Opinion of the Court
New York’s opposition? The answer is yes.
The interpretation of the Waterfront Commission Compact—an interstate compact approved by Congress—presents a federal question. See Cuyler v. Adams, 449 U. S. 433, 438 (1981). To resolve the dispute over whether each State may unilaterally withdraw, we “begin by examining the express terms of the Compact as the best indication of the intent of the parties.” Tarrant Regional Water Dist. v. Herrmann, 569 U. S. 614, 628 (2013).
Some interstate compacts expressly allow, prohibit, or limit unilateral withdrawal.[1] But this Compact does not address withdrawal. The Compact mentions neither “withdrawal” nor “termination” in any relevant context. The Compact provides for amendments, which require both States to agree. See Art. XVI(1), 67 Stat. 557. But unilateral withdrawal does not constitute an amendment to the Compact and thus does not implicate the amendment provision. The Compact also authorizes Congress to “alter, amend, or repeal” the Compact. See Art. XVI, §2, ibid. But Congress did not retain an exclusive right to terminate the Compact.
Because the Compact’s text does not address whether a State may unilaterally withdraw, we look to background principles of law that would have informed the parties’ understanding when they entered the Compact. This Court has long explained that interstate compacts “are construed as contracts under the principles of contract law.” Tarrant,
- ↑ See, e.g., Central Interstate Low-Level Radioactive Waste Compact, Art. VII(d), 99 Stat. 1870 (1986) (expressly allowing unilateral withdrawal); Snake River Compact, Art. XII, 64 Stat. 33 (1950) (expressly providing that the compact will remain in force unless terminated by both state legislatures and consented to by Congress); New York-New Jersey Port Authority Compact, Art. 21, 42 Stat. 179 (1921) (expressly allowing unilateral withdrawal within two years of the compact’s formation); Delaware River Basin Compact, Art. 1, §1.6(a), 75 Stat. 691 (1961) (expressly allowing unilateral termination only after 100 years).
