Bill has been lead counsel for some of the most important and precedent-setting environmental law cases of his time, including regulatory challenges on greenhouse gases, air toxics regulation and cost/benefit analysis. Bill and his team litigate environmental cases before the US Court of Appeals and the US Supreme Court, manage proceedings before federal and state agencies and courts, and speak regularly before Congress. He also represents clients before State Attorneys General around the country. 

Beginning his legal career shortly after the enactment of the Clean Air Act, Bill has been on the forefront of every critical Clean Air regulatory proceeding facing the energy sector since then. He partners with Fortune 500 clients to promote sound regulation, to challenge regulatory overreach, and to build dynamic strategies for their future growth and success. Bill and his environmental team, represent trade associations, energy and manufacturing clients, and States and municipalities.

Bill is recognized for his groundbreaking work in environmental law related to litigation, regulation and counseling, and assists clients with matters relating to environmental regulation and litigation, climate change law, clean air regulation, environmental licensing and auditing, and waste management and clean water issues.