The fuel economy of an automobile, measured in miles per gallon (MPG), is the distance it can move using one gallon of fuel. In 1975, in the midst of concerns about oil consumption, the U.S. Congress passed a law establishing the Corporate Average Fuel Economy (CAFE) standards, which required an increase in the fuel economy of all new cars and light trucks starting in 1978. The law required that each manufacturer meet the same standard but that a manufacturer's cars and trucks be treated differently since trucks were primarily used for work at the time. It mandated an average fuel efficiency of 27.5 MPG for cars by 1985, roughly doubling car fuel economy over ten years. The car standard remains the same as of 2003. The law also directed the Department of Transportation (DOT) to establish a standard for light trucks, defined by the DOT to include sport utility vehicles...