Another way for cities to promote better transportation policy and reduce Carbon dioxide emissions

DC has a fleet of cars, using natural gas, but still cars, for the parking enforcement function. I noticed in an article Christopher sent to me about parking in San Francisco from the Chronicle, "S.F. plans to raise parking fines," that the enforcement person is wearing a bike helmet. And on the SF Municipal Transportation Agency website, they show a bicycle-based parking enforcement officer writing a ticket as well.

In many areas of the city, this function could be performed by bicyclists, not car drivers, and it's a lot cheaper to buy and maintain bicycles than it is to buy and maintain cars.