The Washington, DC city government joined a bicycling activist group yesterday to launch a campaign to block motorists using slow-moving "pace cars." The District Department of Transportation (DDOT) and the Washington Area Bicyclist Association is handing out "neighborhood pace car" stickers to any drivers who pledge to block any motorist who attempting to drive above the speed limit.

"We are always looking at innovative ways to calm traffic," DDOT Director Emeka Moneme said. "It is in everyone's interest to sign up."

The majority of DC city streets are posted at 25 MPH. The program is expected to begin in neighborhoods, then expand throughout the city.

"We only need a small percentage of vehicles acting as pace cars to slow traffic city-wide," the bicycle activist website explains. "Many people who sign up for the pace car program have already been acting as unofficial pace cars. They report that incidents of road rage decrease when they badge their cars as pace cars."

The idea for rolling roadblock programs is not new. Groups such as the National Motorists Association would perform one-off demonstrations of the need to repeal the 55 MPH national maximum speed limit by encouraging a number of cars to drive together on one stretch of road at no more than 55 MPH. The speed limit law was ultimately repealed in 1995. A similar experiment by student filmmakers last year captured the dangerous conditions caused by the pace car concept (view video 1, view video 2).

An on-going rolling roadblock program was adopted early last year by government officials in Doncaster, England. Safety experts blasted the program at the time.

"Road safety works best when drivers co-operate together and adjust their speed to suit the hazard," said Paul Smith, founder of the Safe Speed road safety campaign. "This vital behavior is being gradually, inexorably and dangerously replaced with a 'driving by numbers' approach."

"Many speed limits are now set against government advice and too low for driving conditions," added Mark McArthur-Christie with the Association of British Drivers. "Where this is the case, following drivers bunch behind the lead car with greatly reduced separation distances. When the car in front brakes, the cars in the column can't stop in time. We're concerned that acting as a pace car is putting yourself at risk of a rear-end collision."