EPA Administrator, Stephen Johnson, appears to be losing credibility over his December 19, 2007 denial of a California petition for a federal waiver that would allow the state to require reductions in greenhouse gas emissions from vehicles (US New and World Report, Environmental News Service). The Administrator and his proponents argue that a unified, federal standard is the common sense approach for regulating greenhouse gas emissions. They reference the recently passed energy bill that includes an upgrade to CAFE standards requiring fleet average fuel economy to reach 35 mpg by 2020. Opponents argue that the Administrator went against advice from EPA staff and that his decision was politically motivated.
California has had significant freedom in setting it's own air quality standards under provision 209(b) of the Clean Air Act. This has allowed the state to enact more stringent regulations of air toxins, such as NOx, particulate matter, CO, etc, over federal standards. The provision also gives other states the option to follow suit and implement the California standards. In this most recent scuffle between California and Washington, 18 other states had plans to enact California's so-called 'Clean Car Act'. The states have sued the EPA to overturn the December 19 decision.
The California legislation would require a 23 percent cut in carbon emissions from new cars by 2012 and a 30 percent cut by 2016. Considering the fact that 19 states would implement this plan, I don't see how this could not be considered a 'unified' approach to dealing with greenhouse gases. Opponents of the California legislation say that automakers would bail on the state's market; I personally do not believe that automakers would bail on markets in 19 states. In addition, the Japanese automakers would enjoy taking further market share from their American counterparts.
I am not fully versed on the intricacies of the Clean Air Act, and the 209(b) provision in particular, but I believe that California should be allowed to forge ahead with it's ambitious plans. If the Administrator's ruling is overturned, and California is granted the waiver, California and the 18 other states will inevitably place tremendous pressure on Washington to play catchup.