Agency Can Not Create An Affirmative Defense To Private Citizen Suits

Rafe Petersen is a Partner and Christine Walz is an Associate in our Washington D.C. office

In an opinion issued late last week, the D.C. Circuit held that the Environmental Protection Agency could not create an affirmative defense to private citizen suits under the Clean Air Act. 

In Natural Resources Defense Council v. EPA, several environmental organizations petitioned for review of a 2013 EPA Rule developing emissions standards for cement plants, in part because the rule created an affirmative defense for private civil suits in which plaintiffs sue sources of pollution and seek penalties for violations of emission standards.  The affirmative defense would have been available to defendants in cases where an "unavoidable" malfunction had resulted in impermissible levels of emissions.