John A. Sheehan is Of Counsel at Cohen Milstein and a member of the firm’s Complex Tort Litigation practice group and Environmental Toxic Torts and Catastrophic Injury & Wrongful Death teams.

Mr. Sheehan has more than 30 years of experience in environment law and litigation, with a focus on state and federal water and wastewater quality issues. His distinguished career spans both the private and public sectors, providing clients with critical and inexhaustible insight into environmental law issues at the state and federal levels.  

Prior to joining Cohen Milstein, Mr. Sheehan was a Partner at a highly-regarded defense law firm, focused on the energy and natural resources sectors, where he represented drinking water and waste water trade associations and other industry clients in environmental litigation, regulatory enforcement actions, and transactional counseling related to key environmental statutes.

Mr. Sheehan’s litigation experience has also included defending private industry, state and municipal governments, and trade associations in environmental litigation in federal courts throughout the country, and in regulatory proceedings at the federal and state levels. In terms of plaintiffs’ experience, he notably represented the State of Florida in its lawsuit against BP, arising out of the Deepwater Horizon disaster.

Earlier in his career, Mr. Sheehan was a senior trial attorney at the U.S. Department of Justice in the Environment and Natural Resources Division. He was the lead trial attorney for the United States in major, precedent-setting litigation for the department. He was involved in several precedent setting cases under the Clean Water Act, the Clean Air Act, and Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). He served as the lead trial lawyer for the U.S. Environmental Protection Agency (EPA) in litigation brought by the tobacco industry related to secondhand tobacco smoke.

Mr. Sheehan was also previously a partner with a boutique environmental law firm that specialized in federal and state water quality issues where he counseled municipal and private industry clients on regulatory and compliance issues. He served as lead counsel in litigation for national association clients in federal courts and assisted communities in defense of enforcement actions by the U.S. Department of Justice for combined sewer overflow system violations.

Mr. Sheehan is a prolific writer and speaker on environmental litigation and regulatory challenges and related trends.

Mr. Sheehan served as an Executive Committee Member of the U.S. Chambers of Commerce’s Business Task Force on Water Policy.

Mr. Sheehan received a Special Achievement Award from the U.S. Department of Justice. He also received a Special Merit Award from the U.S. Environmental Protection Agency, Office of General Counsel. 

Mr. Sheehan received a B.A. in American Studies from Georgetown University in 1980, and a J.D. from Georgetown University Law Center in 1984, where he was a member of the American Criminal Law Review.