CLAUSE 17. To exercise exclusive legislation in all cases whatsoever over such district (not exceeding ten miles square) as may, by cession of particular States, and the acceptance of Congress, become the seat of the government of the United States, and to exercise like authority over all places purchased by the consent of the Legislature of the State in which the same shall be, for the erection efforts, magazines, arsenals, dockyards, and other needful buildings;—And
CLAUSE 18. To make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this Constitution in the government of the United States, or in any department or officer thereof.
[Footnote: Section 9. Eight clauses now follow, enumerating the powers denied to Congress. What prohibition was made concerning the slave trade? Writ of habeas corpus? Bill of attainder? Ex-post-facto law? Direct tax? Exports from any state? Trade between the United States? Payments from the Treasury? Titles of nobility? United States office-holder receiving presents from a foreign power? (Notes.—The object of the first clause was to destroy the foreign slave trade or the importation of negroes from Africa for the purpose of enslaving them. In 1808, a law was passed prohibiting the trade, and in 1820 it was declared to be piracy. A writ of habeas corpus is a written order from a magistrate directing that a certain person shall be brought before him; its object is to guard against false imprisonment or trial in a prejudiced court. A bill of attainder is an English term, meaning an act which without trial inflicts death for treason: attainder of treason cannot in the United States work "corruption of blood" so as to prevent a person from transmitting lands to his descendants. An ex-post-facto law makes an act criminal or penal which was not so at the time it was committed. A United States office-holder, wishing to accept a present or distinction offered him by any foreign power, must ask permission of Congress before he can receive it.)]
SECTION IX.
CLAUSE 1. The migration or importation of such persons as any of the States now existing shall think proper to admit, shall not be prohibited by the Congress prior to the year one thousand eight hundred and eight, but a tax or duty may be imposed on such importation, not exceeding ten dollars for each person.
CLAUSE 2. The privilege of the writ of habeas corpus shall not be suspended, unless when in cases of rebellion or invasion the public safety may require it.
CLAUSE 3. No bill of attainder or ex-post-facto law shall be passed.
CLAUSE 4. No capitation or other direct tax shall be laid, unless in proportion to the census or enumeration hereinbefore directed to be taken.
CLAUSE 5. No tax or duty shall be laid on articles exported from any State.
CLAUSE 6. No preference shall be given by any regulation of commerce or revenue to the ports of one State over those of another; nor shall vessels bound to, or from, one State, be obliged to enter, clear, or pay duties in another.