In 2010, the EPA introduced a new set of regulations designed to control carbon dioxide emissions from light and heavy vehicles as well as generators and industrial and utility sources.

[7] When the EPA attempted to apply the same standards to any source of greenhouse emissions, the Court objected that "would radically expand those programs, making them both unadministrable and unrecognizable to the Congress that designed them.

[8] However, the Court stated, "An agency has no power to 'tailor' legislation to bureaucratic policy goals by rewriting unambiguous statutory terms.

Breyer argued that the EPA should have been allowed to interpret the "any air pollutant" language broadly to include greenhouse emissions as well: "I do not agree with the Court that the only way to avoid an absurd or otherwise impermissible result in these cases is to create an atextual greenhouse gas exception to the phrase 'any air pollutant.

"[13] He cited two scenarios of incompatibility between greenhouses gases and normal pollutants, which eventually caused the EPA to declare that officials may disregard some provisions in the Act[14] or to give authorities "a great deal of discretion.