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Mason Morisset is one of the most experienced and successful litigators for Indian Law in the country. A veteran of over 50 years’ experience, he has successfully argued three cases to the United States Supreme Court: State v. Antoine -- treaty hunting rights, U.S. v. Washington -- Boldt Treaty fishing rights decision, and Arizona v. California -- Tribal water rights. He also argued scores of Federal Circuit Court and Federal District Court cases as well as many State court and Administrative court cases. Mason is the author of numerous articles on Indian law (see full list below) and a much in-demand speaker at seminars and symposia. He has presented lectures and papers at more than 150 events (complete list below). He has received many awards, including the 50 Year Award of Honor from the Washington State Bar Association.


Morisset, Schlosser, Jozwiak, & Somerville, Seattle, Washington                                                                     1969 – Present


Founding member of the firm and current principal attorney. Over 50 years of litigation experience and multiple Supreme Court victories. Focuses primarily on natural resource litigation, including water, fishing, and hunting rights of various tribes across the United States. 


University of California, Berkeley, California                                                                                                                                                 1968

             Juris Doctor Degree

            Member of Moot Court Honors, Editor for Boldt Hall Law School Newspaper


University of Washington, Seattle, Washington                                                                                                                                               1965

            Master of Arts in Political Science

            Majored in Constitutional Law, American Politics, and International Law


Lewis & Clark College, Portland, Oregon                                                                                                                                                        1963

            Bachelor of Science


Supreme Court

Arizona v. California, 530 U.S. 392 (June 19, 2000), United States Supreme Court No. 8 Original (Briefed and argued).  Issues: tribal water rights, allocation and use.  (Court reversed decision of Special Master which barred tribal water claim.  Remanded to allow tribe to claim additional land and water rights).

Washington v. Fishing Vessel Ass’n, 443 U.S. 658 (1979) (Argued and co‑counsel on the brief).  (Boldt Decision; Court held that Indian treaties reserved fifty percent of harvestable fish.)

Antoine v. Washington, 420 U.S. 194 (1975) (Briefed and argued).  (Court held that agreements with Indian tribes are entitled to favorable rules of construction.  Court required state authorities to recognize and abide by federal promise that tribe reserved hunting and fishing rights in contract of sale of reservation lands.)

Federal Circuit Courts of Appeals

Quechan Tribe of the Fort Yuma Indian Reservation v. United States, No. 11-16334, 599 Fed. Appx. 698, 2015 U.S. App. LEXIS 5258 (9th Cir. Ariz. 2015).  Duties of the Indian Health Service (IHS) and trust responsibility to tribes. 

Upper Skagit Indian Tribe v. Washington, No. 07-35061, (05-3) 590 F.3d 1020, 2010 U.S. App. LEXIS 137 (9th Cir. Wash. 2010).  Location of Treaty areas, boundaries of fishing zones. 


Upper Skagit Tribe v. Washington, No. 07-35061, (05-3) 576 F.3d 920, 2009 U.S. App. LEXIS 17511 (9th Cir. Wash. 2009).  Location of Treaty areas, boundaries of fishing zones. 

Tulalip Tribes v. Suquamish Indian Tribe, No. 13-35773, (05-4) 794 F.3d 1129, 2015 U.S. App. LEXIS 13015 (9th Cir. Wash. 2015).  Location of Treaty areas, boundaries of fishing zones. 

City of Tacoma v. Federal Energy Regulatory Comm’n (U.S. Court of Appeals for the District of Columbia Circuit, Consolidated Case Nos. 99‑1143, 99‑1192, 99‑1213, 99‑1299, 99‑1341, 00‑1001, 00‑1032, and 00‑1040).  Counsel (argued and briefed) for the Skokomish Indian Tribe, Intervenor. Issues:  Hydroelectric power licensing and water law issues, environmental matters, treaty rights.

Federal District Court

United States, et al. v. Washington, et al., (U.S. v. Washington Subproceeding No. 01‑01) (W.D. Wash., Cause No. 9213‑1‑01) (pending).  Issues:  Environmental and treaty rights, blockage of fish passage by state culverts.

United States, et al. v. Washington, et al., (U.S. v. Washington Subproceeding No. 00‑1) (W.D. Wash., Cause No. 9213‑00‑1) (pending).  Issues:  Intertribal allocation of fisheries resources.

Skokomish Indian Tribe, et al. v. United States, City of Tacoma, et al., U.S. District Court for the Western District of Washington, No. C99‑5606 (Pending).  Issues:  Damages to Indian tribe for breach of trust, destruction of fisheries resources, destruction of reservation lands, violation of water rights, etc.


