Supreme Court Rules on PM/Ozone Case.

On February 27, the U.S. Supreme Court issued its decision in the case challenging EPA's revised National Ambient Air Quality Standards (NAAQS) for ozone and particulate matter (PM). The unanimous decision said the law does not require the government to consider the financial cost of reducing harmful emissions when it sets air-quality standards. The Clean Air Act (CAA) "unambiguously bars cost considerations" from the process of setting air-quality standards, "and thus ends the matter for us as well as the EPA," wrote Justice Antonin Scalia. The Court also ruled against industry arguments that EPA took too much lawmaking power from Congress when it set the tougher air standards in 1997. Although the Court disagreed with industry's challenge that EPA exceeded its authority in setting the air standards, the Court did decide that the agency overstepped its regulatory authority in attempting to impose the new ozone standard. The ruling, stated that EPA's implementation strate gy was unlawful, and the agency was directed to develop a reasonable implementation strategy. The Supreme Court ruling also allows the Washington, D.C., Circuit Court of Appeals, to which the standards were remanded, to overturn the air quality standards on other grounds.