DUI Detection — The Vehicle In Motion

Police officers are trained in DUI detection and enforcement during initial police training. Police officers are trained using standards and procedures put forth by the National Highway Traffic Safety Administration (NHTSA). Police officers are taught about the effects of alcohol and drugs on an individual and how using alcohol, drugs, or a combination of alcohol and drugs impacts driving.

There is no typical DUI case. Each case is unique, as are the circumstances surrounding the driver who is arrested. Notwithstanding, a DUI stop often begins in the same way. Typically, a police officer is riding in a squad car making observations of traffic. In accord with NHTSA training, a police officer is trained to look for certain clues of impaired driving.

NHTSA publishes training and educational material for use by police officers in DUI detection and enforcement courses. “The Visual Detection of DWI Motorists” is one such publication. (NHTSA publication number DOT HS 808 677). The vehicle in motion portion of DUI detection is broken down into four parts. 1) Problems in maintaining proper lane position, 2) Speed and braking problems, 3) Vigilance problems, and 4) Judgment problems.

Problems in maintaining proper lane position include weaving, weaving across lane lines, straddling a lane line, swerving, turning with a wide radius, drifting within a lane, and almost striking a vehicle or other object.

Speed and braking problems consist of stopping too short, too jerky, or too far from the stop line, accelerating or decelerating for no apparent reason, varying speed for no apparent reason, or traveling more than 10 miles per hour below the posted speed limit. Interestingly, exceeding the posted speed limit is not considered a sign of impairment during the vehicle in motion detection phase.

NHTSA lists vigilance problems such as driving in opposing lanes or wrong way on one-way, slow response to traffic signals, slow or failure to respond to police officer’s signals, stopping in lane for no apparent reason, driving without headlights at night and failure to signal or making signals that are not consistent with driving actions.

Finally, NHTSA enumerates problems with judgment including following too closely, improper or unsafe lane changes, illegal or an improper turns, driving on other than the designated roadway, stopping inappropriately in response to a police officer’s signal to stop, inappropriate or unusual behavior inside the vehicle, or appearing to be impaired.

Knowing how the police officer is trained helps a skilled DUI defense attorney impeach the police officer’s credibility if the officer deviates from police training. Without a good knowledge of NHTSA training, a DUI defense attorney is at a significant disadvantage when defending a client. Steven Herzberg has the knowledge of DUI police training to know how a police officer is supposed to be trained and when a police officer deviates from police training. This knowledge can be the difference between winning or losing your DUI criminal case.