Some readers from New Jersey may be interested in learning more about the Standardized Field Sobriety Test. The SFST is actually a compilation of three separate tests created by the Southern California Research Institute and sponsored by the National Highway Traffic Safety Administration. The compilation includes the horizontal gaze nystagmus test, the walk-and-turn test and the one-leg-stand test. All three are intended to aid police officers in detecting someone who has been driving while intoxicated.
Someone who is under the influence of alcohol may be unable to visually track a moving object in some circumstances. The HGN test scrutinizes whether or not the eye jerks and if the jerking occurs at a predetermined angle. If these symptoms are present in sufficient quantity in one or both eyes, it is considered likely that the subject's blood alcohol content will be above the legal limit.