Confederated Tribes and Bands of the Yakima Indian Nation v. Baldrige, U.S. District Court for the Western District of Washington, No. 80‑342 (pending) (co‑counsel in multi‑party complex litigation).  Issues:  Scope of treaty right to fish, effect of interstate fishing on treaty rights.


Red Lake Band of Chippewa, et al. v. C.I.R., U.S. District Court for the District of Minnesota, No. 4‑92 CIV 1147 (lead counsel).  Issues:  Treaty rights to harvest timber, income taxation, federal court procedural issues.


United States, et al. v. State of Washington, et al. (U.S. v. Washington Subproceeding No. 89‑3) (W.D. Wash., Cause No. 9213‑89‑3) (Dec. 20, 1994). (Co‑counsel in multi‑party complex litigation.)  Issues:  Treaty right to harvest shellfish and nonanadromous species, ownership and right of access to tidelands and seabeds for harvesting purposes, weight and scope of anthropological and historical evidence.

State Courts

Lummi, et al. v. Washington, et al., Washington Supreme Court (Oct. 28, 2010).

Quechan Indian Tribe v. Imperial County, et al., California Court of Appeal, Fourth Appellate District Cause No. D035409 (July 30, 2001). Counsel for Quechan Indian Tribe.  Issues:  Water rights, protection of cultural resources, land use.

Tulalip Tribes v. Barlow Bay Marina, et al., Washington State Court of Appeals No. 45693‑8‑I, 105 Wash. App. 1015 (Mar. 12, 2001).  Issues: Environmental protection, shellfish rights, pollution.

Postema v. PCHB, No. 67549‑0 (Wash. S.Ct. 2000), 142 Wash. 2d 68.  Issues:  Water rights, priority of streamflows for fisheries habitat.

Metropolitan Water Dist. v. Quechan Indian Tribe, Supreme Court of California Cause No. S089760 (Petition for review denied Sept. 13, 2000). Co‑counsel on complex multiparty litigation.  Issues:  Indian water rights, wheeling rates, water allocation.

Metropolitan Water Dist. v. Quechan Indian Tribe, California Court of Appeal, Second Appellate District Cause No. B119968 (May 30, 2000).  Co‑counsel on complex multiparty litigation.  Issues:  Indian water rights, wheeling rates, water allocation.


Indian Property Rights, Real Property Deskbook,  Author, published by the Washington State Bar Association (2009 & 2015)

“A Boldt From The Blue,” Chapter 6 in Turning Points in Washington’s Public Life, George Scott, Ph.D. (2011)

Tribes and Environmental Law:  Cooperation and Conflict,  Seattle Journal of Environment Law 29, Co-Author with Carly Summers (2009)

The Cushman Dam Case and Indian Treaty Rights, 27 Public Land & Resources Law Review, 23 (2009)

Clear Passage: The Culvert Case Decision as a Foundation for Habitat Protection and Preservation, Seattle Journal of Environmental Law and Policy (2009)


Fishing rights and U.S. v. Washington,  NWIFC Seminar Series (2016)

First Tribal Summit,  Lecturer on Tribal Water Policy and the Winter’s Doctrine ( November 2015)

Tribal Water Law,  Lecturer on Tribal Water Law (October 2015)

Energy Exports in the Northwest,  Seattle (August 2015)  

Water Law in Washington,  Law Seminars International (July 2015)

Tribal Water Law,  CLE International (October 2014)

Hydropower in the Northwest ,  Seminar Group (October 2014)

Tribal Sovereignty & Development,  Law Seminars International (September 2014)

Tribal Water Law in the Northwest,  Law Seminars International (July 2014)

Tribal Water Law in California,  Law Seminars International (March 2014)

Energy Exports in the Northwest,  Law Seminars International (October 2014)

Fishery Co-Management Conference,  Tulalip Tribes Board of Directors (October 2013)


Supreme Court of Washington, Bar Number 00273


US Federal Courts

United States Supreme Court

Eighth Circuit Court of Appeals

Ninth Circuit Court of Appeals

Tenth Circuit Court of Appeals

Court of Appeals for the Federal Circuit

United States Tax Court

United States Claims Court

United States Court of International Trade

U.S. District Courts

Western District of Washington

Eastern District of Washington

Eastern District of Michigan

Northern District of California

Western District of Michigan

Pro hac vice

District of Columbia

District of Alaska

District of North Dakota. Southwestern Division

District of South Dakota, Central Division

To view Mason's full resume, please visit our website from a tablet or computer!


Firm Director / Partner

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