United States v. State
The Supreme Court issued a fifth supplemental decree pinpointing the exact boundary line between California's offshore submerged lands and those belonging to the federal government, using precise geographic coordinates.
The order builds on a series of decrees stretching back to 1947 that have gradually drawn ever more precise lines dividing state and federal control over the seabed and its resources off California's coast.
How it got here: This is a continuation of an original Supreme Court boundary case between the United States and California dating back to 1947, now in its fifth supplemental decree.
The Case in Depth
What happened
Since 1947, the Supreme Court has resolved a long-running dispute between the United States and California over who owns the submerged lands, minerals, and natural resources beneath the Pacific Ocean off California's coast. Earlier decrees set the general framework and made partial boundary determinations; this decree continues that process by defining the boundary with detailed coordinates covering the mainland coast, the Farallon Islands, and the Channel Islands.
The question before the Court
Exactly where does the underwater boundary line run between California's coastal waters and federal waters off its coast?
Why it matters
This decree determines who controls valuable seabed resources—oil, gas, minerals, and fishing grounds—along California's coastline. By fixing the boundary with exact coordinates that can no longer shift, it gives the state and federal government, along with energy companies and regulators, a stable, unambiguous line for permitting and resource-management decisions.
What changes now
This is a final, binding decree fixing the boundary at specific coordinates rather than a temporary or emergency order. The boundary will no longer move with natural shoreline changes because the decree makes it fixed rather than ambulatory. The Court retains ongoing jurisdiction to handle any future disputes or clarifications needed to enforce or interpret this boundary determination.
How the Court got there
The legal reasoning, step by step
- The Court built on its original 1947 decree and the 1966 supplemental decree, which applied the Submerged Lands Act to divide ownership of offshore lands between the federal government and California.
- Three further supplemental decrees issued between 1977 and 1981 had already refined portions of this boundary, establishing a pattern of periodically adding precision to the line as surveying data improved.
- Applying the same statutory framework, the Court set out specific coordinate-based lines—covering the mainland coast, the Farallon Islands, and the Channel Islands—marking exactly where state-owned submerged lands end and federally-owned submerged lands begin.
- The Court specified that these coordinates use a particular mapping system (Universal Transverse Mercator, tied to a standard geodetic reference), ensuring the line can be located precisely and consistently on modern maps.
- Under the Submerged Lands Act, the Court fixed the boundary permanently at these coordinates so that it no longer shifts with natural changes in the coastline over time.