Article I, Section 8, Clause 11:
[The Congress shall have Power . . .] To declare War, grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water; . . .
In Brown v. United States,1 Chief Justice Marshall dealt definitively with the legal position of enemy property during wartime. He held that the mere declaration of war by Congress does not effect a confiscation of enemy property situated within the territorial jurisdiction of the United States, but the right of Congress by further action to subject such property to confiscation was asserted in the most positive terms. As an exercise of the war power, such confiscation was held not subject to the restrictions of the Fifth and Sixth Amendments. Since such confiscation is unrelated to the personal guilt of the owner, it is immaterial whether the property belongs to an alien, a neutral, or even to a citizen. The whole doctrine of confiscation is built upon the foundation that it is an instrument of coercion, which, by depriving an enemy of property within his reach, whether within his territory or outside it, impairs his ability to resist the confiscating government and at the same furnishes to that government means for carrying on the war.2
Prizes of War
The power of Congress with respect to prizes is plenary; no one can have any interest in prizes captured except by permission of Congress.3 Nevertheless, since international law is a part of our law, the Court will administer it so long as it has not been modified by treaty or by legislative or executive action. Thus, during the Civil War, the Court found that the Confiscation Act of 1861, and the Supplementary Act of 1863, which, in authorizing the condemnation of vessels, made provision for the protection of interests of loyal citizens, merely created a municipal forfeiture and did not override or displace the law of prize. It decided, therefore, that when a vessel was liable to condemnation under either law, the government was at liberty to proceed under the most stringent rules of international law, with the result that the citizen would be deprived of the benefit of the protective provisions of the statute.4 Similarly, when Cuban ports were blockaded during the Spanish-American War, the Court held, over the vigorous dissent of three of its members, that the rule of international law exempting unarmed fishing vessels from capture was applicable in the absence of any treaty provision, or other public act of the government in relation to the subject.5