DUI Field Sobriety Tests

When there is suspicion that a driver is intoxicated, a police officer may request the driver to complete various standardized field sobriety tests prior to administering a breath, blood or urine test. Field sobriety tests consist of various cognitive and coordination tasks designed to assist a police officer in determining if a driver is under the influence of alcohol or drugs. The failure to successfully complete these tests is typically used as probable cause for an arrest for driving under the influence of alcohol or drugs.

Three standardized field sobriety tests were initially developed in the late 1970s by the Southern California Research Institute in association with the National Highway Traffic Safety Administration (“NHTSA”). The three standardized field sobriety tests are the horizontal gaze nystagmus (HGN), the walk-and-turn test and the one-leg stand test. Additionally, police officers use a number of non-standardized field sobriety tests to assist them in determining impairment. Common non-standardized field sobriety tests include counting backwards, reciting the alphabet, and the finger-to-nose test.

Critics of field sobriety tests include criminal defense attorneys, psychologists and other experts who dispute the reliability and validity of the results of these tests. Although the field sobriety tests consist of simple tasks, their administration and analysis can vary widely and are in large part dependent upon the training level of the officer administering the test. In that regard, critics of field sobriety tests argue that they are designed to fail.

That is to say, some critics believe that the tests by their very nature are difficult for even a sober person to pass and therefore, they rarely result in a determination that a driver is not intoxicated. Take, for example, the walk-and-turn test or the one-leg stand test. Both tasks are simple in nature, but can be complicated to perform on the uneven shoulder of a busy highway. Additionally, physical limitations may skew results as well. For example, a person who has had knee surgery or is uncoordinated may have difficulty completing these two tests.