How carbon emissions got caught up in a Supreme Court showdown

A man walks up the steps of the US Supreme Court.

Enlarge / A man walks up the steps of the US Supreme Court. (credit: Mark Wilson/Getty Images)

Thursday's Supreme Court decision regarding the use of the Clean Air Act to regulate carbon dioxide emissions from power plants comes down to two specific issues: Should the Supreme Court take the case at all; and did Congress delegate sufficient authority to the EPA for it to implement a specific regulatory scheme first proposed during the Obama administration?