The Commonwealth of Virginia implemented the sign permissive or "eastern" rule permitting right turns on red traffic signals where designated by sign in 1972. In 1975, as a result of the growing national trend toward employing the general permissive or "western" rule (right turn on red permitted except where prohibited by sign) and in the interests of motor fuel economy, the Virginia General Assembly directed the Department of Highways and Transportation and the Highway Safety Division to study right turn on red (RTOR) to determine whether Virginia's sign permissive law "should be retained, rescinded, or amended."

The scope of this study included a survey of literature, a survey questionnaire of Virginia traffic engineers, a telephone survey of traffic engineers in other states, field studies of vehicle delay times and traffic conflicts at 20 selected intersections in Virginia and North Caroline, and an analysis of traffic crashes at 20 intersections in Virginia before and after RTOR was permitted.

The results of this study reveal that right turn on red signals can enable motorists to effect substantial savings in time and concomitant savings in gasoline by reducing the vehicle idling time at intersections. The average saving for right turning delayed vehicles was found to be 14 seconds. Since the general permissive rule for RTOR allows the maneuver at a greater percentage of approach legs that does the sign permissive rule, time and energy savings have been estimated to be greater statewide under the general permissive rule. Estimated savings in gasoline under the general permissive rule would be over three million gallons annually.

No significant increase in traffic crashes was found in Virginia and no increase would be expected with the general permissive rule, as none has been experienced in any other state with either the general permissive or the sign permissive rule. Moreover, study data reveal that traffic conflicts and thereby crash potential are actually reduced under RTOR, and that crashes which do occur because of RTOR are generally not severe.

When the total impact of RTOR was considered, the evidence was found to support the recommendation that Virginia implement the general permissive rule for right turn on red.