Each of these questions have bearing on Massachusetts v. EPA. In this case, there are three basic questions: whether the petitioners have standing, whether the EPA is authorized to regulate CO2 and other greenhouse gases as pollutants (including whether CO2 should be properly classified as a pollutant) – and if they are, whether they have discretion not to regulate greenhouse gases as pollutant, and who should decide these issues.
Dealing with the latter two points first, I would argue that it’s good the Supreme Court took the case and I hope that they settle the matter once and for all. Writing a decision that would extend to other pending climate change lawsuits and state laws and regulations. On the question of whether or not the United States begins to limit energy and lifestyle choices by regulating greenhouse gas emissions is, as a matter of Constitutional law, solely within the purview of the Congress of the United States: not the Executive Branch through its administrative agencies, not the states, and not the Courts themselves.
While I don’t think CO2 is a pollutant and thus doesn’t fall under the Clean Air Act, the language of the statute is ambiguous and the Court could find that the plain language gives the EPA such authority. However, in a manner similar to the Brown & Williamson case, the court could find that because CO2 is ubiquitous – it’s necessary to life and we don’t know how to live and generate enough energy to sustain modern society without emitting it – and because any regulatory response that would have a credible chance of reducing future warming would arguably have a wrenching effect upon the economy, and because Congress has debated questions of the causes of climate change, its potential impacts and the appropriate responses for nearly 20 years; Congress never intended the Clean Air Act to address the question of climate change and if it wants the EPA to do so, it is up to Congress to so act. While the federal Clean Air Act authorizes the EPA to regulate emissions which "cause, or contribute to, air pollution which may be reasonably anticipated to endanger public health or welfare,