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Peter Hsiao

Hsiao, Peter


Los Angeles, (213) 892-5731


University of Utah (B.S., 1982)
University of California, Berkeley, School of Law (J.D., 1985)

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Peter Hsiao is head of the Environment and Energy Group in Los Angeles and head of the Green Products and Chemicals team. Drawing upon his technical background as a chemical engineer, Mr. Hsiao has 30 years of experience in complex litigation and transactional work with a specialty as a lead trial attorney in environmental, natural resources, chemical toxic tort, and land use law.

Mr. Hsiao is recognized as one of the leading attorneys in environmental law. He is one of 16 lawyers named as a Distinguished Environmental Advocate by the American Bar Association, and is elected as a Fellow of the American College of Environmental Lawyers. He was appointed to the ABA's Standing Committee on Environmental Law and is the former Chair of the State Bar of California’s Environmental Law Section. Mr. Hsiao was named by the National Law Journal as a Trailblazer in Energy and Environmental Law. He is named by Best Lawyers in America as a leading lawyer in environmental law, and by Chambers and Partners as one of the best environmental lawyers. Legal 500 and PLC Global 3000 recommend him as one of the best environmental lawyers in the United States. The International Who’s Who of Business Lawyers named him as a leading cross-border environmental attorney. He is listed by Super Lawyers as one of the leading environmental lawyers in California. The Los Angeles Business Journal named him as one of the top environmental lawyers in Los Angeles. Martindale-Hubbell rates Mr. Hsiao as AV-Preeminent in Environmental Law and Litigation.

Mr. Hsiao served as a senior trial lawyer for the U.S. Department of Justice as an Assistant U.S. Attorney for the Central District of California. He was lead trial counsel representing the U.S. Environmental Protection Agency and other federal agencies in major environmental and chemical litigation. Mr. Hsiao obtained several multi-million dollar judgments, including the second-largest penalty for violation of the volatile organic compound limitations for consumer and industrial coatings, the largest recovery for cleanup of soil and groundwater pollution, and the then largest penalty for violation of EPA’s administrative order authority.

Mr. Hsiao received the U.S. Department of Justice’s Special Commendation Award, the U.S. Attorney’s Office Special Achievement Award, and the U.S. Fish and Wildlife Service Golden Eagle Award. He was selected to lecture at the Justice Department’s trial practice institute on trial practice in environmental cases. He has litigated cases in the U.S. Supreme Court, the federal courts of appeals, and the district and state courts. He also was appointed as a judge pro tem for the Los Angeles Municipal Court and has served as a mediator for environmental cases.

In private practice, Mr. Hsiao is an environmental trial attorney who advises Fortune 500 clients on a wide variety of complex environmental and land use matters. His cases include some of the largest environmental cases in California, including the cleanup of the San Francisco International Airport and the air pollution control measures for the Owens Dry Lake bed, the largest source of particulate air emissions in the United States. He represents clients in multi-party groundwater and soil contamination cases, hazardous waste management and disposal issues, and in Clean Air Act matters. He further advises both public and private clients on the state’s complex environmental assessment and land use planning requirements, and litigates cases under CEQA and NEPA.

Mr. Hsiao is the co-editor and co-author of the California Environmental and Natural Resources Law Handbook, a comprehensive treatise now in its 12th edition. He serves as a lecturer for the American Law Institute and the American Bar Association on expert witness testimony and litigation skills in chemical cases. He also has spoken and written widely on the subject of chemical regulation and litigation. Mr. Hsiao was nominated to membership in the American Chemical Society and is a former member and newsletter author for the American Institute of Chemical Engineers.

Mr. Hsiao is president of the board of directors of the Los Angeles County Bar Association Counsel for Justice, one of the nation’s oldest and largest providers of pro bono legal services. He is elected as a life fellow of the American Bar Foundation and is former chair of the State Bar of California Committee on Legal Services to the Poor. He is a recipient of the Wiley W. Manuel Award for pro bono legal services from the State Bar.

Mr. Hsiao is a magna cum laude graduate in chemical engineering from the University of Utah, where he received the Outstanding Student Award from the American Institute of Chemical Engineers. He obtained his J.D. in 1985 from the Boalt Hall School of Law, University of California at Berkeley, where he received the McBaine Advocacy Award.

Waste Management of Alameda County, Inc. v. East Bay Regional Park District
Represented the East Bay Regional Park District in a CERCLA case involving a former landfill that was being converted into a shoreline regional park along San Francisco Bay. Following trial, obtained a ruling allocating 95% of the response costs to Waste Management, the former owner and operator of the landfill, and only 5% to the Park District, as the site’s current owner.
First Fish and Game Approved Mitigation Plan
Represented IMC Corporation in defending criminal action regarding alleged illegal take of migratory birds from exposure to process ponds. Negotiated settlement and first-ever wildlife mitigation plan with California Department of Fish and Game under Fish and Game Code Section 3007. 
Hall Street Associates v. Mattel, Inc.
Successfully defended Mattel, Inc. before U.S. Supreme Court in case arising from contaminated property dispute in Beaverton, Oregon at site of former View Master facility. Although Mattel did not contaminate property, its landlord sought to hold it liable. Supreme Court heard procedural issue regarding whether expanded judicial review of arbitration decisions was available under Federal Arbitration Act. Court held in accordance with Mattel's assertion that no such expansion was available; case has been remanded for further proceedings.
Owens Lake and the Clean Air Act
Served as lead trial counsel to address the nation's largest source of particulate air emissions, the Owens Dry Lake Bed.  Obtained judgment after trial against Department of Water and Power, and settlement in administrative adjudication before California Air Resources Board.  The resulting settlement led to a new State Implementation Plan and shallow flooding of the lake bed. With a total value in excess of $100 million, it was the largest California environmental settlement in 2007. 
Cleanup of San Francisco International Airport
Served as lead trial counsel in federal court action City and County of San Francisco v. Atlantic Richfield, et al., (CV97-2965 N.D. Cal) to clean up historical contamination by numerous tenants at airport.  The resulting settlement and work commitment, which exceeded $140 million, was the largest environmental settlement in California in 2006. 
First Proposition 65 Judgment After Trial
Served as lead trial counsel for the nation's leading diesel engine manufacturers Cummins Engine Company, Inc., John Deere Construction Equipment Company, Detroit Diesel Corp., and Caterpillar, Inc., in the first defense judgment achieved after trial in a Proposition 65 action.  (Environmental World Watch v. Cummins Engine Company, LASC No. B128039.)

Peter Hsiao named NLJ 2015 Trailblazer in Energy & Environmental Law

Morrison & Foerster Advises on Landmark Environmental Protection Win

Peter Hsiao Elected to the American College of Environmental Lawyers

“Peter Hsiao impresses with his ‘extremely broad experience in all types of environmental issue,’ leveraging his experience as a chemical engineer when advising on disputes. His expert trial practice is particularly highlighted, with one client noting: ‘To hear him address a court is pure art.’”
Chambers USA 2015