Engine Manufacturers Association (EMA) v. South Coast Air Quality Management District (SCAQMD)


U.S. Supreme Court

NAHB Involvement

The SCAQMD, which regulates air quality in the Los Angeles area, adopted regulations that require the purchase of vehicles with cleaner engines than required by federal standards. The federal trial and appeals courts upheld the local, more stringent regulations. The Supreme Court agreed to take the case, to decide whether the federal Clean Air Act (CAA) pre-empts states from setting certain emissions requirements. Because of the impacts this case could have, particularly on emissions from construction equipment used by our members, NAHB joined an amicus coalition. The coalition’s amicus brief was filed on Aug. 29, 2003. Oral argument was held on Jan. 14, 2004.

On April 28, 2004, the U.S. Supreme Court decided that the CAA Section 209 does, in fact, pre-empt local emissions standards. The Court recognized the impact of its decision by stating that "if one State or political subdivision may enact such rules, then so may any other; and the end result would undo Congress's carefully calibrated regulatory scheme." This was a clear victory for NAHB because any allowances for local standards or regulation would have been detrimental to our interests in any metropolitan area with air pollution.