Pillsbury’s Michael Barr: Clean Air Act Interpretation Unclear

The Environmental Protection Agency is taking recent U.S. Supreme Court rulings to mean that the judiciary is becoming more deferent to its regulatory expertise in Clean Air Act cases. But Pillsbury’s Michael Barr is not so sure.

Speaking at the Texas Environmental Superconference in Austin, Barr said the court cases leave numerous unanswered questions about which Clean Air Act provisions apply to greenhouse gases. He said it is also unclear whether sources of greenhouse gases that would not otherwise need to go through the EPA’s permitting programs could be brought under state regulation through the agency’s proposed Rule 111(d).

Barr said the high court’s interpretation of how the EPA can define “air pollutant” means the agency cannot rely on the landmark case Massachusetts v. EPA to assert the authority to regulate greenhouse gases under the act.

The Supreme Court is likely to have opportunities to weigh in further on the EPA’s powers after the proposed rule is implemented, Barr added.