg, the ABC test, or the finger-to-nose test. These tests are not validated, and there is no way to determine how accurate they are.
In conclusion, when you understand the history, science, protocol, and common areas where officers make mistakes or simply don’t follow the rules, you can better identify false positives and score wins for your client. Research the data and studies available, understand the science behind these tests, and explore the three specific standardized tests: the HGN, Walk-and-Turn, and One-Leg Stand. Knowing this information can make a significant difference in your case.