Ernest J. Hahn

Ernie Hahn has a broad range of litigation experience, with a special emphasis on environmental litigation. Over the last fifteen years, Mr. Hahn has successfully represented clients in connection with the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA, aka “Superfund”), the Resource Conservation and Recovery Act (RCRA), the Clean Air Act (CAA), the Endangered Species Act (ESA), the Clean Water Act (CWA), the California Hazardous Substances Account Act (HSAA), the California Porter-Cologne Water Quality Control Act, and the California Safe Drinking Water and Toxic Enforcement Act of 1986 (Prop. 65). Mr. Hahn has represented clients at every level before state and federal trial and appellate courts in California, before numerous agency hearing boards, and is a licensed patent attorney admitted to practice before the U.S. Patent & Trademark Office. Mr. Hahn’s litigation experience covers cost recovery actions, toxic tort claims, insurance coverage and products liability claims, as well as a variety of tort, contract, intellectual property and property disputes. He has represented educational institutions in protecting student privacy concerns in the course of civil and criminal charges, and has served as counsel for several privately held businesses seeking to protect the confidentiality of their non-public information at trial, including First Amendment challenges.

Mr. Hahn’s practice also focuses on environmental regulatory compliance and strategic decision-making. He routinely counsels a variety of clients in their interactions with the U.S. Environmental Protection Agency, the California Department of Toxic Substances Control, the California State Water Resources Control Board, the California Air Resources Board, the Los Angeles Regional Water Quality Control Board and South Coast Air Quality Management District. Outside of California, he has counseled clients on various regulatory compliance issues in connection with State agencies in Georgia, Maine, Michigan, Nevada, New Jersey, Texas, and Washington. He also counsels clients on the regulatory and liability risks associated with climate change, both nationally and internationally, and previously served as counsel for the Republic of South Africa‚Äôs Department of Water Affairs and Forestry.

Mr. Hahn is uniquely qualified as an environmental counselor and litigator. Prior to attending law school, Mr. Hahn earned his Bachelor’s and Master’s degrees in Civil and Environmental Engineering, and was principally responsible for the design and implementation of the first surfactant-enhanced aquifer remediation project in the State of Michigan as part of his doctoral studies. Mr. Hahn’s deep technical expertise in environmental science, hydrogeology, and contaminant fate and transport allows him to seamlessly work hand-in-hand with environmental and technical in-house personnel and consulting experts in order to strategically evaluate and manage complex environmental concerns.


Bar Admission:



JD, cum laude, University of Michigan
Clarence Darrow Scholar
MSE, University of Michigan
BSE, cum laude, University of Michigan


U.S. District Court,
Central District of California