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Insular Cases


INSULAR CASES. Following its victory in the Spanish-American War (1898), the United States acquired Hawaii, Puerto Rico, Guam, and the Philippines. In the Insular Cases (1901–1922), the U.S. Supreme Court determined the constitutional and political status of the new territories. In De Lima v. Bidwell (1901), a customs dispute, a 5-to-4 majority ruled that Puerto Rico was not a "foreign country" for tariff purposes. In subsequent cases, the Court addressed the territories' relationship to the United States and whether "the Constitution follows the flag"; that is, whether and how constitutional provisions applied to these acquisitions. Many of the later cases were also decided by divided Courts, reflecting disagreement about the constitutional issues under-lying American expansionism.

The "incorporation" approach emerged as a central doctrine in the Court's decisions. This principle held that incorporated territories—those that Congress intended to become part of the United States and, eventually, states—were directly protected by the Constitution as written. However, it also held that only a limited set of rights applied to unincorporated possessions that Congress had not yet determined to make permanent parts of the Union. Thus, in Rassmussen v. United States (1905), the Court ruled that the Sixth Amendment required jury trials in Alaskan criminal cases because Alaska had been incorporated into the United States, while in Dorr v. United States (1904), it determined that jury trials were not required in the Philippine Islands, because they had not been incorporated. Puerto Rico, for which the doctrine of the Insular Cases would have the most enduring consequences, was unincorporated, according to Downes v. Bidwell (1901).Thus, it was treated as subject to the political authority of Congress, unrestrained by the full protections of the Constitution.


Kerr, James. The Insular Cases: The Role of the Judiciary in American Expansionism. Port Washington, N.Y.: Kennikat Press, 1982.

Ramos, Efren Rivera. "The Legal Construction of American Colonialism: The Insular Cases (1901–1922)." Revista Juridica Universidad de Puerto Rico 65 (1996): 225–328.

Torruella, Juan R. The Supreme Court and Puerto Rico: The Doctrine of Separate and Unequal. Río Piedras: University of Puerto Rico, 1985.

Gabriel J.Chin


See alsoGuam ; Hawaii ; Puerto Rico ; Territories of the United States .

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