Article 1, Section 8, Clause 10
St. George Tucker, Blackstone's Commentaries 1:App. 268--691803
The definition of piracies, says the author of the Federalist, might perhaps, without inconvenience, be left to the law of nations: though a legislative definition of them is found in most municipal codes. A definition of felonies on the high seas is evidently requisite, being a term of loose signification, even in the common law of England. The true ground of granting these powers to congress seems to be, the immediate and near connection and relation which they have to the regulation of commerce with foreign nations, which must necessarily be transacted by the communication on the high seas; and the right of deciding upon questions of war and peace, where the law of nations, is the only guide. Under this head, of offences against the law of nations, the violation of the rights of ambassadors, as also of passports, and safe conducts is included. The act of 1 cong. 2 sess. c. 9, embraces the whole.
And here we may remark by the way, the very guarded manner in which congress are vested with authority to legislate upon the subject of crimes, and misdemeanors. They are not entrusted with a general power over these subjects, but a few offences are selected from the great mass of crimes with which society may be infested, upon which, only, congress are authorised to prescribe the punishment, or define the offence. All felonies and offences committed upon land, in all cases not expressly enumerated, being reserved to the states respectively. From whence this corollary seems to follow. That all crimes cognizable by the federal courts (except such as are committed in places, the exclusive jurisdiction of which has been ceded to the federal government) must be previously defined, (except treason,) and the punishment thereof previously declared, by the federal legislature.
The Founders' Constitution
Volume 3, Article 1, Section 8, Clause 10, Document 6
The University of Chicago Press
Tucker, St. George. Blackstone's Commentaries: With Notes of Reference to the Constitution and Laws of the Federal Government of the United States and of the Commonwealth of Virginia. 5 vols. Philadelphia, 1803. Reprint. South Hackensack, N.J.: Rothman Reprints, 1969.
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