Daniel Mensher translates thorough preparation into courtroom success. Dan practices in Keller Rohrback’s nationally recognized Complex Litigation Group with a focus on complex environmental and consumer protection litigation. He enjoys collaborating with his colleagues and clients to identify problems and find creative, convincing solutions.
Dan has litigated important environmental and consumer cases across the country in federal and state court. He’s part of the Keller Rohrback team representing more than 50 counties, cities, tribes, and insurance pools in the fight to hold drug manufacturers and other entities accountable for the opioid crisis.
Before joining the firm, Dan was an environmental law professor at Lewis & Clark Law School in Portland, Oregon, where he also litigated cases involving toxic waste, water pollution, and natural resource management. He has sat on governmental advisory boards and helped to draft key environmental regulations in place today. Dan uses his passion and experience to protect our environment and the people and communities that rely on clean air, water, and products.
Bar and Court Admissions
2008, U.S. District Court for the District of Oregon
2008, U.S. Court of Appeals for the Ninth Circuit
2010, U.S. District Court for the District of Columbia Circuit
2011, U.S. District Court for the Western District of Wisconsin
2014, U.S. District Court for the Eastern District of Washington
2014, U.S. District Court for the Western District of Washington
Wesleyan University – B.A., 1998, History
University of Wisconsin – M.S., 2002, Geography
Lewis & Clark Law School – J.D., cum laude, 2007; Environmental Law Certificate; Cornelius Honors Society; Articles Editor, Environmental Law Review
Professional and Civic Involvement
Oregon State Bar Association, Member
Washington State Bar Association, Member
Toxic Free Future, Board Member
Northwest Environmental Defense Center, Board Member
Articles & Presentations
Speaker, Bridgeport Environmental Class Action Webinar, March 2016
Speaker, Harris Martin Porter Ranch Gas Leak Litigation Conference, “Testing of the Air Quality and Expert Witnesses for the Cases,” 19 January 2016
Daniel P. Mensher, With Friends Like These…: The Trouble With Auer Deference, 43 Envtl. Law Rev. 4 (2013).
Speaker, Oregon Water Law Conference, November 7, 2013 (Addressing issues in Water Quality Trading)
Speaker, Northwest Environmental Conference and Tradeshow, December 11, 2013 (The Precautionary Principle in Environmental Law)
Speaker, RainOps Conference, 2013, Spokane, WA, Longview, WA (Clean Water Act stormwater regulation)
Presenter, Oregon State Bar Environmental and Natural Resources Committee annual Continuing Legal Education Program, 2013 (salmon issues in Oregon and the Pacific Northwest)
Speaker, Oregon State Bar brown bag CLE debate with Oregon DOJ assistant attorney general about the Supreme Court case Decker v. NEDC, 2012
Daniel P. Mensher, Common Law On Ice: Using Federal Nuisance Law to Address Global Warming, 37 Envtl. Law Rev. 2 (2007).
Chris Rycewicz and Dan Mensher, Growing State Authority Under the Clean Water Act, 22 Nat. Resources & Env’t 2 (2007).