by John D. Graham and Kenneth R. Richards

The New York Times

February 20, 2009 — There are two alternative approaches that the Obama administration can take to regulate greenhouse gases, like the carbon dioxide emissions from coal plants. One is to craft regulations under existing legal authority, particularly the Clean Air Act. The other is to work with Congress on the enactment of legislation to address climate change. Although either approach is feasible, we believe new legislation is preferable for four reasons.

First, greenhouse gases are global pollutants that have different properties than the pollutants typically regulated under the Clean Air Act. Clean-air rules are aimed at pollutants with regional and local effects (for example, smog and soot) whereas greenhouse gases have the same impact on the climate system, regardless of where in the United States or the world they are emitted.

The Obama administration should work with Congress on an alternative to the Clean Air Act.

Second, regulation of greenhouse gases should be carried out via a system that complements other nations' programs. The Clean Air Act, since it is so legally prescriptive, would not accommodate that need. By contrast, new legislation could be coordinated with developing policies in Asia and Europe.

Third, greenhouse gases, and especially carbon dioxide, are emitted broadly across the economy, not just from a few entities. More than for any other pollutant, it is important to find the most cost-effective mechanisms for reducing emissions. Using the Clean Air Act would lead to complex, and in some cases counterproductive, regulations. This is not the path to follow when there are much simpler and more affordable options.

Finally, the national public debate over climate legislation would provide a forum for stakeholders, politicians and the public to contribute to the design of climate-change policy. Regulatory approaches crafted under existing current authority are likely to be informed primarily by litigation risks, not the publicÕs willingness to incur near-term costs to slow the rate of global climate change.

For these reasons, the Obama administration should work first with the Congress on climate legislation. If that effort is not successful, it could shift to the more awkward regulatory approach under the Clean Air Act as a second-best approach. In fact, we suspect that as a matter of strategy, President Obama may be using the threat of inefficient rulemaking under the Clean Air Act to prod Congress to take decisive action on climate legislation. Assuming he succeeds, Congress should clarify that the new climate law supersedes the Clean Air Act on all matters related to greenhouse gas emissions.