When police officers in Maryland stop a driver whom they suspect is impaired, they may ask the driver to take a series of field sobriety tests. These standardized field sobriety tests are utilized by officers to gauge a person’s impairment due to alcohol or drugs. Law enforcement agencies can use field sobriety test results to establish probable cause for DUI arrests, so many people assume that the tests are infallible and accurate. However, these tests are not 100% accurate.
Accuracy of field sobriety tests
In the late 1970s, a study was conducted by the National Highway Traffic Safety Administration (NHTSA) and the Southern California Research Institute (SCRI) to evaluate the accuracy of dozens of field sobriety tests. In the study, the SCRI asked 10 officers to watch subjects perform various tests. After viewing the subjects, they asked the officers to decide whether the participants had a blood alcohol content (BAC) of .10 or higher.
According to the study, the officers’ error rate for determining BAC level was only 47% initially. The NHTSA and SCRI teamed up again to standardize the administration of certain tests in hopes of reducing this error rate. Reportedly, they found that standardizing the tests gave the walk and turn a 68% accuracy rate, the one-leg stand a 65% accuracy rate and the horizontal gaze nystagmus a 77% accuracy rate. When all three tests were used together, the study found they were correct about 82% of the time.
Obtaining legal assistance
Many experts will agree that field sobriety tests can be inaccurate and are not a scientifically proven way to establish drunk driving charges. Any person in Maryland who is arrested and charged with DUI can seek the services of a legal representative to help them defend against these charges. An experienced attorney can protect personal rights and provide invaluable guidance.