United States v. Louisiana
Headline: Court fixes Alabama’s coastline by declaring Mississippi Sound state inland waters and approving a supplemental decree that sets Alabama’s offshore baseline, ending ambulatory coastline claims and resolving nearby Submerged Lands Act disputes.
Holding:
- Fixes Alabama’s offshore baseline and ends ambulatory coastline claims.
- Clarifies which offshore areas belong to Alabama under the Submerged Lands Act.
- Reduces future boundary disputes and provides clearer coastal management mapping.
Summary
Background
The dispute involved the State of Alabama, the State of Mississippi, and the United States over where Alabama’s coastline and offshore boundary should be drawn in Mississippi Sound. Earlier proceedings and a 1990 decree fixed much of the Mississippi and part of the Alabama baseline by coordinates, but a portion of Alabama’s coastline remained ambulatory (not fixed). The parties sought the Court’s help to resolve competing claims under the Submerged Lands Act (federal law that allocates nearby offshore areas to coastal states) and avoid future conflicts.
Reasoning
The central question was whether the Court should grant the parties’ joint motion to supplement the 1990 decree and fix Alabama’s remaining baseline. The Court granted the motion, adopted the Special Master’s recommendation that the whole of Mississippi Sound constitutes state inland waters for purposes of the 1960 decree, and approved a detailed baseline described by coordinates. The decree fixes that portion of Alabama’s coastline as of this order, stops it from remaining ambulatory, directs each party to bear its own costs, and leaves the Court’s continuing jurisdiction in place.
Real world impact
By fixing the baseline, the ruling determines which offshore areas count toward Alabama’s Submerged Lands Act grant and resolves the immediate dispute between Alabama and the United States. Coastal mapping, state control over nearby submerged lands, and resource rights will be clearer for Alabama and Mississippi. The Court’s retention of jurisdiction means further adjustments remain possible if needed.
Dissents or concurrances
No separate opinions were included in the decree; the Court issued the supplemental decree as described.
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