Pirate attacks in the waters off the Horn of Africa, including those on U.S.-flagged vessels, have brought continued U.S. and international attention to the long-standing problem of piracy in the region. The United States has been an active participant in piracy interdiction and prevention operations focusing on the Horn of Africa region. As part of operations, the U.S. military has detained individuals accused of acts of piracy against U.S.-flagged vessels. In some instances, these individuals have been brought to the United States for criminal prosecution in the federal courts. This report first examines the historical development of the offense of piracy, as defined by Congress and codified in the United States Code. The focus then turns to how contemporary international agreements define piracy. Finally, the report highlights developments in two trials involving charges of piracy in the federal district court in Norfolk, VA, United States v. Said and United States v. Hasan, specifically focusing on how the courts interpreted the definition of piracy under 18 U.S.C. § 1651. The U.S. Constitution, Art. I, § 8, cl. 10, provides that Congress has the power "To define and punish Piracies and Felonies committed on the high seas, and Offenses against the Law of Nations." Utilizing this authority, Congress has enacted legislation addressing piracy for over 200 years. For example, in 1790, Congress, in an act "for the punishment of certain crimes against the United States," addressed the offense of piracy, stating: That if any person or persons shall commit upon the high seas, or in any river, haven, basin or bay, out of the jurisdiction of any particular state, murder or robbery, or any other offence which if committed within the body of a county, would by the laws of the United States be punishable with death; or if any captain or mariner of any ship or other vessel, shall piratically and feloniously run away with such ship or vessel, or any goods or merchandise to the value of fifty dollars, or yield up such ship or vessel voluntarily to any pirate; or if any seaman shall lay violent hands upon his commander, thereby to hinder and prevent his fighting in defence of his ship or goods committed to his trust, or shall make a revolt in the ship; every such offender shall be deemed, taken and adjudged to be a pirate and felon, and being thereof convicted, shall suffer death; and the trial of crimes committed on the high seas, or in any place out of the jurisdiction of any particular state, shall be in the district where the offender is apprehended, or into which he may first be brought. In 1818, the U.S. Supreme Court, in U nited States v. Palmer , examined the offense of piracy as established under the Act of 1790. The case presented a series of questions, over which the lower court was divided, including what acts constituted the offense of piracy. The primary question was whether Congress intended for actions that would constitute robbery on land but committed on the high seas be considered piracy. It was argued that because the offense of robbery committed on land would not receive the death penalty, it would not be considered piracy when committed on the high seas. The argument relied on the inclusion of the qualifying statement "would by the laws of the United States be punishable with death" in the Act of 1790. After an extensive discussion of statutory interpretation, the Court held that the "meaning of the term robbery, as used in the statute, we think no doubt can be entertained. It must be understood in the sense in which it is recognized and defined at common law." Therefore, robbery committed on the high seas constituted the act of piracy, and as such, was punishable by death. A second question in Palmer addressed whether the crime of robbery committed by a non-U.S. citizen on the high seas and on a vessel belonging to the subjects of a foreign state could be considered piracy. The Court stated "[t]he constitution having conferred on congress the power of defining and punishing piracy, there can be no doubt of the right of the legislature to enact laws punishing pirates, although they may be foreigners, and may have committed no particular offence against the United States. The only question is, has the legislature enacted such a law?" Again examining the intent of Congress in enacting the legislation, the Court concluded that nations provide for offenses and punishments based on their own policies, but that no general words of a statute should be construed in a manner to make acts by foreigners against a foreign government unlawful under U.S. law. As such, the Court held that: The court is of the opinion that the crime of robbery, committed by a person on the high seas, on board of any ship or vessel belonging exclusively to subjects of a foreign state, on persons within a vessel belonging exclusively to subjects of a foreign state, is not a piracy within the true intent and meaning of the act for the punishment of certain crimes against the United States. Thus, after Palmer , piracy punishable in U.S. courts was the act of robbery, as recognized and defined by common law, committed on the high seas. However, the crime of robbery by a non-U.S. citizen committed on the high seas on board a vessel owned by subjects of a foreign state was not considered piracy under the Act of 1790, and as such, was not punishable in the courts of the United States. In 1819, arguably in response to Palmer , Congress passed an act "to protect the commerce of the United States, and punish the crime of piracy," which stated: That if any person or persons whatsoever, shall, on the high seas, commit the crime of piracy, as defined by the law of nations , and such offender or offenders, shall afterwards be brought into or found in the United States, every such offender or offenders shall, upon conviction thereof, before the circuit court of the United States for the district into which he or they may be brought, or in which he or they shall be found, be punished with death. The new language included a significant departure from the Act of 1790; the crime of piracy was defined not in specific terms, but rather "as defined by the law of nations." Additionally, Congress addressed the question of whether a non-U.S. citizen could be punished for an act of piracy on the high seas against a foreign owned ship, with the inclusion of statutory language stating "offenders shall be brought into or found in the United States" and if convicted of the alleged crime, "punished with death." Shortly after enactment of the new piracy statute, the Supreme Court had opportunity to address the constitutionality of the statute and definition in U nited States v. Smith . Smith, a member of a crew of a private armed vessel, was charged with piracy by the plunder and robbery of a Spanish vessel on the high seas. A jury found a special verdict that if "plunder and robbery" constituted piracy under the Act of 1819, then Smith was guilty of piracy; but if "plunder and robbery" did not constitute piracy, then Smith was not guilty. The circuit court, on the question of whether "plunder and robbery" constituted piracy by the law of nations and thus punishable under the Act of 1819, was divided and the question was certified to the Supreme Court. The question before the Supreme Court was whether the Act of 1819 was "a constitutional exercise of the authority delegated to Congress upon the subject of piracies." In an attempt to determine whether the Act of 1819 sufficiently defined the offense of piracy, as well as the jurisdictional reach of the United States, the court stated: So that, whether we advert to writers on the common law, or the maritime law, or the law of nations, we shall find that they universally treat of piracy as an offence against the law of nations, and that its true definition by that law is robbery upon the sea. And the general practice of all nations in punishing all persons, whether natives or foreigners, who have committed this offence against any persons whatsoever, with whom they are in amity, is a conclusive proof that the offence is supposed to depend, not upon the particular provisions of any municipal code, but upon the law of nations, both for its definition and punishment. Thus, the Supreme Court held that an act punishing "the crime of piracy, as defined by the law of nations" was within Congress's constitutional authority to "define and punish" since it adopted by reference the sufficiently precise definition of piracy under international law, that is, the act of "robbery upon the sea." In 1820, Congress reenacted parts of the 1819 Act, including the definition of piracy in Section 5, quoted above. The next statutory changes to the offense of piracy concerned the authorized punishment. The death penalty was replaced by "imprisonment at hard labor for life" in 1897, and then "imprisonment for life" in 1909 when the offense was stated as: Whoever, on the high seas, commits the crime of piracy as defined by the law of nations, and is afterwards brought into or found in the United States, shall be imprisoned for life. The 1909 definition remains unchanged and is currently codified at Title 18, Section 1651 of the United States Code. Several United Nations instruments address the problem of piracy, including the Convention on the High Seas, the Convention for the Suppression of Unlawful Acts Against the Safety of Maritime Navigation (SUA Convention), and the Convention on the Law of the Sea (UNCLOS). The United States is a signatory to the Convention on the High Seas and the SUA Convention, but not to UNCLOS.