Supreme Court Ruling Backs Most EPA Emission Controls

The Supreme Court today threw out part of U.S. EPA's air permitting program for heat-trapping greenhouse gases.

In a 5-4 vote, the court's conservative wing held that EPA could not require stationary sources to obtain air pollution permits and install pollution controls because they emit only a specified amount of greenhouse gases.

The court also ruled that EPA unlawfully interpreted the Clean Air Act when it revised the numeric tonnage thresholds for greenhouse gases that force factories, power plants and on industrial facilities to obtain a permit.

But the ruling's impact on EPA's larger regulatory regime is likely limited.  In a separate part of the decision, EPA won the votes of seven justices who held the agency could require facilities to limit greenhouse gas emissions if they already qualified for the permit program because of emissions of conventional air pollutants.

Conservative Justice Antonin Scalia, writing for the court, noted EPA's broad interpretation would account for 86 percent of the country's greenhouse gases.  But limiting the permit requirement to the "anyway" sources would cover 83 percent, a difference of 3 percent.

Supreme Court Ruling Backs Most EPA Emission Controls