The whole question of the relation between state and federal citizenship came up for discussion and decision in the Dred Scott case7 decided in 1856. Two of the questions involved in this case were: Whether a State might make a negro one of its citizens; and, if so, whether such a one thereby necessarily became a citizen of the United States and as such entitled to the special privileges and immunities created by the Constitution, among which privileges was the right to bring a suit in a federal court under that clause of the Constitution which gives to the federal judiciary the power to hear and determine suits between "citizens of different States."

The plaintiff in this case was a negro of African descent, whose ancestors were of pure African blood, and who had been brought into this country and sold as slaves. The plea in abatement set up that, whether free or not, and whether by the laws of Missouri a citizen of that State or not, Scott was not, and could not by the action of a State be made a "citizen " in the strict sense of that word as used in Article III of the Constitution. In sustaining this plea, Chief Justice Taney in his opinion said: "The words 'people of the United States' and 'citizens' are synonymous terms, and mean the same thing. They both describe the political body who, according to our republican institutions, form the sovereignty, and who hold the power and conduct the government through their representatives. They are what we familiarly call the 'sovereign people,' and every citizen is one of this people and a constituent member of this sovereignty. The question before us is, whether the class of persons described in the plea in abatement compose a portion of this people, and are constituent members of this sovereignty. ... In discussing this question, we must not confound the rights of citizenship which a State may confer within its own limits, and the rights of citizenship as a member of the Union. It does not by any means follow, because he has all the rights and privileges of a citizen of a State, that he must be a citizen of the United States. He may have all the rights and privileges of the citizen of a State, and yet not be entitled to the rights and privileges of a citizen in any other State. For, previous to the adoption of the Constitution of the United States, every State had the undoubted right to confer on whomsoever it pleased the character of a citizen, and to endow him with all its rights. But this character, of course, was confined to the boundaries of the State, and gave him no rights or privileges in other States beyond those secured to him by the laws of nations and the comity of States. Nor have the several States surrendered the power of conferring these rights and privileges by adopting the Constitution of the United States. Each State may still confer them upon an alien, or anyone it thinks proper, or upon any class or description of persons; yet he would not be a citizen in the sense in which that word is used in the Constitution of the United States, nor entitled to sue as such in one of its courts, nor to the privileges and immunities of a citizen in the other States. The rights which he would acquire would be restricted to the State which gave them. The Constitution has conferred on Congress the right to establish an uniform rule of naturalization, and this right is evidently exclusive, and has always been held by this court to be so. Consequently no State, since the adoption of the Constitution, can, by naturalizing an alien, invest him with the rights and privileges secured to a citizen of a State under the Federal Government, although, so far as the State alone was concerned, he would undoubtedly be entitled to the rights of a citizen, and clothed with all the rights and immunities which the Constitution and laws of the State attached to that character."

7 Scott v. Sanford, 19 How. 393; 15 L. ed. 691.

There was no dissent on the part of any of the Justices of the Supreme Court from the doctrine declared by Taney that it did not lie within the power of the individual States to create federal citizens by admitting whomsoever they should see fit to their own citizenship. Justice Catron, however, argued that, under the pleadings, the plea in abatement, and, therefore, the question of citizenship, was not properly before the Supreme Court, and Justices McLean and Curtis in the particular ease at bar argued that Scott by fact of birth within the United States was a citizen of the United States, and, by domicile, was a citizen of the State of Missouri. In his dissenting opinion, Justice McLean argued that under the demurrer which was filed to the plea in abatement, Scott was to be considered a free man, and- that,-as such, whether or not he was of negro descent and had been a slave, he was a citizen of the United States and of the State in which he was domiciled. "Being born under our Constitution and laws," he said, "no naturalization is required, as one of foreign birth, to make him a citizen. The most general and appropriate definition of the term 'citizen' is a 'freeman.' Being a freeman, and having a domicile in a State different from that of the defendant, he is a citizen within the act of Congress, and the courts of the Union are open to him."