The U.S. Supreme Court recently had the opportunity to overturn Auer deference, Kisor v. Wilkie, No. 18-15, (U.S. June 26, 2019). A 5-4 majority declined to do so, but not without emphasizing the limits of the doctrine. Auer deference refers to the doctrine that a court should generally defer to an agency’s interpretation of agency regulations when the regulations are determined to be ambiguous, see Auer v. Robbins, 519 U. S. 452 (1997). The doctrine also may be referred to as Seminole Rock deference, see Bowles v. Seminole Rock & Sand, 325 U.S. 410 (1945). This doctrine has been called into question because it essentially allows the regulatory body charged with writing the regulation the final say as to what the regulation means. Environmental lawyers, and anyone else involved in regulatory disputes, will likely want to keep the stated limits—whether new or old—front and center moving forward.

When an agency alleges an entity violated an environmental regulation, that entity is entitled to notice of the violation and a hearing. In the context of environmental decision-making, where the cost of compliance—or alleged noncompliance—can be high and may result in a bet-the-company type liability, it is particularly important for the entity to know what is expected of it. After exhausting administrative remedies and negotiations, entities take comfort in knowing a neutral judicial body will make a determination about the alleged noncompliance and that inquiry most often turns on an interpretation of the relevant regulation. If the language is clear on its face, then the language controls. The more difficult question arises when there is “genuine ambiguity.” Who has the final say in what the regulation means? The court or the agency? The Supreme Court has held deference to agency interpretation may still be appropriate in some instances, but there are limits to prevent a potential abuse of power.