ENFORCEMENT SYMBOLS AND DRIVING SPEED - OVER-REACTION EFFECT

Driving speed was measured by radar for 240 drivers entering and exiting a target area along a 2-lane highway. The effects of several variables were assessed, including the presence or absence of a speed limit sign, a radar-enforced sign, and a marked police vehicle. Only in the presence of the marked police vehicle were systematic changes in driving speed observed. Most drivers exposed to the marked vehicle showed large reductions in driving speed. These reductions in speed occurred regardless of whether the driver's initial speed exceeded the posted speed limit, and generally went well below the 35 mile/hr limit. Speed reductions in the presence of the marked car thus appeared to reflect an overreaction to the threat of punishment and suggest that driving speed is controlled more by external threat than by drivers' acceptance of the value of safe and energy-efficient driving. (13 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1979 American Psychological Association.