The settled doctrine in the State courts of Louisiana is, that a French subject coming to the Orleans Territory, after the treaty of 1803 was made, and before Louisiana was admitted into the Union, and being an inhabitant at the time of the admission, became a citizen of the United States by that act; that he was one of the inhabitants contemplated by the third article of the treaty, which referred to all the inhabitants embraced within the new State on its admission.

That this is the true construction, I have no doubt.

If power existed to draw a line at thirty-six degrees thirty minutes north, so Congress had equal power to draw the line on the thirtieth degree—that is, due west from the city of New Orleans—and to declare that north of that line slavery should never exist. Suppose this had been done before 1812, when Louisiana came into the Union, and the question of infraction of the treaty had then been presented on the present assumption of power to prohibit slavery, who doubts what the decision of this court would have been on such an act of Congress; yet, the difference between the supposed line, and that on thirty-six degrees thirty minutes north, is only in the degree of grossness presented by the lower line.

The Missouri compromise line of 1820 was very aggressive; it declared that slavery was abolished forever throughout a country reaching from the Mississippi river to the Pacific ocean, stretching over thirty-two degrees of longitude, and twelve and a half degrees of latitude on its eastern side, sweeping over four-fifths, to say no more, of the original province of Louisiana.

That the United States Government stipulated in favor of the inhabitants to the extent here contended for, has not been seriously denied, as far as I know; but the argument is, that Congress had authority to repeal the third article of the treaty of 1803, in so far as it secured the right to hold slave property, in a portion of the ceded territory, leaving the right to exist in other parts. In other words, that Congress could repeal the third article entirely, at its pleasure. This I deny.

The compacts with North Carolina and Georgia were treaties also, and stood on the same footing of the Louisiana treaty; on the assumption of power to repeal the one, it must have extended to all, and Congress could have excluded the slaveholder of North Carolina from the enjoyment of his lands in the Territory now the State of Tennessee, where the citizens of the mother State were the principal proprietors.

And so in the case of Georgia. Her citizens could have been refused the right to emigrate to the Mississippi or Alabama Territory, unless they left their most valuable and cherished property behind them.

The Constitution was framed in reference to facts then existing or likely to arise: the instrument looked to no theories of Government. In the vigorous debates in the Convention, as reported by Mr. Madison and others, surrounding facts, and the condition and necessities of the country, gave rise to almost every provision; and among those facts, it was prominently true, that Congress dare not be intrusted with power to provide that, if North Carolina or Georgia ceded her western territory, the citizens of the State (in either case) could be prohibited, at the pleasure of Congress, from removing to their lands, then granted to a large extent, in the country likely to be ceded, unless they left their slaves behind. That such an attempt, in the face of a population fresh from the war of the Revolution, and then engaged in war with the great confederacy of Indians, extending from the mouth of the Ohio to the Gulf of Mexico, would end in open revolt, all intelligent men knew.

In view of these facts, let us inquire how the question stands by the terms of the Constitution, aside from the treaty? How it stood in public opinion when the Georgia cession was made, in 1802, is apparent from the fact that no guaranty was required by Georgia of the United States, for the protection of slave property. The Federal Constitution was relied on, to secure the rights of Georgia and her citizens during the Territorial condition of the country. She relied on the indisputable truths, that the States were by the Constitution made equals in political rights, and equals in the right to participate in the common property of all the States united, and held in trust for them. The Constitution having provided that "The citizens of each State shall be entitled to all privileges and immunities of citizens of the several States," the right to enjoy the territory as equals was reserved to the States, and to the citizens of the States, respectively. The cited clause is not that citizens of the United States shall have equal privileges in the Territories, but the citizen of each State shall come there in right of his State, and enjoy the common property. He secures his equality through the equality of his State, by virtue of that great fundamental condition of the Union—the equality of the States.

Congress cannot do indirectly what the Constitution prohibits directly. If the slaveholder is prohibited from going to the Territory with his slaves, who are parts of his family in name and in fact, it will follow that men owning lawful property in their own States, carrying with them the equality of their State to enjoy the common property, may be told, you cannot come here with your slaves, and he will be held out at the border. By this subterfuge, owners of slave property, to the amount of thousand of millions, might be almost as effectually excluded from removing into the Territory of Louisiana north of thirty-six degrees thirty minutes, as if the law declared that owners of slaves, as a class, should be excluded, even if their slaves were left behind.