DUI Information
Field Sobriety Tests
These psychophysical tests are used to determine the driver’s physical/mental impairment. They target the required ability to drive safely. Driving involves multitasking to ensure safe vehicle operation. The tasks include steering, breaking, and acceleration control, and reactions to constantly changing driving environment. Alcoholic influence on a driver may impair him/her to concentrate on these tasks at once. An example is: inadequate division of attention to all the tasks at a single point of time.
Divided tasks are designed to evaluate mental and physical capabilities a person needs to safely drive a car. They include decision-making, balance, steadiness, short-term memory, co-ordination of limbs. Field Sobriety Tests judge two or more of these capabilities.
The most common Field Sobriety Tests used are Horizontal Gaze Nystagmus tests, Walk & Turn test, and the One Leg Stand test. They indicate a reliable result for intoxication although they are not 100% accurate.
Three tests were developed by researchers funded by the National Highway and Traffic Safety Administration (NHTSA). Failure of any tests, according to the researchers, means the person has an alcohol concentration of greater than .08.