THE ASSURED CLEAR DISTANCE AHEAD RULE - IMPLICATIONS FOR NIGHTTIME TRAFFIC SAFETY AND THE LAW

The assured clear distance ahead (ACDA) rule holds the operator of a m otor vehicle responsible to avoid collision with any obstacle that mig ht appear in the vehicle's path. Although widely considered a fundamen tal responsibility of safe driving, the ACDA rule is routinely violate d by most drivers under nighttime conditions. This fact does not neces sarily imply reckless disregard for public safety, however. Rather the troublesome discrepancy between drivers' behavior and the principles of safe driving may be understood in terms of vehicle operators' lack of awareness of selective losses of visual function that occur in low light. This theoretical perspective holds basic implications both for traffic regulations and for assessment of liability in nighttime road accidents. (C) 1998 Elsevier Science Ltd. All rights reserved.